Reference no: EM132284144
Assignment - HYPOTHESIS II, TESTS for TWO POPULATIONS, ANOVA ANALYSIS of VARIANCE, ANALYSIS of COUNT DATA
Use the following Statistical Distribution Tables: the Standard Normal Distribution; the t Distribution Table; the Chi-Square Distribution Table; the F Distribution Table.
Part 1 - Read Chapter 7 'Hypothesis Testing' Sections 7.3, 7.4, 7.6. Section 7.8 is for your review only.
Review the instructor's prompt and audio presentations '2 SAMPLE TESTS'. Hypothesis testing for variances and standard deviations is for your review only.
Part 2 - Read Chapter 8 'Analysis of Variance' Sections 8.1, 8.2, 8.3.
Review instructor's prompt and audio presentation 'SEVERAL SAMPLE TESTS' on One Way Anova analysis of variance. Review the application done in Excel on one factor Anova and Tukey-Kramer pairs' comparison for significance 'Selenium Level in Meat' (on blackboard). Review the breeze presentation.
Part 3 - Read Chapter 12 'The Chi-Square Distribution and the Analysis of Frequencies' Sections 12.1, 12.2, 12.4, 12.5. Section 12.3 is for your review only.
Review instructor's prompt and audio presentation 'SEVERAL SAMPLE TESTS' on the tests for independence.
Do the following applications after reading the text and reviewing the instructor's prompts and breezes.
Two Independent Populations, Hypothesis Test on the Proportion (stand. normal distribution)
1. In a 'Kidney International Article', Avram et al. (A-27) reported on a study involving 529 hemodialysis patients and 326 peritoneal dialysis patients. They found that at baseline 249 subjects in the hemodialysis treatment group were diabetic while at baseline 134 of the peritoneal dialysis group were diabetic. Is there a significant difference in diabetes prevalence at baseline between the two groups of this study? Let ∝ = .05.
Paired Populations, Hypothesis Test on the Mean Difference (t distribution)
2. Ellen Davis Jones (A-15) studied the effects of reminiscence therapy for older women with depression. She studied 15 women 60 years or older residing for 3 months or longer in an assisted long term care facility. For this study, depression was measured by the Geriatric Depression Scale (GDS). Higher scores indicate more severe depression symptoms. The participants received Reminiscence Therapy for long - term care which uses family photographs, scrapbooks, and personal memorabilia to stimulate memory and conversation among group members. Pre-treatment and post-treatment depression scores are given in the following table. Can we conclude, based on these data, that subjects who participate in Reminiscence Therapy experience, on average, a decline in GDS depression scores? ∝ = .01.
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Pre-GDS:
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12
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10
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16
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2
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12
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18
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11
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16
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16
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10
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14
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21
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9
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19
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20
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Post-GDS:
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11
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10
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11
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3
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9
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13
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8
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14
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16
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10
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12
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22
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9
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16
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18
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One Way Anova Analysis of Variance (F distribution)
3. The Wall Street Journal conducted a stock picking contest in March 2001. In this experiment, three different methods were used to select stocks that were expected to perform well during the next five months. Four Wall Street professionals selected four stocks. Four randomly chosen readers of the Wall Street Journal also selected four stocks. Finally, four stocks were selected by flinging darts at a table containing a list of stocks. The returns of the selected stocks for March 20, 2001, to August 31, 2001, in percentage return, are given in the table. (Source: The Wall Street Journal, Sept. 2001)
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Experts
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Readers
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Darts
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+39.5
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-31.0
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+39.0
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-1.1
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-20.7
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+31.9
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-4.5
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-45.0
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+14.1
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-8.0
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-73.3
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+5.4
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At a level of significance α = 0.01, is there evidence of a significant difference in the average return for the three categories?
Chi Square for Independence (chi square distribution)
4. A survey concerning important issues facing the internet asked the general public and internet experts if they had a serious concern regarding the following statement: "Most web sites place a small file in your computer, called a cookie that makes it possible for internet businesses to keep track of all the web sites you have visited". The responses to the statement, cross classified by the type of user, are given in the following table. (Source: the Markle Foundation)
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SERIOUSNESS of CONCERN over STATEMENT
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TYPE of USER
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Serious
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Not Serious
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TOTAL
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General Public
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67
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28
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93
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Internet Experts
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46
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54
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100
|
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TOTAL
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113
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82
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193
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At a level of significance α = 0.05, is there evidence of a significant relationship between type of user and the seriousness of concern over the statement?
Paired Populations, Hypothesis Test on the Mean Difference (t distribution)
5. A doctor is interested in determining whether a film about exercise makes a significant difference in 10 persons' attitudes about exercise. The results of his questionnaire are shown. A higher numerical value shows a more favorable attitude toward exercise. Is there enough evidence to support the claim at level of significance 0.05, that there was a significant difference in change of attitude? Also find the 95% confidence for the mean difference.
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Before
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12
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11
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14
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9
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8
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6
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8
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5
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4
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7
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After
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13
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12
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10
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9
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8
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8
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7
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6
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5
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5
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Several Independent Populations, Homogeneity of Proportions (chi-square distribution).
6. According to a recent survey, 64% of Americans between the ages of 6 and 17 cannot pass a basic fitness test. A clinical researcher wishes to determine if the percentage of such students in different schools in his district are the same. He administers a basic fitness test to 120 students in each of four schools. The results are shown in the table. At level of significance 0.05, test the claim that the proportions who pass the test are equal.
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Southside
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West End
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East Hills
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Jefferson
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Total
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Passed
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49
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38
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46
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34
|
|
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Failed
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71
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82
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74
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86
|
|
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Total
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120
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120
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120
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120
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DATA PROJECT -
Hypothesis Testing for Two Related (Paired) Populations.
You may use a computer program of your choice.
Choose a variable that will allow the use of related samples. For example, you might wish to see if a persons' self-assurance has increased after meditation, or a person's skill has improved after a therapy, etc. Please do not choose a variable that is presented in the Learning Unit 5 materials (breeze, instructor's prompt, examples taken on lectures)
Select a sample of data (10 to 50) value pairs (e.g. before and after), and then complete the following:
a) Write a brief statement of the purpose of the study?
b) Define the population. What was the population?
c) State the hypothesis for the study.
d) Select a level of significance.
e) State how the sample was selected.
f) Show the raw data.
g) Decide which statistical test is appropriate and compute the test statistic (z or t). Why is the test appropriate?
h) Find the critical value(s).
i) Show the test with complete computation of all underlying statistics such as the difference in pairs, the standard deviation of the differences in pairs.
j) State the decision.
k) State the conclusion. Summarize the results.
l) Show the confidence interval for the analysis.
m) State the conclusion for the confidence interval and overall analysis you performed.
Attachment:- Assignment File.rar