Part 1) STATISTICS AT WORK (4 pts)

Having statistical knowledge at work can have advantages, even if you aren't a statistical analyst yourself.Without this knowledge, interpreting and understanding many business studies can be difficult or worse, dangerous, because you can't evaluate the results yourself, and must trust those presenting results to you.When you are able to share this knowledge with colleagues, it can help them and your company make better decisions.

Suppose you and several coworkers recently attended a presentation where some statistical results of

an important study were shown.How would you respond to the situations below?

(Write a meaningful paragraph for each question.)

1.Halfway through the presentation there is a break.During the break, your boss comes over and mentions she noticed they were using -tests throughout the presentation, but she isn't sure that was the right choice.Using your own words, explain the differences between a -test and a -test.

2.A junior-level teammate noticed your comments to your boss and shortly after the presentation he stops by your desk to ask a couple questions.In your own words, explain to him what hypothesis testing is, how it can be useful, and the general steps of running a hypothesis test.

3.That same associate also asks if you could explain what 'statistical significance' is and how you determine if a difference is big enough to be significant.

4.Later that evening you are reflecting on your day, and you remain concerned that some of the data presented relied on very low sample sizes, and you believe the presenters showed results that were less reliable than they claimed.Who would you talk about this at work, and what would you say?

Part 2) CHARITABLE GIVING (6 pts)

You have set a professional goal to become the lead of your city's annual Charitable Giving Campaign.The mayor has agreed to give you that role if you can inspire your team to create enough workplace goodwill that more than 60% of employees around the city increase their level of participation in the campaign this year.A random sample of post-campaign data shows that 34 of 47 employees have upped their giving this year, and you think the new title is yours.However, the next day the mayor comes up to you and says she thinks it could have been random chance that so many employees participated in the campaign this year.Show her you deserve to head up the campaign by proving her wrong! (Use = 0.05.)

1.What is the name of the type of hypothesis test required here?

Is this a left-tailed, right-tailed, or two-tailed test?

2.State AND verify all assumptions required for this test.

[HINT: this test should have four assumptions to be verified.]

3.State the null and alternate hypotheses for this test: (use correct symbols and format!)

Null hypothesis

Alternate hypothesis

4.Run the correct hypothesis test and provide the information below.Give the correct symbol AND numeric value of each of the following (round answers to 3 decimal places).

Test Statistic

Critical value [HINT: this is NOT ]

p-value

5.State your statistical decision (and justify it!)

6.Interpret your decision within the context of the problem: what is your conclusion?

Part 3) URGENT CARE (6 pts)

You recently started working as a nurse manager at a larger local urgent care facility.Because the center is so new (and a bit fancier than most) many patients come here expecting a bit of a wait before they can be seen.Out of curiosity, on a particularly busy day you write down how many minutes a random sample of patients has to wait before being seen by one of the medical staff.Using a significance level of 20%, test whether the average wait time is less than 15 minutes.

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1.What is the name of the type of hypothesis test required here?

Is this a left-tailed, right-tailed, or two-tailed test?

2.State AND verify all assumptions required for this test.

[HINT: this test has two assumptions.]

3.State the null and alternate hypotheses for this test: (use correct symbols and format!)

Null hypothesis

Alternate hypothesis

4.Run the correct test in Excel or on the TI-84 calculator and provide the information below.For each statistic provide the correct symbol and numeric value (round answers to 3 decimal places).

Degrees of Freedom

Test Statistic

Critical Value

p-value

5.State your statistical decision for this test and justify it using the statistics above.

6.Interpret your decision within the context of the problem: what is your conclusion?