Question

A researcher predicts that showing a certain film will change people's attitudes toward alcohol. The researchers then randomly select 36 people, show them the film, and give them an attitude questionnaire. The mean score on the attitude questionnaire for this sample of people is 70 . In the general population, the average score for people on this test is 75 , with a standard deviation of 12 (assume the alpha level = .05). a. Identify the independent variable. b. Identify the dependent variable. c. In a sentence, state the null hypothesis. d. Using symbols, state the null hypothesis. e. Using symbols, state the alternative hypothesis. f. Conduct the hypothesis test using a two- tailed test with alpha =.05. g. What is your conclusion regarding the null hypothesis? Should you reject or fail to reject the null hypothesis? h. What can you conclude about the film and attitudes toward alcohol based on your hypothesis test results?

Answer 1

The hypothesis test results suggest that there is not enough evidence to reject the null hypothesis. Therefore, the film did not significantly change people's attitudes toward alcohol.

Step-by-step explanation:

In this study, the independent variable is the film shown to participants, and the dependent variable is the score on the attitude questionnaire. The null hypothesis (H0) posits that there is no significant difference in attitudes toward alcohol after watching the film, implying that the mean score remains the same as in the general population. Symbolically, H0: μ = 75, where μ represents the population mean.

The alternative hypothesis (H1) proposes a significant change in attitudes, suggesting that the mean score is not equal to 75. Symbolically, H1: μ ≠ 75. To test these hypotheses, a two-tailed t-test with an alpha level of 0.05 is conducted. The calculated t-statistic is then compared to the critical t-value.

The conclusion from the hypothesis test is based on whether the calculated t-statistic falls within the critical region. If the t-statistic falls within the critical region, the null hypothesis is rejected. However, if it falls outside the critical region, there is insufficient evidence to reject the null hypothesis.

In this case, as the results do not provide enough evidence to reject the null hypothesis, we conclude that the film did not significantly change people's attitudes toward alcohol. It is essential to interpret these findings cautiously, considering factors like sample size and the potential for Type II errors in hypothesis testing.