In this project, you are asked to use data from a Survey that Sr. Barbara conducted in her MT 120 classes to determine whether the students in the class were randomly guessing the identities of the two men in the photos. This part of the project will be a lot like several of the explorations of Chapter 1, where you are using a statistic (, and using an applet to calculate a p-value. Does the p-value support the idea that the students were guessing, or does the p-value suggest that students were doing something other than guessing?
If the students were doing something other than guessing, use the statistic ( from the data to estimate a reasonable value for the parameter (π). This part of investigation goes beyond what have been learned already in this class, and challenges to experiment a bit to find a better estimate for the true population parameter for this scenario.
Background: A study in Psychonomic Bulletin and Review (Lea, Thomas, Lamkin, and Bell, 2007) presented evidence that "people use facial prototypes when they encounter different names." Participants in that study were given photos of two faces and asked to identify which face is "Tim" and which is "Bob." Sr. Barbara is replicating this study with students in her MT 120 Applied Statistics classes. On September 26 - 27, she asked students in all three sections of MT 120 to identify from two photos, which face belongs to "Bob" and which to "Tim." Were her students simply guessing, or were they doing something other than guessing?
On September 26 and 27, Sr. Barbara gave her students an opportunity to participate in a quick survey about Tim and Bob. She asked the students to quickly identify whether the face on the left belongs to a man named Tim or to a man named Bob. Forty-two students completed this survey. The results of this survey is that 9 students said that Bob was on the left while 33 students said Tim was on the left.
1. Data Collection Methods:
To replicate the study that appeared in Psychonomic Bulletin and Review, Sister Barbara did not ask "all people" to identify the men in the photos, but rather just a sample from a larger population. You may recall that she asked you to look at photos of two men, and to identify whether the face on the left was Bob or Tim.
· How, where, and when was this data collected? Who did Sister Barbara survey?
· Who or what are the observational units, and what is the variable for each observational unit? What is the statistic?
· What does this sample (students in Sr. Barbara's MT 120 classes) suggest to us about the larger population? Did Sister Barbara take a simple random sample to collect this data? Do you think it is reasonable for her to assume that this sample is representative of some larger population?
· What is the population to which it would be reasonable to extend these results? Does it seem reasonable to extend the results of this study to all undergraduate students at Cardinal Stritch University? To the population of all students (both grads and undergrads) at Stritch? To people beyond Stritch? All people in the United States? Beyond the United States? Why?
2. Summary and Conclusions:
White a paragraph summarizing this study.
· What did you learn about students in Sr. Barbara's classes, Stritch students, or people in general? Do these results surprise you? Why?
· If the p-value suggests that Sr. Barbara's students were doing something other than simply guessing, suggest a better value for the parameter (or an interval of plausible values for the parameter). Explain how you determined a plausible value (or interval of plausible values) for the parameter. This question asks you to go beyond what you've learned (so far) in this course. Use critical thinking to identify a reasonable value (or interval of possible values) for the parameter. Explain how your are doing this.
· What do you think is going on here? Do you think the students were guessing, or is something else going on?