Contents
How do you compare samples with different sizes?
One way to compare the two different size data sets is to divide the large set into an N number of equal size sets. The comparison can be based on absolute sum of of difference. THis will measure how many sets from the Nset are in close match with the single 4 sample set.
Can sample sizes be different?
Unequally sized groups are common in research and may be the result of simple randomization, planned differences in group size or study dropouts. Unequal sample sizes can lead to: Unequal variances between samples, which affects the assumption of equal variances in tests like ANOVA.
Does Anova require equal sample sizes?
There is no equal sample size assumption for ANOVA. If your data satisfies the 3 assumptions (Normality, equality of variance and independence) you can run ANOVA. But if our sample size is very small (as in eg) the data may not satisfy assumptions and you will have to run Kruskall Wallis.
What to do when your sample size is too big?
Power. If you change your desired level of power, you will need fewer participants. Generally in social science research, a power of .80 is desired. If you have set your power level higher during your sample size calculations, try setting it at .80.
How to calculate Sample Size for a study?
Bearing this point in mind, there are different formulas to calculate sample size.2,3These formulas comprise several aspects which are listed below. Most sample size calculators available on the web have limited validity because they use a single formula – which is usually not divulged – to generate sample sizes for the studies.
What are the factors that affect sample size?
FACTORS THAT AFFECT SAMPLE SIZE The purpose of estimating the appropriate sample size is to produce studies capable of detecting clinically relevant differences. Bearing this point in mind, there are different formulas to calculate sample size.2,3These formulas comprise
How big of a sample do you need to do a regression?
Using G*Power (a sample size and power calculator) a simple linear regression with a medium effect size, an alpha of .05, and a power level of .80 requires a sample size of 55 individuals. Perhaps you were only able to collect 21 participants, in which case (according to G*Power), that would be enough to find a large effect with a power of .80.