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The highlight of this week’s lab is confidence intervals and the use of these intervals in

the health sciences. There is a short reading that specifically relates confidence

intervals to health sciences and then you are asked to demonstrate your knowledge of

confidence intervals by applying them in a practical manner.

Instructions

Steps to Complete the Week 7 Lab

Step 1: Find these articles in the Chamberlain Library. Once you click each link, you will

be logged into the Library and then click on “PDF Full Text”.

• First Article: Confidence Intervals, Part 1 Links to an external site.

• Second Article: Confidence Intervals, Part 2 Links to an external site.

Step 2: Consider the use of confidence intervals in health sciences with these articles

as inspiration and insights.

Step 3: Using the data you collected for the Week 5 Lab (heights of 10 different people

that you work with plus the 10 heights provided by your instructor), discuss your

method of collection for the values that you are using in your study (systematic,

convenience, cluster, stratified, simple random). What are some faults with this type

of data collection? What other types of data collection could you have used, and how

might this have affected your study?

Step 4: Now use the Week 6 Spreadsheet to help you with calculations for the

following questions/statements.

a) Give a point estimate (mean) for the average height of all people at the place where

you work. Start by putting the 20 heights you are working with into the blue Data column

of the spreadsheet. What is your point estimate, and what does this mean?

b) Find a 95% confidence interval for the true mean height of all the people at your

place of work. What is the interval? [see screenshot below]

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c) Give a practical interpretation of the interval you found in part b, and explain carefully

what the output means. (For example, you might say, “I am 95% confident that the

true mean height of all of the people in my company is between 64 inches and

68 inches”).

d) Post a screenshot of your work from the t value Confidence Interval for µ from the

Confidence Interval tab on the Week 6 Excel spreadsheet

Step 5: Now, change your confidence level to 99% for the same data, and post a

screenshot of this table, as well.

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Step 6: Compare the margins of error from the two screenshots. Would the margin of

error be larger or smaller for the 99% CI? Explain your reasoning.

Step 7: Save the Week 7 Lab document with your answers and include your name in

the title.

Step 8: Submit the document.

Requirements

The deliverable is a Word document with your answers to the questions posed below

based on the article you find.