Ch 13--Student's t for single samples.

1. Introduction:

2. When population is unknown















A. Generating hypotheses











B. Calculating the statistic









C. Evaluate the statistic









3. The sampling distribution of t

A. Definition of the t distribution is the same for the definition of any sampling distribution--it is a probability distribution of all the possible values of t that could occur from all possible samples of a given N.

B. Degrees of Freedom

C. t/z compared





D. Tcrit







4. Computation of tobt, using original scores





























E.g.,

X

9.22

8.00

7.67

8.00

3.78

5.89

8.33

7.44

6.78

3.44





4. 2nd use of t: Confidence intervals for

A. Confidence interval: a range of values that probably contains the .





B. It's Confidence limits are the values that bound this range.





C. 95% Confidence interval







D. General Confidence Intervals

















5. 3rd use of t: testing the significance of Pearson r

A. Hypotheses



B. Calculate statistic



C. Evaluate results

i. sampling distribution of r, df=N-2





Statistics