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For the following research scenarios, determine the threats to internal validity. No research design is ever perfect. For the examples below, there are some issues that the investigators would have to deal with in order to have confidence in drawing conclusions about the research.Then describe how you might realistically overcome these threats to internal validity.
Humor (3 pts)
Researchers wanted to know whether people find jokes funnier when somebody of their own sex told the jokes. They created a tape with a female joke teller presenting 15 jokes, followed by a male narrator telling 15 different jokes. Some of the jokes featured female victims, some featured male victims; the male and the female joke tellers told the same number of jokes with each kind of victim. Subjects listened to the jokes and rated them on the funniness. The results indicated that, in general, both women and men enjoyed jokes with female victims when the joke teller was a female and did not like them when the joke teller was a male.
Politics (3 pts)
A group of researchers wanted to know whether ignoring political issues and attacking a candidate personally helps or hurts a political candidate's chances of winning an election. They brought a group of students into a laboratory. Some students listened to an incumbent candidate laying out a specific plan to deal with political issues and problems should he be elected. The other participants were exposed to a challenger who spent her time talking about the personal problems of the incumbent and why the challenger would bring greater morality to political office. The participants rated the candidate regarding the likelihood that they would vote for the person whose message they had just been exposed to.
Freud (3 pts)
A researcher wanted to test Freud's notion that we have a kind of "psychic censor" that keeps potentially anxiety-arousing ideas from reaching consciousness. So he displayed for very brief durations (e.g., 1/1000 sec) a word at a time that was potentially disturbing (e.g., "orgasm") or neutral (e.g., "book") or positive (e.g., "gift") and asked the participants to say the word aloud when they recognized it. If they could not identify a word, he would present it for a slightly longer period of time. He used ten words of each type for each participant. The researcher hypothesized that if people had a psychic censor, they wold take longer to respond to the disturbing words. He compared men and women on their responses to the two types of words and found that female participants took longer to respond to the disturbing words compared to the others; male participants showed no difference across different types of words. (Note: I made up the details of this study, but research similar to this has actually been done.)
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