Page 179 - สถิติทางวิทยาศาสตร์สุขภาพ เพื่อการวิจัย

µ—«Õ¬à“ß∑’Ë 10.3

„π°“√ª√–‡¡‘𧫓¡√Ÿâ‡√◊ËÕߧ«“¡ª≈Õ¥¿—¬„π°“√¢—∫¢’Ë√∂®—°√¬“π¬πµå°àÕπ·≈–À≈—ß

°“√Ωñ°Õ∫√¡µâÕß„™âµ—«Õ¬à“ß¢π“¥‡∑à“‰√ ∂⓺≈√“¬ß“π«‘®—¬∑’˺à“π¡“· ¥ß„πµ“√“ßµàÕ‰ªπ’È

À≈—ßΩñ°¡’§«“¡√Ÿâ
‰¡àæÕ æÕ
6 14
‰¡àæÕ
ab
°àÕπΩñ°¡’§«“¡√Ÿâ
cd
æÕ
4 12

®“°ß“π«‘®—¬∑’˺à“π¡“®–‰¥â«à“ b = 14, c = 4, n = a + b + c + d = 36

4
p = = 0.111 ‡æ√“–§à“ c ‡≈Á°°«à“§à“ b
36
°”Àπ¥„À⇪ìπ°“√∑¥ Õ∫¥â“π‡¥’¬« Ò = 0.05 Æ Z = 1.65
0.05
Õ”π“®°“√∑¥ Õ∫ = 0.9 Æ Z = 1.28
0.1
2
È 2 ˘
Í Z b + 1 + Z Ä b + 1Â - pÄ b - 1Â ˙
Í a c b c c ˙
n= Î ˚
b 2
pÄ - 1Â
c

È 2 ˘ 2
Í 14 + 1 + 14 + 14 - ˙
Í 165. 4 1 28. Ä 4 1 - Â 0 111. Ä 4 1Â ˙
Í Î ˙ ˚
=
14 2
0 111. Ä - 1Â
4

= 52 §π

¢π“¥µ—«Õ¬à“ß∑’˵âÕß„™â„π°“√»÷°…“‡∑à“°—∫ 52 §π

b b 14
§à“ ‡ªìπ§à“∑’Ëπ—°«‘®—¬ “¡“√∂ª√—∫‰¥â ‡™àπ ®“°µ—«Õ¬à“ß = = 3.5 ∂â“π—°«‘®—¬
c c 4
§‘¥«à“«‘∏’°“√Ωñ°Õ∫√¡∑’Ë„™â„π°“√«‘®—¬®–„Àâº≈∑’Ë¥’°«à“∑’ˇ§¬¡’°“√ Õπ„πß“π«‘®—¬∑’˺à“π¡“ (∑’Ëπ”§à“ b, c
b
¡“„™â) Õ“®°”Àπ¥„Àâ§à“ ‡ªìπ 4 À√◊Õ 4.5 °Á‰¥â
c

178 ∫∑∑’Ë 10 «‘∏’§”π«≥¢π“¥µ—«Õ¬à“ß„π°“√»÷°…“·∫∫µà“ßÊ

∫∑∑’Ë10 178 10/7/09, 11:44 AM