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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.