Transcription of 19: Sample Size, Precision, and Power
{{id}} {{{paragraph}}}
Example: stock market
19: Sample Size, Precision, and Power
Page (C:\DATA\StatPrimer\ B. Gerstman 5/15/03)nsd=422( )nsdd=422( )nsdp=422( )19: Sample Size, Precision, and PowerA study that is insufficiently precise or lacks the Power to reject a false null hypothesis is a waste of time andmoney. A study that collects too much data is also wasteful. Therefore, before collecting data, it is essential todetermine the Sample size requirements of a study. Before calculating the Sample size requirements of a study youmust address some questions. For example: Do you want to learn about a mean? a mean difference? a proportion? a proportion (risk) ratio? an odds ratio? aslope? Do you want to estimate something with a given precision or do you want to test something with a givenpower?
For a one-sample t test ∆ = µ ! µ 0. For a paired-sample t test ∆ = µ d. For an independent t test ∆ = µ 1 − µ 2. These values are NOT calculated but come from conjecture. σ represents the standard deviation of the variable as estimated by s, s d, or s p depending on whether data are from a single sample, paired samples, or ...
Loading..
Tags:
Information
Domain:
Source:
Link to this page:
Please notify us if you found a problem with this document: