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Martha Johnson’s office hours are held in her office on the Blinn College Bryan Campus, and you can only attend them in-person.

At her company, Dylan wants to compare the average productivity of employees using a new generative AI tool versus those using traditional methods. They collect productivity data from two independent samples: one group using the AI tool (A) and another using traditional methods (T). She believes that those who use the AI tool will be faster to complete the assignment. The number of tasks completed in one hour is measured. What are the null and alternative hypotheses for the two-sample t-test in this scenario? 

The General Social Survey administers a survey every two years to a random sample of adults in the United States. In both 2008 and 2018, one of the questions asked was about the number of hours of TW watched per day.  The 95% confidence interval for

A researcher is conducting a study on internet use in Gainesville. He takes the map of Gainesville and randomly selects 5 small areas. He then surveys everyone in those 5 small areas.  This sampling strategy is called . . . 

An office manager wanted to know if the average expenditure on office supplies per month was more than 170 dollars. She took a random sample of 12 months. The sample average expenditure was 150 dollars.  What would be the appropriate null and alternative hypothesis?

Which of the following statements best compares the purpose  of two distributions?

For the hypothesis Ho:

In the year 2000, General Social Survey respondents were asked “How many hours did they spend on their personnel computer per week?”. The researchers were interested in seeing if married people (group 2) spent less time on their personnel computer than those who have never been married (group 1).  For this hypothesis (Ho: mu2 – mu1 = 0 vs. Ha: mu2 – mu1 < 0), the p-value was 0.0007. Interpret.   With a p-value of 0.0007, the researcher has [word1] statistically significant evidence that the [word2] mean of married who spend time on their personnel computer per week is [word3] than unmarried people.

Paloma wanted to predict sale prices for houses in Pierce County, Washington, based on house square footage and year built. She took a random sample of houses for sale in 2023.  Conduct an overall F test to determine whether these variables help predict sale price. Do not include screenshots from JMP. Include the model, parameters, hypotheses, test statistic, p-value, and conclusion. Use alpha = 0.05. Use the data set posted here:PierceCounty_Spring2023.xlsx You don’t have to show the checking of assumptions. (However, if you notice something off with assumptions, complete the problem anyway.)

Which of the following are properties of hierarchical clustering?