{"id":1274,"date":"2026-05-04T20:46:33","date_gmt":"2026-05-04T17:46:33","guid":{"rendered":"https:\/\/www.istatistik.gen.tr\/?p=1274"},"modified":"2026-05-04T20:52:04","modified_gmt":"2026-05-04T17:52:04","slug":"1274","status":"publish","type":"post","link":"https:\/\/www.istatistik.gen.tr\/?p=1274","title":{"rendered":"\u00d6rneklem Nedir? \u00d6rnekleme nas\u0131l yap\u0131l\u0131r?"},"content":{"rendered":"\n\n\n\n\n\n\u00d6rnekleme Y\u00f6ntemleri | istatistik.gen.tr<\/title>\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n<link href=\"https:\/\/fonts.googleapis.com\/css2?family=Source+Serif+4:ital,opsz,wght@0,8..60,300;0,8..60,400;0,8..60,600;0,8..60,700;1,8..60,400&family=JetBrains+Mono:wght@400;500&family=DM+Sans:wght@400;500;600&display=swap\" rel=\"stylesheet\">\n\n<style>\n\/* \u2500\u2500 Tema de\u011fi\u015fkenleri \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n:root {\n --ink: #1a1a2e;\n --ink-soft: #4a4a6a;\n --ink-ghost: #8888aa;\n --bg: #fafaf7;\n --bg-warm: #f5f3ee;\n --bg-panel: #eeeae0;\n --accent: #2255aa;\n --accent-mid: #3d6fcc;\n --accent-lt: #dce8ff;\n --warn: #b84400;\n --warn-lt: #fff0e6;\n --ok: #1a6b3a;\n --ok-lt: #e6f5ec;\n --gold: #8a6500;\n --gold-lt: #fff8dc;\n --purple: #5c3d8f;\n --purple-lt: #f0ebff;\n --serif: 'Source Serif 4', Georgia, serif;\n --sans: 'DM Sans', system-ui, sans-serif;\n --mono: 'JetBrains Mono', 'Fira Code', monospace;\n --radius: 6px;\n --shadow: 0 2px 12px rgba(34,85,170,.10);\n --shadow-lg: 0 8px 32px rgba(34,85,170,.14);\n}\n\n\/* \u2500\u2500 Reset & Base \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }\n\nhtml { scroll-behavior: smooth; font-size: 17px; }\n\nbody {\n font-family: var(--serif);\n background: var(--bg);\n color: var(--ink);\n line-height: 1.78;\n -webkit-font-smoothing: antialiased;\n}\n\n\/* \u2500\u2500 Header \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.site-header {\n background: var(--ink);\n padding: .75rem 2rem;\n display: flex;\n align-items: center;\n justify-content: space-between;\n position: sticky;\n top: 0;\n z-index: 100;\n box-shadow: 0 2px 8px rgba(0,0,0,.25);\n}\n.site-logo {\n font-family: var(--sans);\n font-weight: 600;\n font-size: .95rem;\n color: #fff;\n text-decoration: none;\n letter-spacing: .03em;\n}\n.site-logo span { color: #7ab0ff; }\n.header-tag {\n font-family: var(--sans);\n font-size: .75rem;\n color: #7ab0ff;\n border: 1px solid #7ab0ff55;\n border-radius: 20px;\n padding: .2rem .7rem;\n letter-spacing: .04em;\n}\n\n\/* \u2500\u2500 Hero \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.hero {\n background: linear-gradient(135deg, var(--ink) 0%, #1a2e5a 60%, #2255aa 100%);\n padding: 5rem 2rem 4rem;\n text-align: center;\n position: relative;\n overflow: hidden;\n}\n.hero::before {\n content: '';\n position: absolute;\n inset: 0;\n background: radial-gradient(ellipse at 30% 60%, rgba(100,160,255,.12) 0%, transparent 60%),\n radial-gradient(ellipse at 80% 20%, rgba(180,120,255,.08) 0%, transparent 50%);\n}\n.hero-eyebrow {\n font-family: var(--sans);\n font-size: .8rem;\n font-weight: 500;\n letter-spacing: .15em;\n text-transform: uppercase;\n color: #7ab0ff;\n margin-bottom: 1.2rem;\n position: relative;\n}\n.hero h1 {\n font-family: var(--serif);\n font-size: clamp(2rem, 5vw, 3.2rem);\n font-weight: 700;\n color: #fff;\n line-height: 1.2;\n max-width: 720px;\n margin: 0 auto 1rem;\n position: relative;\n}\n.hero-sub {\n font-family: var(--sans);\n font-size: 1.05rem;\n color: rgba(255,255,255,.65);\n max-width: 540px;\n margin: 0 auto 2rem;\n font-weight: 400;\n position: relative;\n}\n.hero-meta {\n display: flex;\n justify-content: center;\n gap: 1.5rem;\n flex-wrap: wrap;\n position: relative;\n}\n.hero-meta-item {\n font-family: var(--sans);\n font-size: .8rem;\n color: rgba(255,255,255,.5);\n display: flex;\n align-items: center;\n gap: .4rem;\n}\n.hero-meta-item svg { opacity: .6; }\n\n\/* \u2500\u2500 Layout \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.page-wrap {\n max-width: 820px;\n margin: 0 auto;\n padding: 3rem 1.5rem;\n}\n\n\/* \u2500\u2500 Inline TOC \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.toc-card {\n background: var(--bg-warm);\n border: 1px solid var(--bg-panel);\n border-radius: 10px;\n padding: 1.4rem 1.6rem;\n margin-bottom: 2.5rem;\n}\n.toc-title {\n font-family: var(--sans);\n font-size: .72rem;\n font-weight: 600;\n letter-spacing: .12em;\n text-transform: uppercase;\n color: var(--ink-ghost);\n margin-bottom: .8rem;\n}\n.toc-list {\n list-style: none;\n columns: 2;\n column-gap: 2rem;\n}\n.toc-list li { margin-bottom: .15rem; break-inside: avoid; }\n.toc-list a {\n font-family: var(--sans);\n font-size: .85rem;\n color: var(--accent);\n text-decoration: none;\n transition: opacity .15s;\n}\n.toc-list a:hover { opacity: .7; text-decoration: underline; }\n.toc-list .toc-sub { display: none; }\n\n\/* \u2500\u2500 Article \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.article { min-width: 0; }\n\n\/* \u2500\u2500 Tipografi \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.article h2 {\n font-family: var(--serif);\n font-size: 1.85rem;\n font-weight: 700;\n color: var(--ink);\n margin: 3rem 0 1rem;\n padding-bottom: .5rem;\n border-bottom: 2px solid var(--bg-panel);\n line-height: 1.25;\n}\n.article h2:first-child { margin-top: 0; }\n\n.article h3 {\n font-family: var(--serif);\n font-size: 1.3rem;\n font-weight: 600;\n color: var(--ink);\n margin: 2.2rem 0 .7rem;\n}\n.article h4 {\n font-family: var(--sans);\n font-size: .9rem;\n font-weight: 600;\n letter-spacing: .05em;\n text-transform: uppercase;\n color: var(--ink-soft);\n margin: 1.8rem 0 .6rem;\n}\n\n.article p {\n margin-bottom: 1.1rem;\n text-align: justify;\n hyphens: auto;\n}\n\n.article ul, .article ol {\n padding-left: 1.6rem;\n margin-bottom: 1.1rem;\n}\n.article li { margin-bottom: .4rem; }\n\nstrong { font-weight: 600; color: var(--ink); }\nem { font-style: italic; color: var(--ink-soft); }\n\n\/* \u2500\u2500 Section numaralar\u0131 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.section-num {\n display: inline-block;\n font-family: var(--sans);\n font-size: .7rem;\n font-weight: 600;\n letter-spacing: .08em;\n text-transform: uppercase;\n color: var(--accent);\n background: var(--accent-lt);\n border-radius: 3px;\n padding: .15rem .5rem;\n margin-bottom: .6rem;\n}\n\n\/* \u2500\u2500 Kutular \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.box {\n border-radius: var(--radius);\n padding: 1.3rem 1.5rem;\n margin: 1.5rem 0;\n border-left: 4px solid transparent;\n}\n.box-title {\n font-family: var(--sans);\n font-size: .82rem;\n font-weight: 600;\n letter-spacing: .06em;\n text-transform: uppercase;\n margin-bottom: .6rem;\n}\n.box p { margin-bottom: .5rem; text-align: left; }\n.box p:last-child { margin-bottom: 0; }\n\n.box-warn { background: var(--warn-lt); border-color: var(--warn); }\n.box-warn .box-title { color: var(--warn); }\n.box-ok { background: var(--ok-lt); border-color: var(--ok); }\n.box-ok .box-title { color: var(--ok); }\n.box-info { background: var(--accent-lt); border-color: var(--accent); }\n.box-info .box-title { color: var(--accent); }\n.box-gold { background: var(--gold-lt); border-color: var(--gold); }\n.box-gold .box-title { color: var(--gold); }\n.box-purple { background: var(--purple-lt); border-color: var(--purple); }\n.box-purple .box-title { color: var(--purple); }\n\n\/* Soru k\u00f6pr\u00fcs\u00fc *\/\n.bridge {\n background: var(--gold-lt);\n border: 1px solid #d4a900;\n border-radius: var(--radius);\n padding: 1rem 1.3rem;\n margin: 2rem 0;\n display: flex;\n align-items: flex-start;\n gap: .8rem;\n font-family: var(--sans);\n font-size: .95rem;\n font-weight: 500;\n color: var(--gold);\n line-height: 1.5;\n}\n.bridge-icon { font-size: 1.2rem; flex-shrink: 0; margin-top: .05rem; }\n\n\/* Senaryo kart\u0131 *\/\n.scenario-card {\n background: linear-gradient(135deg, #eef4ff 0%, #f5f0ff 100%);\n border: 1px solid #c8d8ff;\n border-radius: 10px;\n padding: 1.8rem;\n margin: 1.5rem 0;\n position: relative;\n overflow: hidden;\n}\n.scenario-card::before {\n content: '';\n position: absolute;\n top: -20px; right: -20px;\n width: 120px; height: 120px;\n background: radial-gradient(circle, rgba(100,150,255,.12), transparent 70%);\n border-radius: 50%;\n}\n.scenario-title {\n font-family: var(--sans);\n font-size: .78rem;\n font-weight: 600;\n letter-spacing: .1em;\n text-transform: uppercase;\n color: var(--accent);\n margin-bottom: .8rem;\n}\n.fakulte-grid {\n display: grid;\n grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));\n gap: .6rem;\n margin: 1rem 0;\n}\n.fakulte-card {\n background: rgba(255,255,255,.7);\n border: 1px solid #c8d8ff;\n border-radius: 6px;\n padding: .7rem 1rem;\n}\n.fakulte-name {\n font-family: var(--sans);\n font-size: .78rem;\n font-weight: 600;\n color: var(--accent);\n margin-bottom: .15rem;\n}\n.fakulte-n {\n font-family: var(--mono);\n font-size: .9rem;\n font-weight: 500;\n color: var(--ink);\n}\n\n\/* \u2500\u2500 Tablolar \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.table-wrap {\n overflow-x: auto;\n margin: 1.5rem 0;\n border-radius: var(--radius);\n box-shadow: var(--shadow);\n}\ntable {\n width: 100%;\n border-collapse: collapse;\n font-family: var(--sans);\n font-size: .85rem;\n background: #fff;\n}\nthead tr {\n background: var(--ink);\n color: #fff;\n}\nthead th {\n padding: .75rem 1rem;\n text-align: left;\n font-weight: 600;\n letter-spacing: .03em;\n font-size: .8rem;\n}\ntbody tr { border-bottom: 1px solid #eee; }\ntbody tr:nth-child(even) { background: var(--bg-warm); }\ntbody tr:hover { background: var(--accent-lt); }\ntbody td {\n padding: .65rem 1rem;\n color: var(--ink);\n line-height: 1.45;\n vertical-align: top;\n}\ntbody td:first-child { font-weight: 600; }\n\n\/* \u2500\u2500 Kod bloklar\u0131 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.code-wrap {\n margin: 1.5rem 0;\n border-radius: var(--radius);\n overflow: hidden;\n box-shadow: var(--shadow);\n border: 1px solid #2a2a3e;\n}\n.code-header {\n background: #1e1e2e;\n padding: .55rem 1rem;\n display: flex;\n align-items: center;\n justify-content: space-between;\n}\n.code-lang {\n font-family: var(--sans);\n font-size: .72rem;\n font-weight: 600;\n letter-spacing: .08em;\n text-transform: uppercase;\n color: #7eb8ff;\n}\n.code-copy {\n font-family: var(--sans);\n font-size: .72rem;\n color: #888;\n background: none;\n border: 1px solid #444;\n border-radius: 3px;\n padding: .15rem .5rem;\n cursor: pointer;\n transition: all .15s;\n}\n.code-copy:hover { color: #fff; border-color: #888; }\n.code-copy.copied { color: #7dde98; border-color: #7dde98; }\n\npre {\n background: #12121e;\n padding: 1.2rem 1.3rem;\n overflow-x: auto;\n margin: 0;\n font-family: var(--mono);\n font-size: .82rem;\n line-height: 1.7;\n}\n\n\/* S\u00f6zdizimi renkleri *\/\n.kw { color: #c792ea; } \/* keyword *\/\n.fn { color: #82aaff; } \/* function *\/\n.str { color: #c3e88d; } \/* string *\/\n.num { color: #f78c6c; } \/* number *\/\n.op { color: #89ddff; } \/* operator \/ pipe *\/\n.cm { color: #546e7a; font-style: italic; } \/* comment *\/\n.va { color: #eeffff; } \/* variable \/ default *\/\n.pn { color: #ffcb6b; } \/* punctuation \/ argument name *\/\n\n\/* \u2500\u2500 Kar\u015f\u0131la\u015ft\u0131rma kutusu \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.compare-grid {\n display: grid;\n grid-template-columns: 1fr 1fr;\n gap: 1rem;\n margin: 1.5rem 0;\n}\n.compare-card {\n border: 1px solid #ddd;\n border-radius: var(--radius);\n overflow: hidden;\n}\n.compare-card-head {\n padding: .6rem 1rem;\n font-family: var(--sans);\n font-size: .8rem;\n font-weight: 600;\n}\n.compare-card-body {\n padding: .8rem 1rem;\n font-size: .9rem;\n}\n.compare-pro { border-color: #c8e6c9; }\n.compare-pro .compare-card-head { background: #e8f5e9; color: var(--ok); }\n.compare-con { border-color: #ffccbc; }\n.compare-con .compare-card-head { background: #fbe9e7; color: var(--warn); }\n\n\/* \u2500\u2500 Progress \/ ad\u0131m sayac\u0131 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.method-badge {\n display: inline-flex;\n align-items: center;\n gap: .5rem;\n font-family: var(--sans);\n font-size: .78rem;\n font-weight: 600;\n letter-spacing: .05em;\n text-transform: uppercase;\n color: #fff;\n background: var(--accent);\n border-radius: 20px;\n padding: .25rem .9rem .25rem .65rem;\n margin-bottom: .8rem;\n}\n.method-badge-num {\n background: rgba(255,255,255,.25);\n border-radius: 50%;\n width: 1.3rem;\n height: 1.3rem;\n display: flex;\n align-items: center;\n justify-content: center;\n font-size: .7rem;\n}\n\n\/* \u2500\u2500 Footer \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n.site-footer {\n background: var(--ink);\n color: rgba(255,255,255,.5);\n text-align: center;\n padding: 2rem;\n font-family: var(--sans);\n font-size: .82rem;\n margin-top: 4rem;\n}\n.site-footer a { color: #7ab0ff; text-decoration: none; }\n\n\/* \u2500\u2500 Responsive \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n@media (max-width: 600px) {\n html { font-size: 15px; }\n .hero { padding: 3rem 1.2rem 2.5rem; }\n .article h2 { font-size: 1.5rem; }\n .fakulte-grid { grid-template-columns: 1fr 1fr; }\n .toc-list { columns: 1; }\n .compare-grid { grid-template-columns: 1fr; }\n .page-wrap { padding: 2rem 1.2rem; }\n}\n<\/style>\n<\/head>\n<body>\n\n<!-- \u2500\u2500 Header \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 -->\n<header class=\"site-header\">\n <a href=\"\/\" class=\"site-logo\">istatistik<span>.gen.tr<\/span><\/a>\n <span class=\"header-tag\">\u0130statistik Rehberi<\/span>\n<\/header>\n\n<!-- \u2500\u2500 Hero \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 -->\n<div class=\"hero\">\n <div class=\"hero-eyebrow\">Ara\u015ft\u0131rma Y\u00f6ntemleri<\/div>\n <h1>\u00d6rnekleme Y\u00f6ntemleri<\/h1>\n <p class=\"hero-sub\">\u00d6rneklem nedir, nas\u0131l se\u00e7ilir ve R ile nas\u0131l uygulan\u0131r?<\/p>\n <div class=\"hero-meta\">\n <span class=\"hero-meta-item\">\n <svg width=\"13\" height=\"13\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><circle cx=\"12\" cy=\"12\" r=\"10\"\/><polyline points=\"12 6 12 12 16 14\"\/><\/svg>\n ~15 dakika okuma\n <\/span>\n <span class=\"hero-meta-item\">\n <svg width=\"13\" height=\"13\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><polyline points=\"16 18 22 12 16 6\"\/><polyline points=\"8 6 2 12 8 18\"\/><\/svg>\n R kodu i\u00e7erir\n <\/span>\n <span class=\"hero-meta-item\">\n <svg width=\"13\" height=\"13\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M17 21v-2a4 4 0 0 0-4-4H5a4 4 0 0 0-4 4v2\"\/><circle cx=\"9\" cy=\"7\" r=\"4\"\/><path d=\"M23 21v-2a4 4 0 0 0-3-3.87\"\/><path d=\"M16 3.13a4 4 0 0 1 0 7.75\"\/><\/svg>\n Ba\u015flang\u0131\u00e7\u2013Orta d\u00fczey\n <\/span>\n <\/div>\n<\/div>\n\n<!-- \u2500\u2500 \u0130\u00e7erik + Sidebar \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 -->\n<div class=\"page-wrap\">\n\n <!-- \u2500\u2500 Makale \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 -->\n <article class=\"article\">\n\n <!-- Inline TOC -->\n <nav class=\"toc-card\">\n <div class=\"toc-title\">\u0130\u00e7indekiler<\/div>\n <ul class=\"toc-list\">\n <li><a href=\"#nedir\">1. \u00d6rnekleme Nedir?<\/a><\/li>\n <li><a href=\"#olasilikli\">2. Olas\u0131l\u0131kl\u0131 \u00d6rnekleme Y\u00f6ntemleri<\/a><\/li>\n <li><a href=\"#bro\">2.1 Basit Rastgele \u00d6rnekleme<\/a><\/li>\n <li><a href=\"#tabakali\">2.2 Tabakal\u0131 \u00d6rnekleme<\/a><\/li>\n <li><a href=\"#kume\">2.3 K\u00fcme \u00d6rneklemesi<\/a><\/li>\n <li><a href=\"#sistematik\">2.4 Sistematik \u00d6rnekleme<\/a><\/li>\n <li><a href=\"#arastirma-grubu\">3. Ara\u015ft\u0131rma Grubu Se\u00e7imi<\/a><\/li>\n <li><a href=\"#kolayda\">3.1 Kolayda Se\u00e7imi<\/a><\/li>\n <li><a href=\"#kartopu\">3.2 Kartopu Se\u00e7imi<\/a><\/li>\n <li><a href=\"#kota\">3.3 Kota Se\u00e7imi<\/a><\/li>\n <li><a href=\"#amacli\">3.4 Ama\u00e7l\u0131 Se\u00e7im<\/a><\/li>\n <li><a href=\"#sonuc\">4. Sonu\u00e7<\/a><\/li>\n <\/ul>\n <\/nav>\n\n <!-- 1. \u00d6rnekleme Nedir? -->\n <h2 id=\"nedir\">1. \u00d6rnekleme Nedir? Neden \u00d6nemlidir?<\/h2>\n\n <p>Diyelim ki T\u00fcrkiye’deki t\u00fcm \u00fcniversite \u00f6\u011frencilerinin haftal\u0131k ortalama ka\u00e7 saat ders \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 merak ediyorsunuz. Yakla\u015f\u0131k 8 milyon \u00f6\u011frencinin tamam\u0131na ula\u015fmaya \u00e7al\u0131\u015fmak \u2014 hepsine tek tek anket doldurmak, hepsinden veri toplamak \u2014 ne m\u00fcmk\u00fcnd\u00fcr ne de gereklidir. Bunun yerine bu b\u00fcy\u00fck gruptan, yani <strong>evrenden<\/strong>, daha k\u00fc\u00e7\u00fck bir alt k\u00fcme se\u00e7eriz ve bu alt k\u00fcmeyi inceleyerek evrenin tamam\u0131 hakk\u0131nda \u00e7\u0131kar\u0131mda bulunuruz. \u0130\u015fte bu alt k\u00fcmeye <strong>\u00f6rneklem<\/strong>, bu s\u00fcrece ise <strong>\u00f6rnekleme<\/strong> denir.<\/p>\n\n <p><strong>Evren (Pop\u00fclasyon):<\/strong> Ara\u015ft\u0131rmak istedi\u011fimiz t\u00fcm birey, nesne veya olaylar\u0131n b\u00fct\u00fcn\u00fcd\u00fcr.<\/p>\n <p><strong>\u00d6rneklem:<\/strong> Evrenden se\u00e7ilen ve evreni temsil etmesi beklenen alt k\u00fcmedir.<\/p>\n <p><strong>\u00d6rnekleme:<\/strong> Bu se\u00e7imi yaparken izledi\u011fimiz y\u00f6ntemin ad\u0131d\u0131r.<\/p>\n\n <div class=\"box box-warn\">\n <div class=\"box-title\">\u26a0\ufe0f Yayg\u0131n Yan\u0131lg\u0131: “Rastgele Birine Sormak = \u00d6rnekleme”<\/div>\n <p>Sokakta kar\u015f\u0131la\u015ft\u0131\u011f\u0131n\u0131z ki\u015filere anket doldurmak, al\u0131\u015fveri\u015f merkezinde duran herkese soru sormak ya da sosyal medyada bir link payla\u015f\u0131p cevap beklemek… Bunlar\u0131n hi\u00e7biri istatistiksel anlamda <strong>\u00f6rnekleme de\u011fildir.<\/strong><\/p>\n <p>Ger\u00e7ek \u00f6rneklemenin temeli \u015fudur: evreni olu\u015fturan t\u00fcm birimlerin bir listesine \u2014yani <strong>\u00f6rnekleme \u00e7er\u00e7evesine<\/strong>\u2014 sahip olunmas\u0131 ve se\u00e7imin bu listeden belirli bir olas\u0131l\u0131k mekanizmas\u0131yla yap\u0131lmas\u0131d\u0131r. Listeniz yoksa, olas\u0131l\u0131kl\u0131 \u00f6rnekleme yapamazs\u0131n\u0131z.<\/p>\n <\/div>\n\n <h3 id=\"cerceve\">\u00d6rnekleme \u00c7er\u00e7evesi: Listeniz Yoksa \u00d6rneklem de Yok<\/h3>\n\n <p>Bu liste nas\u0131l bir \u015fey olabilir? Ara\u015ft\u0131rman\u0131n kapsam\u0131na g\u00f6re de\u011fi\u015fir:<\/p>\n <ul>\n <li><strong>Bir \u00fcniversitenin \u00f6\u011frenci bilgi sistemi<\/strong> \u2192 o \u00fcniversitede kay\u0131tl\u0131 t\u00fcm \u00f6\u011frenciler<\/li>\n <li><strong>Bir hastanenin hasta kay\u0131tlar\u0131<\/strong> \u2192 belirli bir d\u00f6nemde ba\u015fvuran t\u00fcm hastalar<\/li>\n <li><strong>Bir belediyenin adres kay\u0131t sistemi<\/strong> \u2192 il\u00e7ede ikamet eden t\u00fcm haneler<\/li>\n <li><strong>Bir i\u015fletmenin \u0130K veritaban\u0131<\/strong> \u2192 \u015firketteki t\u00fcm \u00e7al\u0131\u015fanlar<\/li>\n <\/ul>\n\n <h3 id=\"senaryo\">Bu Yaz\u0131 Boyunca Kullanaca\u011f\u0131m\u0131z Senaryo<\/h3>\n\n <div class=\"scenario-card\">\n <div class=\"scenario-title\">\ud83d\udcca Senaryo: Hayali T\u00fcrkiye \u00dcniversitesi<\/div>\n <p>Hayali T\u00fcrkiye \u00dcniversitesi’nde <strong>10.000 \u00f6\u011frenci<\/strong> kay\u0131tl\u0131d\u0131r. \u00dcniversite d\u00f6rt fak\u00fclteden olu\u015fmaktad\u0131r:<\/p>\n <div class=\"fakulte-grid\">\n <div class=\"fakulte-card\">\n <div class=\"fakulte-name\">M\u00fchendislik<\/div>\n <div class=\"fakulte-n\">3.000 \u00f6\u011frenci<\/div>\n <\/div>\n <div class=\"fakulte-card\">\n <div class=\"fakulte-name\">\u0130ktisadi ve \u0130dari Bil.<\/div>\n <div class=\"fakulte-n\">2.500 \u00f6\u011frenci<\/div>\n <\/div>\n <div class=\"fakulte-card\">\n <div class=\"fakulte-name\">T\u0131p<\/div>\n <div class=\"fakulte-n\">1.500 \u00f6\u011frenci<\/div>\n <\/div>\n <div class=\"fakulte-card\">\n <div class=\"fakulte-name\">E\u011fitim<\/div>\n <div class=\"fakulte-n\">3.000 \u00f6\u011frenci<\/div>\n <\/div>\n <\/div>\n <p>Her fak\u00fclte 10’ar \u015fubeden olu\u015fmaktad\u0131r; toplam 40 \u015fube vard\u0131r. \u00dcniversitenin \u00f6\u011frenci bilgi sistemine eri\u015fimimiz oldu\u011funu \u2014 yani 10.000 ki\u015filik tam listeye sahip oldu\u011fumuzu \u2014 varsay\u0131yoruz.<\/p>\n <p><strong>Ara\u015ft\u0131rma sorusu:<\/strong> \u00d6\u011frenciler haftada ortalama ka\u00e7 saat ders \u00e7al\u0131\u015f\u0131yor?<\/p>\n <p>Bu senaryoyu d\u00f6rt farkl\u0131 olas\u0131l\u0131kl\u0131 \u00f6rnekleme y\u00f6ntemiyle ele alaca\u011f\u0131z. Her y\u00f6ntemde 200 ki\u015filik \u00f6rneklem \u00e7ekece\u011fiz ve sonu\u00e7lar\u0131 kar\u015f\u0131la\u015ft\u0131raca\u011f\u0131z.<\/p>\n <\/div>\n\n <h3 id=\"evren-r\">Evreni R’de Kural\u0131m<\/h3>\n <p>Ama \u00f6nce evreni R’de olu\u015ftural\u0131m. Bu kod yaz\u0131 boyunca de\u011fi\u015fmeyecek; her y\u00f6ntemde bu veri setini kullanaca\u011f\u0131z.<\/p>\n\n <div class=\"code-wrap\">\n <div class=\"code-header\">\n <span class=\"code-lang\">R<\/span>\n <button class=\"code-copy\" onclick=\"copyCode(this)\">Kopyala<\/button>\n <\/div>\n<pre><span class=\"cm\"># \u2500\u2500 K\u00fct\u00fcphaneler \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"kw\">library<\/span>(<span class=\"va\">dplyr<\/span>)\n\n<span class=\"cm\"># \u2500\u2500 Evrenin Olu\u015fturulmas\u0131 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"fn\">set.seed<\/span>(<span class=\"num\">42<\/span>) <span class=\"cm\"># Ayn\u0131 sonu\u00e7lar\u0131 tekrar \u00fcretmek i\u00e7in<\/span>\n\n<span class=\"va\">evren<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">data.frame<\/span>(\n <span class=\"pn\">ogrenci_id<\/span> <span class=\"op\">=<\/span> <span class=\"num\">1<\/span><span class=\"op\">:<\/span><span class=\"num\">10000<\/span>,\n <span class=\"pn\">fakulte<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">c<\/span>(\n <span class=\"fn\">rep<\/span>(<span class=\"str\">'Muhendislik'<\/span>, <span class=\"num\">3000<\/span>),\n <span class=\"fn\">rep<\/span>(<span class=\"str\">'IIBF'<\/span>, <span class=\"num\">2500<\/span>),\n <span class=\"fn\">rep<\/span>(<span class=\"str\">'Tip'<\/span>, <span class=\"num\">1500<\/span>),\n <span class=\"fn\">rep<\/span>(<span class=\"str\">'Egitim'<\/span>, <span class=\"num\">3000<\/span>)\n ),\n <span class=\"pn\">sube<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">c<\/span>(\n <span class=\"fn\">rep<\/span>(<span class=\"fn\">paste0<\/span>(<span class=\"str\">'M_Sube'<\/span>, <span class=\"num\">1<\/span><span class=\"op\">:<\/span><span class=\"num\">10<\/span>), <span class=\"pn\">each<\/span> <span class=\"op\">=<\/span> <span class=\"num\">300<\/span>), <span class=\"cm\"># M\u00fchendislik \u015fubeleri<\/span>\n <span class=\"fn\">rep<\/span>(<span class=\"fn\">paste0<\/span>(<span class=\"str\">'I_Sube'<\/span>, <span class=\"num\">1<\/span><span class=\"op\">:<\/span><span class=\"num\">10<\/span>), <span class=\"pn\">each<\/span> <span class=\"op\">=<\/span> <span class=\"num\">250<\/span>), <span class=\"cm\"># \u0130\u0130BF \u015fubeleri<\/span>\n <span class=\"fn\">rep<\/span>(<span class=\"fn\">paste0<\/span>(<span class=\"str\">'T_Sube'<\/span>, <span class=\"num\">1<\/span><span class=\"op\">:<\/span><span class=\"num\">10<\/span>), <span class=\"pn\">each<\/span> <span class=\"op\">=<\/span> <span class=\"num\">150<\/span>), <span class=\"cm\"># T\u0131p \u015fubeleri<\/span>\n <span class=\"fn\">rep<\/span>(<span class=\"fn\">paste0<\/span>(<span class=\"str\">'E_Sube'<\/span>, <span class=\"num\">1<\/span><span class=\"op\">:<\/span><span class=\"num\">10<\/span>), <span class=\"pn\">each<\/span> <span class=\"op\">=<\/span> <span class=\"num\">300<\/span>) <span class=\"cm\"># E\u011fitim \u015fubeleri<\/span>\n ),\n <span class=\"cm\"># Ger\u00e7ek\u00e7ilik i\u00e7in: T\u0131p \u00f6\u011frencileri daha \u00e7ok, E\u011fitim daha az \u00e7al\u0131\u015f\u0131yor<\/span>\n <span class=\"pn\">calisma_suresi<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">c<\/span>(\n <span class=\"fn\">rnorm<\/span>(<span class=\"num\">3000<\/span>, <span class=\"pn\">mean<\/span> <span class=\"op\">=<\/span> <span class=\"num\">28<\/span>, <span class=\"pn\">sd<\/span> <span class=\"op\">=<\/span> <span class=\"num\">6<\/span>), <span class=\"cm\"># M\u00fchendislik<\/span>\n <span class=\"fn\">rnorm<\/span>(<span class=\"num\">2500<\/span>, <span class=\"pn\">mean<\/span> <span class=\"op\">=<\/span> <span class=\"num\">22<\/span>, <span class=\"pn\">sd<\/span> <span class=\"op\">=<\/span> <span class=\"num\">5<\/span>), <span class=\"cm\"># \u0130\u0130BF<\/span>\n <span class=\"fn\">rnorm<\/span>(<span class=\"num\">1500<\/span>, <span class=\"pn\">mean<\/span> <span class=\"op\">=<\/span> <span class=\"num\">35<\/span>, <span class=\"pn\">sd<\/span> <span class=\"op\">=<\/span> <span class=\"num\">8<\/span>), <span class=\"cm\"># T\u0131p<\/span>\n <span class=\"fn\">rnorm<\/span>(<span class=\"num\">3000<\/span>, <span class=\"pn\">mean<\/span> <span class=\"op\">=<\/span> <span class=\"num\">20<\/span>, <span class=\"pn\">sd<\/span> <span class=\"op\">=<\/span> <span class=\"num\">5<\/span>) <span class=\"cm\"># E\u011fitim<\/span>\n )\n)\n\n<span class=\"cm\"># Ger\u00e7ek evren ortalamas\u0131 \u2014 \u00f6rnekleme y\u00f6ntemlerimiz bunu tahmin etmeye \u00e7al\u0131\u015facak<\/span>\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Ger\u00e7ek evren ortalamas\u0131:'<\/span>, <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">evren<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>), <span class=\"str\">'saat\/hafta\\n'<\/span>)\n<span class=\"cm\"># \u00c7\u0131kt\u0131: Ger\u00e7ek evren ortalamas\u0131: 26.33 saat\/hafta<\/span><\/pre>\n <\/div>\n\n <!-- 2. Olas\u0131l\u0131kl\u0131 -->\n <h2 id=\"olasilikli\">2. Olas\u0131l\u0131\u011fa Dayal\u0131 \u00d6rnekleme Y\u00f6ntemleri<\/h2>\n\n <p>Olas\u0131l\u0131\u011fa dayal\u0131 \u00f6rnekleme y\u00f6ntemlerinde evreni olu\u015fturan her birimin se\u00e7ilme olas\u0131l\u0131\u011f\u0131 s\u0131f\u0131rdan b\u00fcy\u00fckt\u00fcr ve bu olas\u0131l\u0131k \u00f6nceden hesaplanabilir. Bu \u00f6zellik, \u00f6rneklemden elde edilen sonu\u00e7lar\u0131n evrene genellenmesini olanakl\u0131 k\u0131lar.<\/p>\n\n <!-- 2.1 Basit Rastgele -->\n <h3 id=\"bro\">\n <div class=\"method-badge\"><span class=\"method-badge-num\">1<\/span>Basit Rastgele \u00d6rnekleme<\/div>\n <\/h3>\n\n <p>En saf haliyle \u00f6rnekleme budur: listedeki 10.000 \u00f6\u011frenciden 200’\u00fcn\u00fc tamamen \u015fansa b\u0131rakarak se\u00e7eriz. Her \u00f6\u011frencinin se\u00e7ilme olas\u0131l\u0131\u011f\u0131 birbirine e\u015fittir: <strong>200 \/ 10.000 = 0,02<\/strong>. Bir piyango gibi d\u00fc\u015f\u00fcnebilirsiniz; herkesin biletinin kazanma \u015fans\u0131 ayn\u0131d\u0131r.<\/p>\n\n <p><strong>Kula\u011fa m\u00fckemmel geliyor, de\u011fil mi? Ama bir d\u00fc\u015f\u00fcnelim.<\/strong><\/p>\n\n <p>Evrenimizde d\u00f6rt fak\u00fclte var ve bunlar\u0131n b\u00fcy\u00fckl\u00fckleri birbirinden olduk\u00e7a farkl\u0131. <strong>T\u0131p fak\u00fcltesinde yaln\u0131zca 1.500 \u00f6\u011frenci<\/strong> bulunurken <strong>M\u00fchendislik ve E\u011fitim’de 3.000’er \u00f6\u011frenci<\/strong> var. Tamamen \u015fansa b\u0131rak\u0131lan bir se\u00e7imde 200 ki\u015filik \u00f6rnekleme b\u00fcy\u00fck ihtimalle kalabal\u0131k fak\u00fcltelerden \u00e7ok daha fazla \u00f6\u011frenci girecek, T\u0131p fak\u00fcltesi ise \u00f6rneklemde olduk\u00e7a az temsil edilecektir.<\/p>\n\n <p>Bu bir sorun mudur? Ara\u015ft\u0131rma sorunuza ba\u011fl\u0131d\u0131r. E\u011fer <strong>yaln\u0131zca genel ortalamay\u0131<\/strong> tahmin etmek istiyorsan\u0131z, bu dengesizlik b\u00fcy\u00fck bir sorun olu\u015fturmayabilir. Ancak <em>“T\u0131p \u00f6\u011frencileri di\u011ferlerinden ne kadar farkl\u0131?”<\/em> ya da <em>“Fak\u00fclteler aras\u0131ndaki fark nedir?”<\/em> gibi sorular\u0131n\u0131z varsa, T\u0131p fak\u00fcltesinden \u00f6rnekleme yeterince \u00f6\u011frenci girmedi\u011fi i\u00e7in g\u00fcvenilir bir kar\u015f\u0131la\u015ft\u0131rma yapamayabilirsiniz.<\/p>\n\n <p><strong>Hemen g\u00f6relim.<\/strong><\/p>\n\n <div class=\"code-wrap\">\n <div class=\"code-header\">\n <span class=\"code-lang\">R<\/span>\n <button class=\"code-copy\" onclick=\"copyCode(this)\">Kopyala<\/button>\n <\/div>\n<pre><span class=\"cm\"># \u2500\u2500 Basit Rastgele \u00d6rnekleme \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"fn\">set.seed<\/span>(<span class=\"num\">42<\/span>)\n<span class=\"va\">n<\/span> <span class=\"op\"><-<\/span> <span class=\"num\">200<\/span>\n\n<span class=\"va\">bro<\/span> <span class=\"op\"><-<\/span> <span class=\"va\">evren<\/span> <span class=\"op\">%>%<\/span>\n <span class=\"fn\">slice_sample<\/span>(<span class=\"pn\">n<\/span> <span class=\"op\">=<\/span> <span class=\"va\">n<\/span>)\n\n<span class=\"cm\"># Fak\u00fclte da\u011f\u0131l\u0131m\u0131<\/span>\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Fak\u00fclte da\u011f\u0131l\u0131m\u0131 (basit rastgele):\\n'<\/span>)\n<span class=\"fn\">print<\/span>(<span class=\"fn\">table<\/span>(<span class=\"va\">bro<\/span><span class=\"op\">$<\/span><span class=\"va\">fakulte<\/span>))\n\n<span class=\"cm\"># \u00c7\u0131kt\u0131 (yakla\u015f\u0131k):<\/span>\n<span class=\"cm\"># Egitim IIBF Muhendislik Tip<\/span>\n<span class=\"cm\"># 60 49 59 32<\/span>\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\\nOrtalama \u00e7al\u0131\u015fma s\u00fcresi:'<\/span>, <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">bro<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>), <span class=\"str\">'saat\/hafta\\n'<\/span>)\n<span class=\"cm\"># Kar\u015f\u0131la\u015ft\u0131rma: Ger\u00e7ek evren ortalamas\u0131 26.33 saat\/hafta<\/span><\/pre>\n <\/div>\n\n <p>\u00c7\u0131kt\u0131ya bak\u0131n: 200 ki\u015filik \u00f6rneklemimizde <strong>T\u0131p’tan yaln\u0131zca 32 ki\u015fi<\/strong> var. Bu sefer \u015fans nispeten iyi davrand\u0131. Ama \u015fans her zaman bu kadar iyi olmayabilir. K\u00fc\u00e7\u00fck gruplar, basit rastgele \u00f6rneklemede kolayl\u0131kla yetersiz temsil edilebilir.<\/p>\n\n <p>Peki basit rastgele \u00f6rnekleme hi\u00e7 mi i\u015fe yaramaz? Aksine, <strong>evreni olu\u015fturan bireyler birbirinden fazla farkl\u0131la\u015fm\u0131yorsa<\/strong> m\u00fckemmel bir y\u00f6ntemdir. Birka\u00e7 ger\u00e7ek hayat \u00f6rne\u011fi:<\/p>\n <ul>\n <li><strong>Kalite kontrol:<\/strong> Bir fabrikadan \u00e7\u0131kan binlerce vidan\u0131n kalitesini denetliyorsunuz. Vidalar aras\u0131nda “fak\u00fclte” gibi yap\u0131sal bir farkl\u0131l\u0131k yok; herhangi 200 vida, t\u00fcm \u00fcretimi temsil edebilir.<\/li>\n <li><strong>Homojen \u00e7al\u0131\u015fan anketi:<\/strong> Ayn\u0131 fabrikada benzer i\u015fleri yapan \u00e7al\u0131\u015fanlar\u0131n i\u015f tatminini \u00f6l\u00e7\u00fcyorsunuz. Gruplar aras\u0131nda b\u00fcy\u00fck yap\u0131sal farklar yoksa basit rastgele yeterlidir.<\/li>\n <li><strong>Finansal denetim:<\/strong> Binlerce fatura aras\u0131ndan rastgele se\u00e7im yaparak hata oran\u0131n\u0131 tahmin ediyorsunuz.<\/li>\n <\/ul>\n\n <div class=\"bridge\">\n <span class=\"bridge-icon\">\ud83e\udd14<\/span>\n Peki ya evren i\u00e7inde birbiriyle yap\u0131sal olarak farkl\u0131la\u015fan gruplar varsa ve bu gruplar\u0131n her birinin ayr\u0131 ayr\u0131 temsil edilmesini garantilemek istiyorsak?\n <\/div>\n\n <!-- 2.2 Tabakal\u0131 -->\n <h3 id=\"tabakali\">\n <div class=\"method-badge\"><span class=\"method-badge-num\">2<\/span>Tabakal\u0131 \u00d6rnekleme<\/div>\n <\/h3>\n\n <p>Tam da bu sorunun cevab\u0131 <strong>tabakal\u0131 \u00f6rneklemedir.<\/strong> Evren \u00f6nce anlaml\u0131 alt gruplara \u2014 <strong>tabakalara<\/strong> \u2014 b\u00f6l\u00fcn\u00fcr; ard\u0131ndan her tabakadan ayr\u0131 ayr\u0131 \u00f6rneklem \u00e7ekilir. B\u00f6ylece her grubun \u00f6rneklemde temsili garanti alt\u0131na al\u0131nm\u0131\u015f olur.<\/p>\n\n <p>Bizim senaryomuzda fak\u00fclteler do\u011fal tabakalar\u0131 olu\u015fturuyor. Orant\u0131l\u0131 tabakalamada her fak\u00fclteden, o fak\u00fcltenin evrendeki a\u011f\u0131rl\u0131\u011f\u0131yla orant\u0131l\u0131 say\u0131da \u00f6\u011frenci al\u0131yoruz:<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Fak\u00fclte<\/th>\n <th>Evrendeki \u00d6\u011frenci Say\u0131s\u0131<\/th>\n <th>Evrendeki Oran\u0131<\/th>\n <th>200 Ki\u015filik \u00d6rnekleme D\u00fc\u015fen Pay<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td>M\u00fchendislik<\/td><td>3.000<\/td><td>%30<\/td><td><strong>60 ki\u015fi<\/strong><\/td><\/tr>\n <tr><td>\u0130ktisadi ve \u0130dari Bil.<\/td><td>2.500<\/td><td>%25<\/td><td><strong>50 ki\u015fi<\/strong><\/td><\/tr>\n <tr><td>T\u0131p<\/td><td>1.500<\/td><td>%15<\/td><td><strong>30 ki\u015fi<\/strong><\/td><\/tr>\n <tr><td>E\u011fitim<\/td><td>3.000<\/td><td>%30<\/td><td><strong>60 ki\u015fi<\/strong><\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>T\u0131p fak\u00fcltesi art\u0131k \u015fansa b\u0131rak\u0131lm\u0131yor: <strong>tam olarak 30 ki\u015fi<\/strong> bu fak\u00fclteden gelecek. K\u00fc\u00e7\u00fck gruplar\u0131n temsili garantilenmi\u015f oluyor. \u00dcstelik fak\u00fclteye g\u00f6re farkl\u0131l\u0131klar\u0131 analiz etmek istedi\u011fimizde elimizde her gruptan yeterli veri olacak.<\/p>\n\n <p>Tabakal\u0131 \u00f6rneklemenin bir di\u011fer g\u00fczel yan\u0131 <strong>istatistiksel hassasiyettir.<\/strong> Basit rastgele \u00f6rneklemede t\u00fcm bireyleri tek bir havuza at\u0131p \u015fansa b\u0131rak\u0131r\u0131z; tabakalamada ise homojen gruplar i\u00e7inden se\u00e7im yap\u0131ld\u0131\u011f\u0131 i\u00e7in tahminlerimiz daha isabetli olur. Daha az \u00f6rneklemle ayn\u0131 g\u00fcveni elde edebiliriz \u2014 ya da ayn\u0131 \u00f6rneklemle daha dar g\u00fcven aral\u0131klar\u0131 elde ederiz.<\/p>\n\n <p><strong>Hemen deneyelim ve basit rastgele ile kar\u015f\u0131la\u015ft\u0131ral\u0131m:<\/strong><\/p>\n\n <div class=\"code-wrap\">\n <div class=\"code-header\">\n <span class=\"code-lang\">R<\/span>\n <button class=\"code-copy\" onclick=\"copyCode(this)\">Kopyala<\/button>\n <\/div>\n<pre><span class=\"cm\"># \u2500\u2500 Tabakal\u0131 \u00d6rnekleme (Orant\u0131l\u0131) \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"fn\">set.seed<\/span>(<span class=\"num\">42<\/span>)\n<span class=\"va\">n_toplam<\/span> <span class=\"op\"><-<\/span> <span class=\"num\">200<\/span>\n\n<span class=\"va\">tabakali<\/span> <span class=\"op\"><-<\/span> <span class=\"va\">evren<\/span> <span class=\"op\">%>%<\/span>\n <span class=\"fn\">group_by<\/span>(<span class=\"va\">fakulte<\/span>) <span class=\"op\">%>%<\/span>\n <span class=\"cm\"># Her fak\u00fclteden, evrendeki oran\u0131yla orant\u0131l\u0131 say\u0131da ki\u015fi se\u00e7<\/span>\n <span class=\"fn\">slice_sample<\/span>(<span class=\"pn\">prop<\/span> <span class=\"op\">=<\/span> <span class=\"va\">n_toplam<\/span> <span class=\"op\">\/<\/span> <span class=\"fn\">nrow<\/span>(<span class=\"va\">evren<\/span>)) <span class=\"op\">%>%<\/span>\n <span class=\"fn\">ungroup<\/span>()\n\n<span class=\"cm\"># Fak\u00fclte da\u011f\u0131l\u0131m\u0131<\/span>\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Fak\u00fclte da\u011f\u0131l\u0131m\u0131 (tabakal\u0131):\\n'<\/span>)\n<span class=\"fn\">print<\/span>(<span class=\"fn\">table<\/span>(<span class=\"va\">tabakali<\/span><span class=\"op\">$<\/span><span class=\"va\">fakulte<\/span>))\n\n<span class=\"cm\"># \u00c7\u0131kt\u0131:<\/span>\n<span class=\"cm\"># Egitim IIBF Muhendislik Tip<\/span>\n<span class=\"cm\"># 60 50 60 30 \u2190 Her fak\u00fclte tam oran\u0131nda temsil ediliyor<\/span>\n\n<span class=\"cm\"># Fak\u00fclteye g\u00f6re ortalama \u00e7al\u0131\u015fma s\u00fcreleri<\/span>\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\\nFak\u00fclteye g\u00f6re ortalamalar:\\n'<\/span>)\n<span class=\"va\">tabakali<\/span> <span class=\"op\">%>%<\/span>\n <span class=\"fn\">group_by<\/span>(<span class=\"va\">fakulte<\/span>) <span class=\"op\">%>%<\/span>\n <span class=\"fn\">summarise<\/span>(\n <span class=\"pn\">n<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">n<\/span>(),\n <span class=\"pn\">ort_calisma<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>),\n <span class=\"pn\">std_sapma<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">round<\/span>(<span class=\"fn\">sd<\/span>(<span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>)\n ) <span class=\"op\">%>%<\/span>\n <span class=\"fn\">print<\/span>()\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\\nGenel ortalama:'<\/span>, <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">tabakali<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>), <span class=\"str\">'saat\/hafta\\n'<\/span>)<\/pre>\n <\/div>\n\n <p>Fak\u00fclteye g\u00f6re ortalamalara bak\u0131ld\u0131\u011f\u0131nda T\u0131p \u00f6\u011frencileri haftada yakla\u015f\u0131k 35 saat \u00e7al\u0131\u015f\u0131rken E\u011fitim \u00f6\u011frencileri yakla\u015f\u0131k 20 saat \u00e7al\u0131\u015f\u0131yor. Basit rastgele \u00f6rneklemede de benzer bir genel ortalama \u00e7\u0131kabilir; ancak T\u0131p’tan az ki\u015fi geldiyse bu farkl\u0131l\u0131\u011f\u0131 g\u00fcvenilir bi\u00e7imde saptayamay\u0131z. <strong>Tabakal\u0131 \u00f6rnekleme, bu fark\u0131 g\u00f6r\u00fcn\u00fcr k\u0131l\u0131yor.<\/strong><\/p>\n\n <div class=\"box box-info\">\n <div class=\"box-title\">\u2139\ufe0f Tabakal\u0131 \u00d6rneklemenin \u00d6n Ko\u015fulu<\/div>\n <p>Tabakal\u0131 \u00f6rnekleme i\u00e7in her bireyin hangi tabakaya ait oldu\u011funu \u00f6nceden bilmek gerekir. \u00d6\u011frenci bilgi sistemimiz bize her \u00f6\u011frencinin fak\u00fcltesini veriyor \u2014 bu y\u00fczden tabakalama yapabiliyoruz. E\u011fer bu bilgi olmasayd\u0131, tabakalamaya ge\u00e7emezdik.<\/p>\n <\/div>\n\n <div class=\"bridge\">\n <span class=\"bridge-icon\">\ud83e\udd14<\/span>\n Peki ya elimizde \u00f6\u011frenci listesi de\u011fil de yaln\u0131zca \u015fubelerin listesi olsayd\u0131? Binlerce bireyden de\u011fil de do\u011fal gruplardan \u00f6rneklem alsayd\u0131k?\n <\/div>\n\n <!-- 2.3 K\u00fcme -->\n <h3 id=\"kume\">\n <div class=\"method-badge\"><span class=\"method-badge-num\">3<\/span>K\u00fcme \u00d6rneklemesi<\/div>\n <\/h3>\n\n <p>Bazen evreni olu\u015fturan bireylerin listesine sahip olmak m\u00fcmk\u00fcn olmayabilir; ama bu bireylerin do\u011fal olarak ait olduklar\u0131 <strong>gruplar\u0131n listesine<\/strong> sahip olabiliriz. \u0130\u015fte bu durumda <strong>k\u00fcme \u00f6rneklemesi<\/strong> devreye girer.<\/p>\n\n <p>Bizim senaryomuzda her fak\u00fcltede 10’ar \u015fube var; toplam 40 \u015fube. T\u00fcm \u00f6\u011frencilerin listesine eri\u015fimimiz olmad\u0131\u011f\u0131n\u0131, ama \u015fubelerin listesine sahip oldu\u011fumuzu varsayal\u0131m. Ne yapabiliriz? Bu 40 \u015fubenin bir k\u0131sm\u0131n\u0131 rastgele se\u00e7eriz ve <strong>se\u00e7ilen \u015fubelerdeki t\u00fcm \u00f6\u011frencileri<\/strong> \u00e7al\u0131\u015fmam\u0131za dahil ederiz. \u015eubelere <strong>k\u00fcme<\/strong> diyoruz.<\/p>\n\n <p>K\u00fcme \u00f6rneklemesi \u00f6zellikle <strong>co\u011frafi olarak geni\u015f alanlara<\/strong> yay\u0131lm\u0131\u015f evrenlerde b\u00fcy\u00fck kolayl\u0131k sa\u011flar. T\u00fcrkiye’deki t\u00fcm ilkokul \u00f6\u011frencilerini ara\u015ft\u0131r\u0131yorsan\u0131z, \u00f6nce okullar\u0131 (k\u00fcme) rastgele se\u00e7ip sonra se\u00e7ilen okullara gitmek, 81 il boyunca da\u011f\u0131lm\u0131\u015f her \u00f6\u011frenciyi tek tek bulmaktan \u00e7ok daha pratiktir.<\/p>\n\n <div class=\"box box-ok\">\n <div class=\"box-title\">\u2705 Tabakal\u0131 ile K\u00fcme \u00d6rneklemesinin Fark\u0131<\/div>\n <p><strong>Tabakal\u0131 \u00f6rneklemede<\/strong> her tabakadan bireyler se\u00e7ilir; k\u00fcme \u00f6rneklemesinde ise <strong>\u00f6nce k\u00fcmeler se\u00e7ilir<\/strong>, sonra se\u00e7ilen k\u00fcmelerdeki bireyler al\u0131n\u0131r \u2014 se\u00e7ilmeyen k\u00fcmelerden kimse dahil edilmez.<\/p>\n <p>Tabakalamada tabakalar <strong>homojen<\/strong> olmal\u0131d\u0131r \u2014 yani tabaka i\u00e7indeki bireyler birbirine benzer, tabakalar birbirinden farkl\u0131 olmal\u0131d\u0131r. K\u00fcme \u00f6rneklemesinde ise k\u00fcmeler <strong>heterojen<\/strong> olmal\u0131d\u0131r \u2014 yani her k\u00fcme evreni minyat\u00fcr olarak yans\u0131tabilmelidir.<\/p>\n <\/div>\n\n <p><strong>Dezavantaj\u0131 nedir?<\/strong> Ayn\u0131 \u015fubedeki \u00f6\u011frenciler, tamamen farkl\u0131 \u015fubelerden gelen \u00f6\u011frencilere k\u0131yasla birbirlerine daha \u00e7ok benzeyebilir (ayn\u0131 hocalar\u0131 var, ayn\u0131 s\u0131n\u0131f\u0131 payla\u015f\u0131yorlar). Bu durum, sanki ba\u011f\u0131ms\u0131z 200 ayr\u0131 ki\u015fiden de\u011fil de daha az say\u0131da ba\u011f\u0131ms\u0131z g\u00f6zlemden veri toplam\u0131\u015f gibi bir etki yarat\u0131r. \u0130statistikte buna <strong>tasar\u0131m etkisi<\/strong> denir.<\/p>\n\n <div class=\"code-wrap\">\n <div class=\"code-header\">\n <span class=\"code-lang\">R<\/span>\n <button class=\"code-copy\" onclick=\"copyCode(this)\">Kopyala<\/button>\n <\/div>\n<pre><span class=\"cm\"># \u2500\u2500 K\u00fcme \u00d6rneklemesi \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"cm\"># 40 \u015fubeden 8'ini rastgele se\u00e7iyoruz.<\/span>\n<span class=\"cm\"># Se\u00e7ilen \u015fubelerdeki T\u00dcM \u00f6\u011frenciler \u00f6rnekleme giriyor.<\/span>\n\n<span class=\"fn\">set.seed<\/span>(<span class=\"num\">42<\/span>)\n<span class=\"va\">tum_subeler<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">unique<\/span>(<span class=\"va\">evren<\/span><span class=\"op\">$<\/span><span class=\"va\">sube<\/span>) <span class=\"cm\"># 40 \u015fubenin listesi<\/span>\n\n<span class=\"va\">secilen_subeler<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">sample<\/span>(<span class=\"va\">tum_subeler<\/span>, <span class=\"pn\">size<\/span> <span class=\"op\">=<\/span> <span class=\"num\">8<\/span>)\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Se\u00e7ilen \u015fubeler:\\n'<\/span>)\n<span class=\"fn\">print<\/span>(<span class=\"va\">secilen_subeler<\/span>)\n\n<span class=\"va\">kume<\/span> <span class=\"op\"><-<\/span> <span class=\"va\">evren<\/span> <span class=\"op\">%>%<\/span>\n <span class=\"fn\">filter<\/span>(<span class=\"va\">sube<\/span> <span class=\"op\">%in%<\/span> <span class=\"va\">secilen_subeler<\/span>)\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\\nToplam \u00f6rneklem b\u00fcy\u00fckl\u00fc\u011f\u00fc:'<\/span>, <span class=\"fn\">nrow<\/span>(<span class=\"va\">kume<\/span>), <span class=\"str\">'ki\u015fi\\n'<\/span>)\n<span class=\"cm\"># Not: \u015eube b\u00fcy\u00fckl\u00fckleri farkl\u0131 oldu\u011fundan tam 200 olmayabilir.<\/span>\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Fak\u00fclte da\u011f\u0131l\u0131m\u0131 (k\u00fcme):\\n'<\/span>)\n<span class=\"fn\">print<\/span>(<span class=\"fn\">table<\/span>(<span class=\"va\">kume<\/span><span class=\"op\">$<\/span><span class=\"va\">fakulte<\/span>))\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\\nOrtalama \u00e7al\u0131\u015fma s\u00fcresi:'<\/span>, <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">kume<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>), <span class=\"str\">'saat\/hafta\\n'<\/span>)<\/pre>\n <\/div>\n\n <p>Dikkat edin: hangi \u015fubelerin se\u00e7ildi\u011fine ba\u011fl\u0131 olarak fak\u00fclte da\u011f\u0131l\u0131m\u0131 her seferinde farkl\u0131 \u00e7\u0131kabilir. E\u011fer \u015fans eseri T\u0131p \u015fubeleri se\u00e7ilmezse, bu fak\u00fclte hi\u00e7 temsil edilmez. Bu, k\u00fcme \u00f6rneklemesinin temel riskidir.<\/p>\n\n <div class=\"bridge\">\n <span class=\"bridge-icon\">\ud83e\udd14<\/span>\n Peki elimizde tam bir liste var ama 10.000 ki\u015fiyi tek tek numaraland\u0131r\u0131p \u00e7ekim yapmak zahmetli geliyorsa? Daha pratik bir yol yok mu?\n <\/div>\n\n <!-- 2.4 Sistematik -->\n <h3 id=\"sistematik\">\n <div class=\"method-badge\"><span class=\"method-badge-num\">4<\/span>Sistematik \u00d6rnekleme<\/div>\n <\/h3>\n\n <p>Sistematik \u00f6rnekleme, tam da bu durumda i\u015fe yarayan basit ve zarif bir y\u00f6ntemdir. Evren listesini <strong>k<\/strong> e\u015fit par\u00e7aya b\u00f6lersiniz; ilk k birim aras\u0131ndan <strong>bir ba\u015flang\u0131\u00e7 noktas\u0131<\/strong> rastgele se\u00e7ersiniz; oradan itibaren <strong>her k’\u0131nc\u0131 birimi<\/strong> al\u0131rs\u0131n\u0131z.<\/p>\n\n <p>Bizim senaryomuzda: 10.000 \u00f6\u011frenciden 200 se\u00e7ece\u011fiz. Ad\u0131m aral\u0131\u011f\u0131: <strong>k = 10.000 \/ 200 = 50.<\/strong> 1 ile 50 aras\u0131ndan rastgele bir ba\u015flang\u0131\u00e7 noktas\u0131 se\u00e7iyoruz, diyelim ki 17 \u00e7\u0131kt\u0131. O zaman \u00f6rneklememiz \u015fu ki\u015filerden olu\u015fur: 17, 67, 117, 167, 217… ve b\u00f6yle devam eder.<\/p>\n\n <div class=\"box box-warn\">\n <div class=\"box-title\">\u26a0\ufe0f Dikkat: Listedeki Gizli D\u00f6ng\u00fcsel Yap\u0131lar<\/div>\n <p>Sistematik \u00f6rneklemede tek tehlike, listenizin <strong>periyodik bir \u00f6r\u00fcnt\u00fc<\/strong> bar\u0131nd\u0131rmas\u0131d\u0131r. Diyelim ki \u00f6\u011frenci listesi her 50 ki\u015fide bir b\u00f6l\u00fcm ba\u015fkan\u0131yla ba\u015flayarak d\u00fczenlenmi\u015f. Her 50’nci ki\u015fiyi al\u0131rsan\u0131z, \u00f6rnekleminiz tamamen b\u00f6l\u00fcm ba\u015fkanlar\u0131ndan olu\u015fur! Bu durumda k ad\u0131m aral\u0131\u011f\u0131n\u0131 de\u011fi\u015ftirin ya da listeyi \u00f6nce rastgele s\u0131ralay\u0131n.<\/p>\n <\/div>\n\n <div class=\"code-wrap\">\n <div class=\"code-header\">\n <span class=\"code-lang\">R<\/span>\n <button class=\"code-copy\" onclick=\"copyCode(this)\">Kopyala<\/button>\n <\/div>\n<pre><span class=\"cm\"># \u2500\u2500 Sistematik \u00d6rnekleme \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"fn\">set.seed<\/span>(<span class=\"num\">42<\/span>)\n<span class=\"va\">N<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">nrow<\/span>(<span class=\"va\">evren<\/span>) <span class=\"cm\"># 10.000<\/span>\n<span class=\"va\">n<\/span> <span class=\"op\"><-<\/span> <span class=\"num\">200<\/span>\n<span class=\"va\">k<\/span> <span class=\"op\"><-<\/span> <span class=\"va\">N<\/span> <span class=\"op\">\/<\/span> <span class=\"va\">n<\/span> <span class=\"cm\"># Ad\u0131m aral\u0131\u011f\u0131: 50<\/span>\n\n<span class=\"va\">baslangic<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">sample<\/span>(<span class=\"num\">1<\/span><span class=\"op\">:<\/span><span class=\"va\">k<\/span>, <span class=\"pn\">size<\/span> <span class=\"op\">=<\/span> <span class=\"num\">1<\/span>) <span class=\"cm\"># 1-50 aras\u0131ndan rastgele<\/span>\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Ba\u015flang\u0131\u00e7 noktas\u0131:'<\/span>, <span class=\"va\">baslangic<\/span>, <span class=\"str\">'\\n'<\/span>)\n\n<span class=\"va\">indeksler<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">seq<\/span>(<span class=\"pn\">from<\/span> <span class=\"op\">=<\/span> <span class=\"va\">baslangic<\/span>, <span class=\"pn\">to<\/span> <span class=\"op\">=<\/span> <span class=\"va\">N<\/span>, <span class=\"pn\">by<\/span> <span class=\"op\">=<\/span> <span class=\"va\">k<\/span>)\n<span class=\"va\">sistematik<\/span> <span class=\"op\"><-<\/span> <span class=\"va\">evren<\/span>[<span class=\"va\">indeksler<\/span>, ]\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\u00d6rneklem b\u00fcy\u00fckl\u00fc\u011f\u00fc:'<\/span>, <span class=\"fn\">nrow<\/span>(<span class=\"va\">sistematik<\/span>), <span class=\"str\">'\\n'<\/span>)\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'Fak\u00fclte da\u011f\u0131l\u0131m\u0131:\\n'<\/span>)\n<span class=\"fn\">print<\/span>(<span class=\"fn\">table<\/span>(<span class=\"va\">sistematik<\/span><span class=\"op\">$<\/span><span class=\"va\">fakulte<\/span>))\n\n<span class=\"fn\">cat<\/span>(<span class=\"str\">'\\nOrtalama \u00e7al\u0131\u015fma s\u00fcresi:'<\/span>,\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">sistematik<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>), <span class=\"str\">'saat\/hafta\\n'<\/span>)<\/pre>\n <\/div>\n\n <!-- 2.5 Kar\u015f\u0131la\u015ft\u0131rma -->\n <h3 id=\"karsilastirma\">D\u00f6rt Y\u00f6ntemi Kar\u015f\u0131la\u015ft\u0131ral\u0131m<\/h3>\n\n <p>\u015eimdiye kadar ayn\u0131 evrenden d\u00f6rt farkl\u0131 y\u00f6ntemle 200 ki\u015filik \u00f6rneklem \u00e7ektik. Ger\u00e7ek evren ortalamas\u0131n\u0131n 26,33 saat\/hafta oldu\u011funu biliyoruz. Hangi y\u00f6ntem bu ger\u00e7e\u011fe ne kadar yakla\u015ft\u0131?<\/p>\n\n <div class=\"code-wrap\">\n <div class=\"code-header\">\n <span class=\"code-lang\">R<\/span>\n <button class=\"code-copy\" onclick=\"copyCode(this)\">Kopyala<\/button>\n <\/div>\n<pre><span class=\"cm\"># \u2500\u2500 D\u00f6rt Y\u00f6ntemin Kar\u015f\u0131la\u015ft\u0131rmas\u0131 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500<\/span>\n<span class=\"va\">gercek_ort<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">mean<\/span>(<span class=\"va\">evren<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>)\n\n<span class=\"va\">sonuclar<\/span> <span class=\"op\"><-<\/span> <span class=\"fn\">data.frame<\/span>(\n <span class=\"pn\">Yontem<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">c<\/span>(<span class=\"str\">'Ger\u00e7ek Evren'<\/span>, <span class=\"str\">'Basit Rastgele'<\/span>, <span class=\"str\">'Tabakal\u0131'<\/span>, <span class=\"str\">'K\u00fcme'<\/span>, <span class=\"str\">'Sistematik'<\/span>),\n <span class=\"pn\">Ortalama<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">c<\/span>(\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">evren<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">bro<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">tabakali<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">kume<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">sistematik<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>), <span class=\"num\">2<\/span>)\n ),\n <span class=\"pn\">Sapma<\/span> <span class=\"op\">=<\/span> <span class=\"fn\">c<\/span>(\n <span class=\"num\">0<\/span>,\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">bro<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>) <span class=\"op\">-<\/span> <span class=\"va\">gercek_ort<\/span>, <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">tabakali<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>) <span class=\"op\">-<\/span> <span class=\"va\">gercek_ort<\/span>, <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">kume<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>) <span class=\"op\">-<\/span> <span class=\"va\">gercek_ort<\/span>, <span class=\"num\">2<\/span>),\n <span class=\"fn\">round<\/span>(<span class=\"fn\">mean<\/span>(<span class=\"va\">sistematik<\/span><span class=\"op\">$<\/span><span class=\"va\">calisma_suresi<\/span>) <span class=\"op\">-<\/span> <span class=\"va\">gercek_ort<\/span>, <span class=\"num\">2<\/span>)\n )\n)\n\n<span class=\"fn\">print<\/span>(<span class=\"va\">sonuclar<\/span>)<\/pre>\n <\/div>\n\n <p>Bu t\u00fcr bir kar\u015f\u0131la\u015ft\u0131rmay\u0131 tek bir rastgele \u00e7ekimde yapmak yan\u0131lt\u0131c\u0131 olabilir \u2014 sonu\u00e7ta her seferinde farkl\u0131 \u00f6\u011frenciler se\u00e7ilecektir. <strong>Ger\u00e7ek fark, y\u00f6ntemi y\u00fczlerce kez tekrarlad\u0131\u011f\u0131n\u0131zda ortaya \u00e7\u0131kar:<\/strong> tabakal\u0131 \u00f6rnekleme, evren i\u00e7inde anlaml\u0131 alt gruplar varken tutarl\u0131 bi\u00e7imde daha isabetli sonu\u00e7lar verir.<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Y\u00f6ntem<\/th>\n <th>Liste Gerekir mi?<\/th>\n <th>En G\u00fc\u00e7l\u00fc Oldu\u011fu Durum<\/th>\n <th>Temel Riski<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td>Basit Rastgele<\/td><td>Evet \u2014 bireyler<\/td><td>Homojen evrenler<\/td><td>K\u00fc\u00e7\u00fck gruplar temsil edilmeyebilir<\/td><\/tr>\n <tr><td>Tabakal\u0131<\/td><td>Evet \u2014 bireyler + tabaka bilgisi<\/td><td>Alt gruplar farkl\u0131la\u015f\u0131yorsa<\/td><td>Tabaka bilgisi bilinmiyorsa uygulanamaz<\/td><\/tr>\n <tr><td>K\u00fcme<\/td><td>Evet \u2014 k\u00fcmeler<\/td><td>Bireysel liste yoksa \/ saha geni\u015f yay\u0131l\u0131ml\u0131ysa<\/td><td>K\u00fcmeler benze\u015firse hassasiyet d\u00fc\u015fer<\/td><\/tr>\n <tr><td>Sistematik<\/td><td>Evet \u2014 bireyler<\/td><td>Liste mevcutsa ve d\u00f6ng\u00fcsel yap\u0131 yoksa<\/td><td>Periyodik liste yanl\u0131l\u0131k yarat\u0131r<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <!-- 3. Ara\u015ft\u0131rma Grubu Se\u00e7imi -->\n <h2 id=\"arastirma-grubu\">3. Ara\u015ft\u0131rma Grubu Se\u00e7imi: \u00d6rnekleme Olmayan Y\u00f6ntemler<\/h2>\n\n <p>\u015eimdiye kadar anlatt\u0131\u011f\u0131m\u0131z y\u00f6ntemlerin ortak \u00f6zelli\u011fi neydi? Hepsinde bir listemiz vard\u0131; hepsinde her bireyin se\u00e7ilme olas\u0131l\u0131\u011f\u0131 s\u0131f\u0131rdan b\u00fcy\u00fckt\u00fc; hepsinde bu olas\u0131l\u0131\u011f\u0131 hesaplayabiliyorduk. Bu \u00f6zellikler sayesinde buldu\u011fumuz sonu\u00e7lar\u0131 evrene genelleyebiliyorduk.<\/p>\n\n <p><strong>Ya bunlar\u0131n hi\u00e7biri m\u00fcmk\u00fcn de\u011filse?<\/strong><\/p>\n\n <p>Ger\u00e7ek hayatta liste her zaman elimizin alt\u0131nda olmayabilir. Ula\u015f\u0131lmas\u0131 g\u00fc\u00e7 bir toplulu\u011fu ara\u015ft\u0131r\u0131yorsunuz, ya da ke\u015fifsel bir \u00e7al\u0131\u015fma yap\u0131yorsunuz, ya da b\u00fct\u00e7eniz \u00e7ok k\u0131s\u0131tl\u0131. Bu durumlarda ara\u015ft\u0131rmac\u0131lar farkl\u0131 y\u00f6ntemlere ba\u015fvurur. Ancak bu y\u00f6ntemler, istatistiksel anlamda <strong>\u00f6rnekleme de\u011fildir.<\/strong> Bireylerin se\u00e7ilme olas\u0131l\u0131\u011f\u0131 ya bilinmemekte ya da herkese e\u015fit de\u011fildir. Bu nedenle elde edilen bulgular evrene genellenemez.<\/p>\n\n <p>Bu y\u00f6ntemlere <strong>ara\u015ft\u0131rma grubu se\u00e7imi<\/strong> demek daha do\u011frudur. Kendi ama\u00e7lar\u0131 i\u00e7in son derece de\u011ferlidirler \u2014 ama onlar\u0131 “\u00f6rnekleme” diye sunmak yan\u0131lt\u0131c\u0131 olur.<\/p>\n\n <!-- 3.1 Kolayda -->\n <h3 id=\"kolayda\">3.1. Kolayda (Uygunluk) Se\u00e7imi<\/h3>\n\n <p>En basit ve en yayg\u0131n y\u00f6ntemdir: ara\u015ft\u0131rmac\u0131, <strong>en kolay ula\u015fabilece\u011fi<\/strong> bireyleri \u00e7al\u0131\u015fmaya dahil eder.<\/p>\n\n <p><strong>\u00dcniversite senaryomuzdaki kar\u015f\u0131l\u0131\u011f\u0131:<\/strong> \u00dcniversitenin kantininde anket da\u011f\u0131t\u0131yorsunuz. Oraya gelen \u00f6\u011frencileri doldurttunuz, hepsi bu. H\u0131zl\u0131, ucuz, pratik. Ama o anda kantinde olmayan, k\u00fct\u00fcphanede ders \u00e7al\u0131\u015fan, evde kalan ya da farkl\u0131 bir kamp\u00fcste bulunan \u00f6\u011frenciler bu ara\u015ft\u0131rmaya hi\u00e7 giremeyecek.<\/p>\n\n <p>Kolayda se\u00e7iminin hakl\u0131 kullan\u0131m alanlar\u0131 vard\u0131r:<\/p>\n <ul>\n <li><strong>Pilot \u00e7al\u0131\u015fmalar:<\/strong> Anketinizin anla\u015f\u0131l\u0131p anla\u015f\u0131lmad\u0131\u011f\u0131n\u0131 test etmek i\u00e7in 20 ki\u015fiye ihtiyac\u0131n\u0131z var; temsil kayg\u0131s\u0131 \u015fu an \u00f6nemli de\u011fil.<\/li>\n <li><strong>\u00d6n ke\u015fif:<\/strong> Konuya ilk kez yakla\u015f\u0131yorsunuz, neyi ara\u015ft\u0131raca\u011f\u0131n\u0131z\u0131 bile tam bilmiyorsunuz.<\/li>\n <li><strong>Zaman ve b\u00fct\u00e7e k\u0131s\u0131t\u0131:<\/strong> K\u00fc\u00e7\u00fck \u00f6l\u00e7ekli, ke\u015fifsel bir \u00e7al\u0131\u015fma yap\u0131yorsunuz ve sonu\u00e7lar\u0131 genelleme iddias\u0131nda olmayacaks\u0131n\u0131z.<\/li>\n <\/ul>\n\n <!-- 3.2 Kartopu -->\n <h3 id=\"kartopu\">3.2. Kartopu (Zincirleme) Se\u00e7imi<\/h3>\n\n <p>Ara\u015ft\u0131rmac\u0131 \u00f6nce k\u00fc\u00e7\u00fck bir grupla ba\u015flar; bu ilk kat\u0131l\u0131mc\u0131lar, ara\u015ft\u0131rmac\u0131ya ba\u015fka bireyleri tan\u0131\u015ft\u0131r\u0131r; onlar da ba\u015fkalar\u0131n\u0131… \u00d6rneklem bir kartopu gibi b\u00fcy\u00fcr.<\/p>\n\n <p><strong>Ne zaman vazge\u00e7ilmezdir?<\/strong> Ara\u015ft\u0131r\u0131lmas\u0131 g\u00fc\u00e7, gizli ya da marjinal topluluklar s\u00f6z konusu oldu\u011funda. Belirli bir kronik hastal\u0131\u011fa sahip bireyleri, belirli bir mesleki toplulu\u011fu ya da sosyal damgalanma nedeniyle kendini gizleyen gruplar\u0131 ara\u015ft\u0131r\u0131yorsan\u0131z, bu bireylerin listesi zaten mevcut de\u011fildir. Kartopu y\u00f6ntemi, bu durumlarda tek ger\u00e7ek\u00e7i se\u00e7enek olabilir.<\/p>\n\n <p><strong>S\u0131n\u0131rl\u0131l\u0131\u011f\u0131:<\/strong> A\u011f yap\u0131s\u0131 homojenli\u011fe yol a\u00e7ar. \u0130nsanlar genellikle kendilerine benzeyen bireyleri tan\u0131r ve \u00f6nerir. Bu nedenle \u00f6rneklem, evreni de\u011fil belirli bir sosyal \u00e7evrevi yans\u0131t\u0131yor olabilir.<\/p>\n\n <!-- 3.3 Kota -->\n <h3 id=\"kota\">3.3. Kota Se\u00e7imi<\/h3>\n\n <p>Ara\u015ft\u0131rmac\u0131 belli kotalar belirler: \u00f6rne\u011fin 100 kad\u0131n, 100 erkek; ya da her fak\u00fclteden 50 ki\u015fi. Bu kotalara ula\u015fana dek uygun bireyleri se\u00e7er.<\/p>\n\n <p><strong>Tabakal\u0131 \u00f6rneklemeden fark\u0131 nedir?<\/strong> G\u00f6r\u00fcn\u00fc\u015fte benzer, ama temel bir fark var: tabakal\u0131 \u00f6rneklemede her tabakadan se\u00e7im <strong>rastgele<\/strong> yap\u0131l\u0131r. Kota se\u00e7iminde ise ara\u015ft\u0131rmac\u0131 kotay\u0131 doldurana kadar <strong>eline ge\u00e7eni<\/strong> al\u0131r. Kantinde kar\u015f\u0131la\u015ft\u0131\u011f\u0131 ilk 50 kad\u0131n\u0131 ald\u0131ktan sonra “kad\u0131n kotam doldu” der ve devam eder. Bu se\u00e7im rastgele de\u011fildir; dolay\u0131s\u0131yla olas\u0131l\u0131kl\u0131 da de\u011fildir.<\/p>\n\n <!-- 3.4 Ama\u00e7l\u0131 -->\n <h3 id=\"amacli\">3.4. Ama\u00e7l\u0131 (Kas\u0131tl\u0131) Se\u00e7im<\/h3>\n\n <p>Ara\u015ft\u0131rmac\u0131, ara\u015ft\u0131rma sorusu i\u00e7in en fazla bilgi sa\u011flayaca\u011f\u0131n\u0131 <strong>bilerek ve isteyerek<\/strong> d\u00fc\u015f\u00fcnd\u00fc\u011f\u00fc bireyleri se\u00e7er. Bu tamamen ara\u015ft\u0131rmac\u0131n\u0131n yarg\u0131s\u0131na dayan\u0131r.<\/p>\n\n <p><strong>\u00dcniversite senaryomuzdaki kar\u015f\u0131l\u0131\u011f\u0131:<\/strong> Her fak\u00fclteden en y\u00fcksek not ortalamas\u0131na sahip 5 ve en d\u00fc\u015f\u00fck not ortalamas\u0131na sahip 5 \u00f6\u011frenciyi se\u00e7iyorsunuz; \u00e7\u00fcnk\u00fc <em>“\u00e7al\u0131\u015fma s\u00fcresi ile akademik ba\u015far\u0131 aras\u0131ndaki ili\u015fkiyi derinlemesine anlamak”<\/em> istiyorsunuz. Bu ama\u00e7 i\u00e7in mant\u0131kl\u0131 bir se\u00e7im. Ama bu \u00f6\u011frenciler \u00fcniversitedeki “ortalama \u00f6\u011frenciyi” temsil etmiyor.<\/p>\n\n <p><strong>Ne zaman tercih edilir?<\/strong> Nitel ara\u015ft\u0131rmalarda, vaka \u00e7al\u0131\u015fmalar\u0131nda, derinlemesine g\u00f6r\u00fc\u015fmelerde. Az say\u0131da kat\u0131l\u0131mc\u0131yla \u00e7ok derin bilgi elde etmek istedi\u011finizde.<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Y\u00f6ntem<\/th>\n <th>Nas\u0131l Se\u00e7ilir?<\/th>\n <th>G\u00fc\u00e7l\u00fc Yan\u0131<\/th>\n <th>Neden “\u00d6rnekleme” De\u011fil?<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td>Kolayda<\/td><td>En kolay ula\u015f\u0131lanlar<\/td><td>H\u0131z, d\u00fc\u015f\u00fck maliyet<\/td><td>Se\u00e7ilme olas\u0131l\u0131klar\u0131 e\u015fit de\u011fil ve bilinmiyor<\/td><\/tr>\n <tr><td>Kartopu<\/td><td>Kat\u0131l\u0131mc\u0131lar ba\u015fkalar\u0131n\u0131 \u00f6nerir<\/td><td>Ula\u015f\u0131lmas\u0131 zor gruplar<\/td><td>A\u011f d\u0131\u015f\u0131ndakiler hi\u00e7 se\u00e7ilemiyor<\/td><\/tr>\n <tr><td>Kota<\/td><td>Kota dolana dek uygun ki\u015filer<\/td><td>Grup da\u011f\u0131l\u0131m\u0131 kontrol edilebilir<\/td><td>Tabaka i\u00e7i se\u00e7im rastgele de\u011fil<\/td><\/tr>\n <tr><td>Ama\u00e7l\u0131<\/td><td>Ara\u015ft\u0131rmac\u0131 bilin\u00e7li se\u00e7er<\/td><td>Derin nitel bilgi<\/td><td>Se\u00e7im tamamen s\u00fcbjektif yarg\u0131ya dayal\u0131<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <!-- 4. Sonu\u00e7 -->\n <h2 id=\"sonuc\">4. Sonu\u00e7<\/h2>\n\n <p>Bu yaz\u0131n\u0131n en ba\u015f\u0131nda sordu\u011fumuz soruyla bitirelim: \u00f6rnekleme nedir ve ne de\u011fildir?<\/p>\n\n <p><strong>\u00d6rnekleme,<\/strong> evreni olu\u015fturan bireylerin listesine sahip olmay\u0131 ve bu listeden her bireyin se\u00e7ilme olas\u0131l\u0131\u011f\u0131n\u0131n s\u0131f\u0131rdan b\u00fcy\u00fck oldu\u011fu sistematik bir mekanizma kullanmay\u0131 gerektirir. Bu \u00f6n ko\u015fullar sa\u011fland\u0131\u011f\u0131nda, \u00f6rneklemden elde edilen bulgular evrene genellenebilir.<\/p>\n\n <p>Basit rastgele, tabakal\u0131, k\u00fcme ve sistematik \u00f6rnekleme \u2014 hepsi bu \u00f6n ko\u015fullar\u0131 kar\u015f\u0131lar. Aralar\u0131ndaki fark, evrene ve ara\u015ft\u0131rma sorusuna g\u00f6re hangisinin daha uygun oldu\u011fuyla ilgilidir: evrende yap\u0131sal alt gruplar var m\u0131? Bireysel liste mevcut mu? Saha geni\u015f bir co\u011frafyaya m\u0131 yay\u0131lm\u0131\u015f?<\/p>\n\n <p>Kolayda, kartopu, kota ve ama\u00e7l\u0131 se\u00e7im ise bu \u00f6n ko\u015fullar\u0131 kar\u015f\u0131lamaz. Bu onlar\u0131 “k\u00f6t\u00fc y\u00f6ntemler” yapmaz \u2014 ara\u015ft\u0131rman\u0131n amac\u0131na, kapsam\u0131na ve olanaklar\u0131na g\u00f6re son derece de\u011ferli se\u00e7enekler olabilirler. Ama bulgular\u0131n\u0131 “evrenin tamam\u0131na genellenebilir” olarak sunmak yan\u0131lt\u0131c\u0131 olur.<\/p>\n\n <div class=\"box box-info\">\n <div class=\"box-title\">\ud83d\udccb \u00d6zet: Kendinize \u015eu Sorular\u0131 Sorun<\/div>\n <ol style=\"padding-left:1.4rem; margin:0;\">\n <li>Evreni olu\u015fturan birimlerin bir listesine sahip miyim?<\/li>\n <li>Evrende anlaml\u0131 alt gruplar var m\u0131 ve bunlar\u0131n ayr\u0131 ayr\u0131 temsili \u00f6nemli mi?<\/li>\n <li>Bireysel liste yok ama do\u011fal gruplar\u0131n listesi var m\u0131?<\/li>\n <li>Bulgular\u0131m\u0131 evrene genellemek istiyor muyum, yoksa ke\u015fifsel bir \u00e7al\u0131\u015fma m\u0131 yap\u0131yorum?<\/li>\n <\/ol>\n <p style=\"margin-top:.8rem;\">Bu sorular\u0131n cevaplar\u0131, hangi y\u00f6ntemi se\u00e7ece\u011finizi b\u00fcy\u00fck \u00f6l\u00e7\u00fcde belirleyecektir.<\/p>\n <\/div>\n\n <\/article>\n<\/div><!-- \/page-wrap -->\n\n<footer class=\"site-footer\">\n <p><a href=\"\/\">istatistik.gen.tr<\/a> \u00b7 Bir proje kapsam\u0131nda yapay zeka taraf\u0131ndan otomatik olarak \u00fcretilmi\u015ftir.<\/p>\n<\/footer>\n\n<script>\n\/* \u2500\u2500 Kod kopyalama \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\nfunction copyCode(btn) {\n const pre = btn.closest('.code-wrap').querySelector('pre');\n const text = pre.innerText;\n navigator.clipboard.writeText(text).then(() => {\n btn.textContent = 'Kopyaland\u0131!';\n btn.classList.add('copied');\n setTimeout(() => {\n btn.textContent = 'Kopyala';\n btn.classList.remove('copied');\n }, 1800);\n });\n}\n\n\/* \u2500\u2500 Aktif TOC vurgulama \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 *\/\n\n<\/script>\n\n<\/body>\n<\/html>\n\n","protected":false},"excerpt":{"rendered":"<p>\u00d6rnekleme Y\u00f6ntemleri | istatistik.gen.tr istatistik.gen.tr \u0130statistik Rehberi Ara\u015ft\u0131rma Y\u00f6ntemleri \u00d6rnekleme Y\u00f6ntemleri \u00d6rneklem nedir, nas\u0131l se\u00e7ilir ve R ile nas\u0131l uygulan\u0131r? ~15 dakika okuma R kodu i\u00e7erir Ba\u015flang\u0131\u00e7\u2013Orta d\u00fczey \u0130\u00e7indekiler 1. \u00d6rnekleme Nedir? 2. Olas\u0131l\u0131kl\u0131 \u00d6rnekleme Y\u00f6ntemleri 2.1 Basit Rastgele \u00d6rnekleme 2.2 Tabakal\u0131 \u00d6rnekleme 2.3 K\u00fcme \u00d6rneklemesi 2.4 Sistematik \u00d6rnekleme 3. Ara\u015ft\u0131rma Grubu Se\u00e7imi 3.1 Kolayda…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":true,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-1274","post","type-post","status-publish","format-standard","hentry","category-genel"],"_links":{"self":[{"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=\/wp\/v2\/posts\/1274","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1274"}],"version-history":[{"count":3,"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=\/wp\/v2\/posts\/1274\/revisions"}],"predecessor-version":[{"id":1277,"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=\/wp\/v2\/posts\/1274\/revisions\/1277"}],"wp:attachment":[{"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1274"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1274"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.istatistik.gen.tr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1274"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}