introduction to hypothesis testing

Question 1

hypothesis testing

Answer 1

an inferential procedure that uses sample data to evaluate the credibility of a hypothesis about a given population

Question 2

steps in hypothesis testing

Answer 2

(1) stating the hypothesis, (2) setting the criteria for a decision, (3) collecting sample data, (4) evaluating the null hypothesis

Question 3

null hypothesis (Hv0)

Answer 3

predicts that the independent variable will have no effect on the dependent variable for the population

Question 4

alternative hypothesis (Hv1)

Answer 4

predicts that the independent variable will have an effect on the dependent variable for the population

Question 5

Type I error

Answer 5

rejecting the null hypothesis when it is actually true

Question 6

Type II error

Answer 6

failing to reject the null hypothesis when it is actually false

Question 7

level of significance (alpha level)

Answer 7

a probability value used to define the term “very unlikely”; whenever an experiment produces very unlikely data as determined by the alpha level, we the experimenters will reject the null hypothesis; the alpha level thus also defines the probability of a Type I error

Question 8

critical region

Answer 8

an area composed of extreme sample values that are very unlikely to be obtained if the null hypothesis is true; sample data that fall within the critical region will warrant the rejection of the null hypothesis

Question 9

directional hypothesis test (one-tailed test)

Answer 9

a test in which the statistical hypotheses (Hv0 and Hv1) specify either an increase or a decrease in the population mean score

Question 10

statistical power

Answer 10

the probability that a test will correctly reject the null hypothesis (1 - β)

Question 11

probability of a Type II error

Answer 11

β