Brilliant answer 2 | StudyDaddy.com

Time to Practice – Week Five

Complete Parts A, B, and C below.

Part A

Some questions in Part A require that you access data from Statistics for People Who (Think They) Hate Statistics. This data is available on the student website under the Student Text Resources link.

1.     Use the following data to answer Questions 1a and 1b.

Total no. of problems correct (out of a possible 20)

Attitude toward test taking (out of a possible 100)

17

94

13

73

12

59

15

80

16

93

14

85

16

66

16

79

18

77

19

91

a.     Compute the Pearson product-moment correlation coefficient by hand and show all your work.

b.     Construct a scatterplot for these 10 values by hand. Based on the scatterplot, would you predict the correlation to be direct or indirect? Why?

2.     Rank the following correlation coefficients on strength of their relationship (list the weakest first):

+.71

+.36

–.45

.47

–.62

3.     Use IBM® SPSS® software to determine the correlation between hours of studying and grade point average for these honor students. Why is the correlation so low?

Hours of studying

GPA

23

3.95

12

3.90

15

4.00

14

3.76

16

3.97

21

3.89

14

3.66

11

3.91

18

3.80

9

3.89

4.     Look at the following table. What type of correlation coefficient would you use to examine the relationship between sex (defined as male or female) and political affiliation?

How about family configuration (two-parent or single-parent) and high school GPA? Explain why you selected the answers you did.

Level of Measurement and Examples

Variable X

Variable Y

Type of correlation

Correlation being computed

Nominal (voting preference, such as Republican or Democrat)

Nominal (gender, such as male or female)

Phi coefficient

The correlation between voting preference and gender

Nominal (social class, such as high, medium, or low)

Ordinal (rank in high school graduating class)

Rank biserial coefficient

The correlation between social class and rank in high school

Nominal (family configuration, such as intact or single parent)

Interval (grade point average)

Point biserial

The correlation between family configuration and grade point average

Ordinal (height converted to rank)

Ordinal (weight converted to rank)

Spearman rank correlation coefficient

The correlation between height and weight

Interval (number of problems solved)

Interval (age in years)

Pearson product-moment correlation coefficient

The correlation between number of problems solved and the age in years

5.     When two variables are correlated (such as strength and running speed), it also means that they are associated with one another. But if they are associated with one another, then why does one not cause the other?

6.     Given the following information, use Table B.4 in Appendix B of Statistics for People Who (Think They) Hate Statistics to determine whether the correlations are significant and how you would interpret the results.

a.     The correlation between speed and strength for 20 women is .567. Test these results at the .01 level using a one-tailed test.

b.     The correlation between the number correct on a math test and the time it takes to complete the test is –.45. Test whether this correlation is significant for 80 children at the .05 level of significance. Choose either a one- or a two-tailed test and justify your choice.

c.     The correlation between number of friends and grade point average (GPA) for 50 adolescents is .37. Is this significant at the .05 level for a two-tailed test?

7.     Use the data in Ch. 15 Data Set 3 to answer the questions below. Do this one manually or use IBM® SPSS® software.

a.     Compute the correlation between income and level of education.

b.     Test for the significance of the correlation.

c.     What argument can you make to support the conclusion that lower levels of education cause low income?

8.     Use the following data set to answer the questions. Do this one manually.

a.     Compute the correlation between age in months and number of words known.

b.     Test for the significance of the correlation at the .05 level of significance.

c.     Recall what you learned in Ch. 5 of Salkind (2014)about correlation coefficients and interpret this correlation.

Age in months

Number of words known

12

6

15

8

9

4

7

5

18

14

24

18

15

7

16

6

21

12

15

17

9.     How does linear regression differ from analysis of variance?

10.  Betsy is interested in predicting how many 75-year-olds will develop Alzheimer’s disease and is using level of education and general physical health graded on a scale from 1 to 10 as predictors. But she is interested in using other predictor variables as well. Answer the following questions.

a.     What criteria should she use in the selection of other predictors? Why?

b.     Name two other predictors that you think might be related to the development of Alzheimer’s disease.

c.     With the four predictor variables (level of education, general physical health, and the two new ones that you name), draw out what the model of the regression equation would look like. 







Calculate Your Essay Price
(550 words)

Approximate price: $22

Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
$26
The price is based on these factors:
Academic level
Number of pages
Urgency
Basic features
  • Free title page and bibliography
  • Unlimited revisions
  • Plagiarism-free guarantee
  • Money-back guarantee
  • 24/7 support
On-demand options
  • Writer’s samples
  • Part-by-part delivery
  • Overnight delivery
  • Copies of used sources
  • Expert Proofreading
Paper format
  • 275 words per page
  • 12 pt Arial/Times New Roman
  • Double line spacing
  • Any citation style (APA, MLA, Chicago/Turabian, Harvard)

Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

Read more

Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

Read more

Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.

Read more

Privacy policy

Your email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.

Read more

Fair-cooperation guarantee

By sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.

Read more

Order your essay today and save 10% with the coupon code: best10