Chapter 16

Question 1

Null hypothesis

Answer 1

Statement that provides an explanation is not valid

- Invalid – not true

Question 2

Alternative hypothesis

Answer 2

Another possibility to the null hypothesis – statement that provides an explanation is valid
- Available as another possibility

Question 3

Directional hypothesis

Answer 3

An alternative hypothesis that includes a “less than sign” ()
- Provides a direction to the comparison

Question 4

Nondirectional hypothesis

Answer 4

A statement that does not specify the orientation (direction) of the difference
- E.g., there is a different in scores obtained on a math test between males and females

Question 5

Level of significance (alpha level)

Answer 5

The probability of obtaining a sample that supporting the hypothesis is so small that it becomes important, worthy of attention

• Another name for alpha level
• Alpha level: the point at which one would reject the null hypothesis and accept the alternative hypothesis

Question 6

Probability value (p-value)

Answer 6

The likelihood of the observed value (or a more extreme value) of a statistic, if the null hypothesis were true
- P-value: a shorter name for probability value in significance testing

Question 7

Critical region

Answer 7

The area on a null hypothesis sampling distribution where the observed value of the statistic, if it fell in this area, would be considered a rare event

Question 8

Statistical power

Answer 8

The probability of correctly rejecting the null hypothesis when it is false

Question 9

Type I error

Answer 9

Rejection of a true null hypothesis

Question 10

Type II

Answer 10

Failure to reject a false null hypothesis