Worth ½ point each
- Conventionally,
social researchers set α = .05.
- True
- False
- If
the null hypothesis is true, there is no difference between population
means.
- True
- False
- A
type I error is where you retain the null when the null is true
- True
- False
- As
the sample size increases, the distribution more closely approximates a normal
distribution.
- True
- False
Worth 1 point each
- Which
of the following exemplifies a research hypothesis?
- Men and women have different levels of income
- White and African Americans watch the same amount of TV.
- Senior citizens driving behaviors do not differ from those of teenagers.
- Liberals and conservatives have the same voting rates.
- When
we test hypotheses of differences between means, we:
- compare our results to that of a probability distribution.
- test to see if our obtained difference could have happened by chance.
- calculate a type of z score to locate our difference on a probability distribution.
- All of the above are correct.
- A
p-value of 0.05 is associated with a z-score of:
- 2.58
- 1.96
- 1.00
- None of the above
- When the null hypothesis is rejected:
a. it is quite likely that the difference between means is a result of sampling error.
b. the research hypothesis is proven false.
c. it is unlikely that the difference between means is a result of sampling error.
d. the population means are equal.
- If
the researcher fails to find a significant difference, when in fact one exists
in the population:
- a Type I error has been made.
- a Type II error has been made.
- the null hypothesis was correctly rejected.
- the research hypothesis was correctly accepted.
- A research study found that on average, people illegally use prescription drugs 3 times a year. We think that the population average is different than this. We collect a sample (N=8, M=1.87, SD=1.73). Use an alpha level of 0.05. What’s your research hypothesis?
- A major research study concluded that the mean number of times adolescents had engaged in vandalism in the past 12 months was 6.3 times. We think that the true population average is lower than that. We collected our own sample (N=100, M=4.2, SD=1.20). Set your alpha level to 0.01. What is the research hypothesis (H1)?
- When we retain the null hypothesis, we:
a. claim that a significant difference exists between groups.
b. have obtained a t-value greater than our critical t-value.
c. have committed a Type 1 error.
d. conclude that sampling error is responsible for any obtained difference.
