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Alma1
Level III

pooled /unpooled t test

Hi 

What is the appropriate two sample t procedure for the summary below milking periods of cow breeds pooled/unpooled (Welch) using R?

Frisian cow          Xbar=342.5           S1=10.2                 n1=126

Jersey cow         Xbar =348.6           S2=12.2                 n2=39

Construct 95% confidence interval for µ1-µ2

Give proper interpretation of the interval

Thanks

10 REPLIES 10
Georg
Level VII

Re: pooled /unpooled t test

@Alma1  have a look at

help -> sample data -> Calculators -> Hypothesis test for two means

and follow the workflow (or excecute the script below).

 

For learning Purpose I would also recommend to construct a data table from the summary statistics and perform the t-Test from menu Analysis -> Fit y by x, and Read the explanations JMP gives.

 

 

Names default to here(1);
open("$SAMPLE_SCRIPTS\Calculators\TestTwoSampleMeans.jsl");
Georg