Week 5 Project – STAT 3001
Student Name: <Type your name here>
Date: <Enter
the date on which you began working on this assignment.>
This assignment is worth a total of 60
points.
Part
I. Chi-Square Goodness of Fit Test
(equal frequencies)
In order to determine staffing levels, a
hospital wants to determine if births occur with the same frequency on each day
of the week. The table below lists the
days of the week selected by a random sample of 100 births. Consider the claim
that the days of the week have the same frequency of a birth occurring.
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Sunday |
Monday |
Tuesday |
Wednesday |
Thursday |
Friday |
Saturday |
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32 |
16 |
7 |
20 |
11 |
8 |
6 |
Instructions for performing this test in
Stat Disk can be found in the Stat Disk User’s Manual under Goodness of Fit,
Equal Frequencies.
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Instructions |
Answers |
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1. Paste |
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2. |
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3. |
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4. |
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5. |
Part
II. Chi-Square Goodness of Fit Test
(unequal frequencies)
In the 2000 U.S. Census, the ages of
individuals in a small town were found to be the following:
Less than 18 – 20% 18-35 – 30% and
greater than 35 – 50%
In 2010 the ages of 500 individuals from
the same small town were sampled with the following results:
Less than 18 – 121 people 18-35 – 288 people and greater than 35 – 91 people
Using an alpha of 0.05, would you
conclude that the population distribution of ages has changed in the last 10
years? Instructions for performing this
test in Stat Disk can be found in the Stat Disk User’s Manual under Goodness of
Fit, Unequal Frequencies.
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Instructions |
Answers |
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6. [Hint: |
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Less than 18 |
18-35 |
35-91 |
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OBSERVED |
121 |
288 |
91 |
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EXPECTED |
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7. Paste |
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8. |
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9. |
Part
III. Chi-Square Test of Independence
The following table is the result of a
survey from a random sample of different crime victims.
Use the data to test the claim that the
type of crime is independent of whether the criminal was a stranger. Use a significance level of 0.05.
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Homicide |
Robbery |
Assault |
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Criminal was a stranger |
12 |
379 |
727 |
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Criminal was an acquaintance or relative |
39 |
106 |
642 |
Hint: Instructions for performing this
test in Stat Disk can be found in the Stat Disk User’s Manual under the heading
Chi Square Test of Independence (Contingency Tables).
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Instructions |
Answers |
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10. Just looking at the numbers in the table, what is your best guess |
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11. Compute a Chi-Square Test of Independence on this data using a 0.05 level of significance. Paste your results here. |
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12. What are the null and alternative hypothesis for this test? |
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13. What is the p-value for this result? What does this represent? |
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14. State your conclusion related to the context of this problem. |
Part
IV. Apply this to your own situation
Using one of the above statistical
tests, compose and SOLVE an actual problem from the
context of your own personal or professional life. You will need to make up some data and
describe which test you will use to analyze the situation. Here’s an example:
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Example:Do not use this problem!! |
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State the problem that you are |
Last year, I asked the kids in my |
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Make up some data for the new |
I asked 50 neighborhood kids what kind · · · |
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Determine which type of Chi-Square |
Since these are unequal frequencies, I |
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Specify your null and alternative |
H0: H1: |
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Setup the test |
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Chocolate-Chip |
Oatmeal-Raisin |
Sugar-Cookie |
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OBSERVED |
35 |
5 |
10 |
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EXPECTED |
25 |
10 |
15 |
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Perform the test |
Paste your STATDISK results here |
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State your conclusion |
We have evidence to believe …. |
Submit your final draft of your Word file
by going to Week 5, Project, and follow the directions under Week 5 Assignment
2. Please use the naming convention “WK5Assgn2+first initial+last
name” as the Submission Title.

