psych_stats midterm 3 (1)

psych/stats midterm 3
With a population what is the denominator of standard deviation - CORRECT
ANSWER-N

With a sample what is the denominator of standard deviation - CORRECT
ANSWER-N - 1

when do you use t distributions - CORRECT ANSWER-when you don't know o
(standard deviation)

How does t distribution compare to z distribution - CORRECT ANSWER-t varies with
sample size, it is wider and flatter than the z distribution

degrees of freedom - CORRECT ANSWER-number of scores that are free to vary
when we estimate a population parameter from a sample

degrees of freedom for one sample t test - CORRECT ANSWER-N-1

when do we use the one sample t test - CORRECT ANSWER-one population, when
we know the means but not standard deviation

one sample t test - CORRECT ANSWER-(M - um)/sm

Sm - CORRECT ANSWER-s/sqrt (N)

when do you reject the null hypothesis - CORRECT ANSWER-if above or below the
crit values

how to calculate high and low for confidence interval - CORRECT ANSWER-+-t(Sm)
+M

cohens d - CORRECT ANSWER-(M-u)/s

small effect size - CORRECT ANSWER-0.2, 85%

medium effect size - CORRECT ANSWER-0.5, 67%

large effect size - CORRECT ANSWER-0.8, 53%

APA reporting statistics style - CORRECT ANSWER-t(df) = (t stat), p < (p val), d =
cohens

t(40) = 7.00, p < 0.001, d = 1.09