Chapter 5 5. There is an advantage to stating the hypothesis both in the null and the alternate; it adds clarity to our thinking about what we are testing. Explain. The null hypothesis is set so that the alternate hypothesis becomes testable. When the observed Z value is greater than or equal to the critical Z value for a given confidence level (usually 95 percent), then we know that we ought to accept the alternate hypothesis. If, however, the critical Z value is more than the observed Z value for a given level of confidence, we would be inclined not to reject the null but to reject the alternate. Setting up the null thus helps us to understand that though the null hypothesis itself is not testable, it helps to decide whether we should accept or reject the alternate. 6. Develop a conceptual model for the scenario below.
Incidence of smoking in movies has started to increase again, after having declined for several decades. According to the National Cancer Institute smoking is seen in at least three out of four contemporary boxoffice hits. What’s more, identifiable cigarette brands appeared in about one-third of all movies in 2008. Exposure to smoking in movies is an important predictor of adolescent smoking initiation: smoking in movies has been shown to affect adolescents’ intentions to start smoking. In turn, the intentions to start smoking are determined by a more positive attitude toward smoking after seeing a film character smoke. Recent research has revealed that the relationship between seeing a film character smoke and the attitude toward smoking is stronger when a person’s identification with a film character increases. These findings are consistent with social learning theory, which predicts that attitudes and behaviors are modeled by observing the behaviors of others.
