[MMW] Sample Test

1. B. Results of a hypothesis test

1. A company uses inferential statistics to conclude that customers prefer Product A over Product B. What justifies this conclusion?
A. The mode of satisfaction scores
B. Results of a hypothesis test
C. Graphs and charts
D. Raw survey responses

2. B. It is accepted only if the null is rejected

2. In hypothesis testing, what is the role of the alternative hypothesis?
A. It represents the status quo
B. It is accepted only if the null is rejected
C. It must always be true
D. It can never equal the population parameter

3. B. Two-tailed test

3. Suppose H₀: μ = 50 and Hₐ: μ ≠ 50. This is an example of a:
A. One-tailed test
B. Two-tailed test
C. Directional test
D. Right-tailed test

4. C. The fertilizer affects plant growth

4. In testing the effect of a new fertilizer, the null hypothesis states: “The new fertilizer has no effect on plant growth.” What would be an appropriate alternative hypothesis?
A. The fertilizer decreases plant growth
B. The fertilizer increases plant growth
C. The fertilizer affects plant growth
D. Plants grow slower with fertilizer

5. C. There is not enough evidence against it

5. What does it mean if the null hypothesis is not rejected?
A. It is proven to be true
B. It is definitely false
C. There is not enough evidence against it
D. The alternative is accepted

6. D. Range

6. A bimodal distribution will likely affect which measure the most?
A. Mean
B. Median
C. Mode
D. Range

7. C. Median

7. What is the best measure of central tendency when data has extreme outliers?
A. Mean
B. Median
C. Mode
D. Standard deviation

8. D. Reject the null hypothesis

8. A test statistic falls in the critical region. What conclusion should be made?
A. Accept the null hypothesis
B. Increase the sample size
C. Fail to reject the null hypothesis
D. Reject the null hypothesis

9. B. Accept Ha

9. A researcher uses α = 0.01 and obtains p = 0.018. What decision should they make?
A. Reject H₀
B. Accept Hₐ
C. Fail to reject H₀
D. Lower the alpha level

10. A. Categorical

10. A chi-square test is used for which type of variable?
A. Categorical
B. Ratio
C. Continuous
D. Interval

11. C. Simple linear regression

11. What statistical method is used when predicting a numerical outcome based on one independent variable?
A. ANOVA
B. Correlation
C. Simple linear regression
D. Logistic regression

12. C. One-sample t-test

12. Which test compares the mean of a single sample to a known population mean?
A. Independent t-test
B. Z-test
C. One-sample t-test
D. Paired t-test

13. C. Normal distribution of data

13. A t-test assumes which of the following?
A. Large sample size
B. Known population variance
C. Normal distribution of data
D. Ordinal data

14. B. One dataset is more spread out

14. Two datasets have the same mean but different standard deviations. What does this imply?
A. They are identical
B. One dataset is more spread out
C. They have different medians
D. One has fewer values

15. D. Standard deviation

15. Which of the following is most influenced by every data value in a dataset?
A. Range
B. Median
C. Interquartile range
D. Standard deviation

16. A. Type I error

16. A doctor wrongly concludes that a patient has a disease when they actually do not. This is an example of:
A. Type I error
B. Type II error
C. Correct rejection
D. Power of the test

17. B. Decrease risk of Type I error

17. Reducing the significance level from 0.05 to 0.01 will:
A. Increase power
B. Decrease risk of Type I error
C. Decrease risk of Type II error
D. Increase sample variability

18. C. You are showing change over time

18. A line graph is most appropriate when:
A. You want to compare parts of a whole
B. You are showing frequency of categories
C. You are showing change over time
D. You are displaying proportions

19. D. Scatterplot

19. Which graph is most appropriate to display the relationship between two continuous variables?
A. Boxplot
B. Pie chart
C. Histogram
D. Scatterplot

20. D. Negative correlation

20. A scatterplot shows a downward trend from left to right. What does this indicate about the correlation?
A. Strong positive correlation
B. No correlation
C. Weak correlation
D. Negative correlation

21. B. When comparing two means from two different groups

21. When is an independent t-test appropriate to use?
A. When comparing scores before and after an intervention in the same group
B. When comparing two means from two different groups
C. When assessing the correlation between two variables
D. When measuring variance in a dataset

22. Independent t-test

22. A study compares test scores between two different classes. Which test should be used?
A. Paired t-test
B. ANOVA
C. Independent t-test
D. Chi-square test

23. A. Observations are matched or paired

23. What is a key assumption of the independent t-test?
A. Observations are matched or paired
B. Data are ordinal
C. Independent groups and normally distributed
D. The variables are categorical

24. Comparing matched pairs before and after a treatment

24. A paired t-test is most appropriate when:
A. Analyzing categorical data
B. Comparing matched pairs before and after a treatment
C. Testing for association between two variables
D. Testing independent groups

25. A. Paired t-test

25. A researcher tests blood pressure before and after medication in the same group of patients. What statistical test is appropriate?
A. Paired t-test
B. Independent t-test
C. One-way ANOVA
D. Chi-square test

26. C. Differences between paired values

26. In a paired t-test, the analysis is based on:
A. Difference of group means
B. Sum of individual scores
C. Differences between paired values
D. Frequency counts

27. C. Strong negative relationship

27. What does a correlation coefficient (r) of -0.85 imply?
A. No relationship
B. Weak positive relationship
C. Strong negative relationship
D. Moderate positive relationship

28. C. Negative correlation

28. A researcher finds that as stress levels increase, productivity decreases. What kind of correlation exists?
A. No correlation
B. Positive correlation
C. Negative correlation
D. Causal correlation

29. B. r = -0.95

29. Which of the following values indicates the strongest linear correlation?
A. r = 0.20
B. r = -0.95
C. r = 0.70
D. r = -0.40

30. C. Pearson correlation

30. Which statistical tool is appropriate when measuring the strength and direction of a relationship between two quantitative variables?
A. T-test
B. ANOVA
C. Pearson correlation
D. Chi-square test