Question 2

Login and open StatCrunch (directions).

Open your IAT sample data set in StatCrunch (directions)

We will use a 90% confidence interval to estimate the population proportion of participants born-female in our chosen IAT data set.

1. So, you are tasked with using your IAT sample to calculate a 90% confidence interval that estimates the population proportion of participants born-female in your particular IAT. But, you are missing a piece of information that would allow you to use your graphing calculator to find the confidence interval. What piece of information is missing?
2. Even though we cannot readily use our graphing calculators, StatCrunch can calculate the confidence interval for us! Use StatCrunch to find the 90% confidence interval for the population proportion of female participants in your particular IAT (directions - opens in a new tab). Highlight and copy everything in your StatCrunch output window and paste it in your response.
3. Identify the sample proportion (p^) in the StatCrunch output table. Then determine whether conditions are met for using the confidence interval to estimate the population proportion of female participants in your chosen IAT. Show your work.
4. If conditions are met, estimate the population proportion of female participants in your particular IAT, and state your conclusion in context. If conditions are not met, explain what a researcher could do so that conditions are met.
5. Based on your analysis, do you think the population of participants in your chosen IAT are representative of the U.S. population? Explain.

90% confidence interval results:

One sample proportion confidence interval: Outcomes in : Sample(Birth-Gender) Success : 2 p : Proportion of successes Method: Standard-Wald 90% confidence interval results:

Variable	Count	Total	Sample Prop.	Std. Err.	L. Limit	U. Limit
Sample(Birth-Gender)	431	600	0.71833333	0.018363485	0.68812809	0.74853858