Z-scores, T-tests, etc Flashcards
raw score, sample mean, SD,
Z-score
(raw score-s.mean)/SD
z-score
SD, number of samples
Standard error
it gives an estimate of the precision of the sample mean
standard error
sample mean, hypothesized population mean, population SD, sample size
Z-test
How to find a raw score from a z-score?
raw score= (Z-score*SD)+ s.mean
(s.mean - p.mean)/(pop standard deviation/√sample size)
Z-test
Do we use Z-score or T-test when the population Standard Deviation is unknown?
T-test
Do we use Z-score or T-test when the sample size is smaller than 30?
T-test
(sample mean-population mean)/(sample standard deviation/√sample size)
T-test
Which way does the <> face for one way decision criteria?
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How do you calculate the SD for a sample?
Use excel lol
what are the steps for such a problem: For a normally distributed set of scores, what percentage of raw scores fall between a z-score of +0.83 and a z-score of +2.15?
- find p-value in z-table for both
2. smaller number- larger number
Does a z p-value show the percentage of all the scores on the left or on the right of the score
on the left of the score
How to find the decision criteria, z-tests and t-tests?
Look in the z/t table for score that correlates to the alpha/significance level you’re searching for. (.05, .025, etc)
