HILFIGER
Forum Senior
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Are selection bias and sampling bias synonymous?
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| dreamer
Forum Elite
Topics: 52
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in 2004 kaplan notes page 7:
selection bias(sampling bias): the sample selected is not representative of the population.
in fa , selection bias: nonrandom assignment to study group. for instance,in a study, more serious sick pt would choose to take the drug instead of placebo thus make it more difficult to show a positive effect of the drug. or the physician will put all the most serious cases into the drug group.
sampling bias : subjects are not representative,therefore results are not generalizable. for example, predicting rates of heart disease by gathering subjects from a local health club
in my opinion, they are still slightly different although kaplan put them together. selection bias is the mistake by grouping.the sample you pick are right: but you just dont group them at random. in sample bias, you make mistake even before you group pp. the subjects are just not generlizable.....like you pick all the pp from healthy club.
actually, i am not sure at all and a bit confuse too .plz correct me if i am wrong.
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| HILFIGER
Forum Senior
Topics: 22
Posts: 195
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I think you are right
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