The conclusion listed below is based on a relationship between X and Y that is completely spurious. Do the following: (i) Define and explain what spurious relationship means? (ii) Think up a plausible variable, Z, that defines a compositional difference across the values of X. (iii) Describe how Z creates the relationship between X and Y. Students who smoke (X) earn lower grades (Y) than students who do not smoke. Conclusion: Smoking causes poor grades.

Full-time college students report spending a mean of 30 30 hours per week on academic​ activities, both inside and outside the classroom. Assume the standard deviation of time spent on academic activities is 4 4 hours. Complete parts​ (a) through​ (d) below. b. If you select a random sample of 25 25 ​full-time college​ students, there is an 83 83​% chance that the sample mean is less than how many hours per​ week?

Why is no one answering my questions?????

Suppose that there are 4 students who are independently taking a pop quiz. They started taking the pop quiz at the same time. The finishing time for the pop quiz (in mins) for student j (for j=1,2,3,4) has a uniform distribution on the interval [0,j].

Solve for the probability that...

1. exactly 1 student finishes the pop quiz in less than 1 min
2. all 4 students finish the pop quiz in less than 30 secs

You want to discover whether university makes students more or less politically engaged. You survey 60 students (32 freshmen and 28 seniors) and ask them whether or not they voted in the most recent state election. The results are shown in the table below.

Calculate the appropriate statistical test of your hypothesis, including test statistic, and degrees of freedom. State your conclusion regarding the research question.

Laura is testing to see if college students are more stressed out than the normal person is. The mean stress level of the average person is 50 with a known standard deviation of 10. Joseph is going a two-tailed test with α = .10. The null hypothesis is μ = 50. What precisely is μ the mean of?

Please choose the correct answer.

a.) The mean stress level of college students.
b.) The mean stress level of all people.
c.) The mean stress level of the 50 people in the sample.

Giving a test to a group of students, the grades and gender are summarized below

Let ππ represent the percentage of all male students who would receive a grade of C on this test. Use a 80% confidence interval to estimate p to three decimal places.

Enter your answer as a tri-linear inequality using decimals (not percents).

< p <

Giving a test to a group of students, the grades and gender are summarized below

Let ππ represent the percentage of all male students who would receive a grade of C on this test. Use a 80% confidence interval to estimate p to three decimal places.

Enter your answer as a tri-linear inequality using decimals (not percents).

< p <

Scenario 2: Create a sales promotion

Create a sales promotion you think will attract a lot of college students to your favorite fast-food restaurant. Examples of sales promotions: coupons, sampling, free product, etc.

Now think about traditional media that is accessed by this target audience (college students). Which one(s) would be most effective in communicating your sales promotion?

Least effective? Explain your reasoning and use the textbook readings to substantiate your views.

We are interested in conducting a study to determine whether a study intervention significantly improves college students’ test scores. The population’s GPA m = 2.64 and s = 0.42. We hope that intervention will improve girls’ body esteem scores by 0.25 points. We plan to recruit a sample of 36 students. We set our alpha level at .05 for two-tailed test. Determine the statistical power that this proposed study would have; report your answer as a percentage.

You wish to test if there is any relationship between marital status and number of children in the household of students in MTH 245 (Statistics I class). Let assume that our null hypothesis H0 is true.

H0:μ= there is any relationship between marital status and number of children among students in MTH 245 (Statistics I class)

You decide to reject H0.

a) Are you making a Type I error? ( Yes or No)

b) Are you making a Type II error? (Yes or No)