psyc 60 hypothesis testing concepts (single sample z & t)

Question 1

____ is the probability that the test will lead to a Type I Error.

Accepted Answer

alpha level

Question 2

if other factors are held constant, increasing the size of the sample increases likelihood of rejecting null hypothesis

Accepted Answer

True

Question 3

increasing the alpha level from .01 to .05 does what to the power ?

Accepted Answer

increasing alpha increases power

Question 4

in general, a distribution of t statistics is flatter & more spread out than the standard normal distribution

Accepted Answer

True

Question 5

a researcher reports a t statistic with df = 20/ how many individuals participated in the study ?

Accepted Answer

n = 21

Question 6

what is the value we don't know that makes us turn to a single sample t test from a single sample z score test ?

Accepted Answer

population standard deviation (sigma)

Question 7

under what circumstances is a type II error likely to occur ?

Accepted Answer

if the treatment effect is very small

Question 8

if other factors are held constant, are you more likely to reject the null hypothesis with a standard dev. of 2 or of 10

Accepted Answer

2 bc it will produce a smaller standard error

Question 9

what is the probability that the test will correctly reject a false null hypothesis ?

Accepted Answer

power

Question 10

changing from a one-tailed test to a two-tailed test does what to power ?

Accepted Answer

changing from one- to two-tailed decreases power

Question 11

a small value (near 0) for the z-score statistic is evidence that the sample data are consistent w the null hypothesis

Accepted Answer

True

Question 12

if a report says at the end p > .05, what is it saying about the results ?

Accepted Answer

there were no significant results, retain null

Question 13

which error occurs when the null is rejected while in fact the treatment has no effect ?

Accepted Answer

Type I Error

Questions 13