Q. What is the relationship between Computer Attitudes scores and Computer Self Efficacy scores of students? (50 pts.)

a) Hypothesis testing (15pts.)

b) Evaluate the Scatterplot (15pts.)

c) Results and Interpretation (20pts.)

Data: (if needed)

Race   Position   Oral exam results   Written exam results   Combined results
B   Lieutenant   45.83   46   45.932
B   Lieutenant   52.92   49   50.568
B   Captain   54.76   49   51.304
H   Lieutenant   48.33   58   54.132
B   Lieutenant   52.08   56   54.432
H   Lieutenant   40.83   64   54.732
B   Captain   60   53   55.8
W   Captain   53.81   58   56.324
B   Lieutenant   58.75   55   56.5
W   Lieutenant   54.58   58   56.632
B   Lieutenant   55.83   58   57.132
W   Lieutenant   45.42   65   57.168
H   Lieutenant   44.17   66   57.268
H   Captain   42.86   67   57.344
W   Lieutenant   44.58   66   57.432
W   Lieutenant   51.25   62   57.7
W   Lieutenant   57.92   58   57.968
B   Captain   70.48   50   58.192
B   Lieutenant   60.83   58   59.132
H   Lieutenant   46.25   68   59.3
H   Captain   57.14   61   59.456
W   Lieutenant   60   60   60
W   Lieutenant   49.58   67   60.032
B   Lieutenant   51.25   66   60.1
B   Lieutenant   55   64   60.4
B   Captain   67.62   56   60.648
H   Lieutenant   51.25   67   60.7
H   Lieutenant   42.5   73   60.8
W   Captain   48.57   69   60.828
B   Lieutenant   56.25   64   60.9
B   Lieutenant   56.67   64   61.068
W   Lieutenant   56.25   66   62.1
H   Captain   58.57   65   62.428
H   Lieutenant   50.42   71   62.768
W   Lieutenant   71.67   57   62.868
W   Captain   55.24   68   62.896
H   Lieutenant   51.67   71   63.268
B   Lieutenant   69.17   60   63.668
H   Lieutenant   57.5   70   65
W   Lieutenant   50.42   75   65.168
B   Lieutenant   66.25   65   65.5
W   Lieutenant   55   73   65.8
H   Captain   67.14   65   65.856
H   Lieutenant   56.25   73   66.3
W   Lieutenant   79.17   59   67.068
B   Captain   52.38   77   67.152
W   Lieutenant   64.58   69   67.232
B   Lieutenant   70.83   65   67.332
W   Captain   57.14   75   67.856
W   Lieutenant   51.67   79   68.068
H   Lieutenant   62.5   72   68.2
W   Lieutenant   51.25   80   68.5
W   Lieutenant   73.75   66   69.1
W   Lieutenant   58.75   76   69.1
H   Lieutenant   70.83   68   69.132
H   Captain   60.48   75   69.192
W   Captain   59.05   76   69.22
W   Captain   71.43   68   69.372
W   Captain   71.43   68   69.372
W   Lieutenant   64.58   73   69.632
W   Captain   78.57   64   69.828
W   Captain   62.38   75   69.952
W   Lieutenant   71.67   69   70.068
W   Lieutenant   73.75   68   70.3
B   Captain   70.95   70   70.38
W   Lieutenant   77.5   66   70.6
H   Lieutenant   53.75   82   70.7
W   Lieutenant   65.83   74   70.732
W   Lieutenant   58.33   79   70.732
H   Lieutenant   69.17   72   70.868
H   Lieutenant   55   82   71.2
W   Captain   56.67   81   71.268
W   Captain   82.38   64   71.352
B   Captain   68.57   74   71.828
W   Lieutenant   73.33   71   71.932
W   Lieutenant   72.5   72   72.2
B   Lieutenant   92.08   59   72.232
W   Lieutenant   66.67   76   72.268
B   Lieutenant   70.83   74   72.732
W   Lieutenant   78.33   70   73.332
W   Captain   70   76   73.6
W   Captain   73.33   74   73.732
B   Lieutenant   65.83   80   74.332
W   Lieutenant   87.5   66   74.6
B   Captain   82.38   70   74.952
W   Captain   76.67   74   75.068
W   Lieutenant   63.33   83   75.132
W   Captain   73.81   77   75.724
W   Lieutenant   74.17   77   75.868
B   Lieutenant   80.42   73   75.968
H   Captain   79.05   74   76.02
B   Lieutenant   61.25   86   76.1
W   Captain   80   74   76.4
W   Captain   87.62   69   76.448
B   Lieutenant   77.5   76   76.6
W   Lieutenant   58.75   89   76.9
W   Captain   84.29   72   76.916
W   Lieutenant   73.75   81   78.1
W   Captain   73.81   81   78.124
H   Captain   70   84   78.4
W   Lieutenant   69.58   86   79.432
W   Captain   76.19   82   79.676
H   Captain   76.19   82   79.676
W   Captain   76.19   84   80.876
W   Captain   88.57   76   81.028
W   Lieutenant   68.33   91   81.932
W   Lieutenant   63.75   95   82.5
W   Lieutenant   80.83   84   82.732
W   Lieutenant   73.33   89   82.732
W   Lieutenant   73.75   91   84.1
W   Lieutenant   80   87   84.2
W   Lieutenant   85   84   84.4
W   Captain   82.38   87   85.152
W   Lieutenant   77.5   91   85.6
W   Lieutenant   87.5   87   87.2
W   Captain   80   95   89
W   Lieutenant   88.75   91   90.1
W   Captain   89.52   95   92.808

Test whether the combined test scores for the Lieutenant exam are the same for all the three races at the 5% significance level.

Test statistic, F: 8.58, 12.09, 6.84, or 8.01? (select one)

P-value: 0.004, 0.963, 0.084, or 0.027? (select one)

Conclusion: A. Reject the null hypothesis. There is sufficient evidence that at least one mean combined score is different between races.

B. Reject the null hypothesis. There is insufficient evidence that at least one mean combined score is different between races.

C. Fail to reject the null hypothesis. There is sufficient evidence that at least one mean combined score is different between races.

D. Fail to reject the null hypothesis. There is insufficient evidence that at least one mean combined score is different between races.

Standart represantation of Galois Field (27)

The basic materials stock sector, comprised of companies specializing in industrial commodities, had a very poor showing during the first six months of 2000. The average stock price in this sector was down an average of 27% for this period. Assume that the returns were distributed as a normal random variable with a mean of -27% and a standard deviation of 15%.

1. [3] If an individual stock were selected from this population, what is the probability that it would have a return of between -37 and -17%?

2. [3] If an individual stock were selected from this population, what is the probability that it would have made a profit – i.e. a return greater than 0.0%?

3. [3] If random samples, of 10 stocks were selected from this population. What proportion of the samples would have a mean return of between -37% and -17%?

4. [3] If random sample of 10 stocks were selected from this population, what proportion of the samples would have made a profit?

Twenty-five students from Harry High School were accepted at Magic University. Of those students, 10 were offered athletic scholarships and 15 were not. Mrs. Hermione believes Magic University may be accepting people with lower ACT scores if they are athletes. The newly accepted student ACT scores are shown here. Athletic scholarship: 16, 24, 20, 25, 24, 23, 21, 22, 20, 20 No athletic scholarship: 23, 25, 26, 30, 32, 26, 28, 29, 26, 27, 29, 27, 22, 24, 25 Part A: Do these data provide convincing evidence of a difference in ACT scores between athletes and nonathletes? Carry out an appropriate test at the α = 0.10 significance level. (5 points) Part B: Create and interpret a 90% confidence interval for the difference in ACT scores between athletes and nonathletes. (5 points)

The data in the table below gives sales revenue for Continental Divide Mining from 1995 to 2005.

YEAR YEARS SINCE 1990 SALES REVENUE (MILLIONS)
1995 2.6155
1998 3.3131
1999 3.9769
2000 4.5494
2001 4.8949
2002 5.1686
2003 4.9593
2005 4.7489

(a) Complete the missing column in the table.
(b) Use Excel to determine the quadratic regression model, y, that best represents sales revenue as a
function of, x, the number of years since 1990. Round three decimal places.

(a) Find the year in which there is maximum revenue and find the maximum revenue. Write solution as a
complete sentence.

Fantastic Styling Salon is run by three stylists, Jenny Perez, Jill Sloan, and Jerry Tiller, each capable of serving four customers per hour, on average. Use POM for Windows or OM Explorer to answer the following questions: During busy periods of the day, when nine customers on average arrive per hour, all three stylists are on staff.

a. If all customers wait in a common line for the next available stylist, how long would a customer wait in line, on average, before being served?

b. Suppose that each customer wants to be served by a specific stylist, 1/3 want Perez, 1/3 want Sloan, 1/3 want Tiller. How long would a customer wait in line, on average, before being served? During less busy periods of the day, when six customers on average arrive per hour, only Perez and Sloan are on staff.

c. If all customers wait in a common line for the next available stylist, how long would a customer wait in line, on average, before being served?

d. Suppose that each customer wants to be served by a specific stylist, 60 percent want Perez and 40 percent want Sloan. How long would a customer wait in line, on average, before being served by Perez? By Sloan? Overall?

The mean amount purchased by each customer at Churchill’s Grocery Store is $27 with a standard deviation of $9. The population is positively skewed. For a sample of 48 customers, answer the following questions:

a. What is the likelihood the sample mean is at least $29? (Round the z-value to 2 decimal places and the final answer to 4 decimal places.)

b. What is the likelihood the sample mean is greater than $26 but less than $29? (Round the z-value to 2 decimal places and the final answer to 4 decimal places.) c. Within what limits will 98% of the sample means occur? (Round the final answers to 2 decimal places.)

A telephone service representative believes that the proportion of customers completely satisfied with their local telephone service is different between the Midwest and the South. The representative's belief is based on the results of a survey. The survey included a random sample of 1120 midwestern residents and 1260 southern residents. 37% of the midwestern residents and 49% of the southern residents reported that they were completely satisfied with their local telephone service. Find the 80%

confidence interval for the difference in two proportions.

Step 1 of 3 :

Find the point estimate that should be used in constructing the confidence interval.

Step 2 of 3: Find the margin of error. Round your answer to six decimal places. Step 3 of 3: Construct the 80% confidence interval. Round your answers to three decimal places.

A telephone service representative believes that the proportion of customers completely satisfied with their local telephone service is different between the Midwest and the West. The representative's belief is based on the results of a survey. The survey included a random sample of 760 midwestern residents and 680 western residents. 37% of the midwestern residents and 46% of the western residents reported that they were completely satisfied with their local telephone service. Find the 90% confidence interval for the difference in two proportions.

Step 1 of 3 :  

Find the point estimate that should be used in constructing the confidence interval.

Step 2 of 3:

Find the margin of error. Round your answer to six decimal places.

Step 3 of 3:

Construct the 90% confidence interval. Round your answers to three decimal places.