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leroywash1
May 24, 2007, 01:19 PM
I need help with the following 2 excersises. Using the 5 steps of hypothesis testing and I need to show all calculations,

Use the five-step procedure for hypothesis testing in the following exercises

12. The National Safety Council reported that 52 per cent of American turnpike drivers are men. A sample of 300 cars traveling outbound on the New Jersey Turnpike yesterday revealed that 170 were driven by men. At the .01 significance level, can we conclude that a larger proportion of men were driving on the New Jersey Turnpike than the national statistics indicate?

17. Ms. Lisa Morin is the budget director for Nexus Media, Inc. She would like to compare the daily travel expense for the sales staff and the audit staff. She collected the following sample information.

Audit (\$) 131 135 146 165 136 142

Sales (\$) 130 102 129 143 149 120 129

At the .10 significance level, can she conclude that the mean daily expenses are greater for the sales staff than the audit staff? What is the p-value?

Five-Step Procedure for Hypothesis Testing

1. Establish the hull hypothesis (H0) and the alternate hypothesis (H1).
2. Select the level of significance.
3. Select an appropriate test statistic.
4. Formulate a decision rule based on steps 1, 2, and 3 above.
5. Make a decision regarding the null hypothesis based on the sample information. Interpret the results of the test.

Clough
May 25, 2007, 02:59 AM
Please see the following site first.

leroywash1
Jun 3, 2007, 09:44 PM
I have another stastics problem I need help with and I need it ASAP!! Here is the problems and the instructions are included.

Given the following sample information, test the hypothesis that the statement means are equal at the .05 significance level.

Treatment 1 Treatment 2 Treatment 3
8 3 3
11 2 4
10 1 5
3 4
2
a. State the null and the alternate hypothesis.
b. What is the decision rule?
c. Compute the SST, SSE, and SS total.
d. Complete and ANOVA table.
e. State your decision regarding the null hypothesis.
f. If H0 is rejected, can we conclude that treatment 1 and treatment 2 differ? Use the 95 percent level of confidence.

leroywash1
Jun 3, 2007, 09:47 PM
Given the following sample information, test the hypothesis that the statement means are equal at the .05 significance level.

Treatment 1 Treatment 2 Treatment 3
8 3 3
11 2 4
10 1 5
3 4
2
a. State the null and the alternate hypothesis.
b. What is the decision rule?
c. Compute the SST, SSE, and SS total.
d. Complete and ANOVA table.
e. State your decision regarding the null hypothesis.
f. If H0 is rejected, can we conclude that treatment 1 and treatment 2 differ? Use the 95 percent level of confidence.

Clough
Jun 4, 2007, 01:13 AM
Hey, Leroy!

Did you even bother to read the information on the link that I provided?

If not, it states the following. It is part of the rules for using this site. It would be best for you to abide by them.

Read this first: Expectations for the Homework Help board

--------------------------------------------------------------------------------

"Do not simply retype or paste a question from your book or study material

We won't do your homework questions for you.
You were given the assignment for you to learn.

If you come up with your own answer and post it for us to critique that is within reason.

If you have some SPECIFIC questions that you couldn't find or didn't understand, we may help with that.
But this is your assignment, so show us you have at least attempted to complete it on your own.

Thank you."

The problem is by the way that you have posted your questions. You need to show that you have made an attempt at answering them yourself first. Then, people will be likely to help you on this site.

ton_ty2275
Jun 28, 2007, 03:10 PM
I need help with the following 2 excersises. using the 5 steps of hypothesis testing and I need to show all calculations,

Use the five-step procedure for hypothesis testing in the following exercises

12. The National Safety Council reported that 52 per cent of American turnpike drivers are men. A sample of 300 cars traveling outbound on the New Jersey Turnpike yesterday revealed that 170 were driven by men. At the .01 significance level, can we conclude that a larger proportion of men were driving on the New Jersey Turnpike than the national statistics indicate?

17. Ms. Lisa Morin is the budget director for Nexus Media, Inc. She would like to compare the daily travel expense for the sales staff and the audit staff. She collected the following sample information.

Audit (\$) 131 135 146 165 136 142

Sales (\$) 130 102 129 143 149 120 129

At the .10 significance level, can she conclude that the mean daily expenses are greater for the sales staff than the audit staff? What is the p-value?

Five-Step Procedure for Hypothesis Testing

1. Establish the hull hypothesis (H0) and the alternate hypothesis (H1).
2. Select the level of significance.
3. Select an appropriate test statistic.
4. Formulate a decision rule based on steps 1, 2, and 3 above.
5. Make a decision regarding the null hypothesis based on the sample information. Interpret the results of the test.
Here's a more direct answer for you to use a guide for your homework questions.
We certainly can not answer and perform all of the answers for you--yet, I will give answers to the 2 questions you have proposed here.
Hope this helps.

Question 12 - Indicates the Ho: Null hypothesized proportion as .52 or 52% are men drivers. Out of 300 random vehicles the ratio was actually observed as 300/170 or 57%.

This already gives an indication that the null hypothesis may be incorrect.
With an Alpha significance of .01 we would test this hypothesis. Using Statitical software or websites that will assist with obtaining the "p-value".

With this test performed it is found that the p-value is at .0415 which is greater than the alpha .01 level of significance.

Thus, we would reject the null hypothesis and replace it with the alternative, since with 95% confidence we are certain that the proportion of male drivers is greater that 52%.

Ho: p is equal to 52%
Ha: p is greater than 52%

Hypothesis test for proportion vs hypothesized value

Observed Hypothesized
0.57 0.52 p (as decimal)
171/300 156/300 p (as fraction)
171. 156. X
300 300 n

0.0288 std. error
1.73 z
.0415 p-value (one-tailed, upper)

Hope this helps. Tomy M. Hall, MS

ton_ty2275
Jun 28, 2007, 03:41 PM
I need help with the following 2 excersises. using the 5 steps of hypothesis testing and I need to show all calculations,

Use the five-step procedure for hypothesis testing in the following exercises

12. The National Safety Council reported that 52 per cent of American turnpike drivers are men. A sample of 300 cars traveling outbound on the New Jersey Turnpike yesterday revealed that 170 were driven by men. At the .01 significance level, can we conclude that a larger proportion of men were driving on the New Jersey Turnpike than the national statistics indicate?

17. Ms. Lisa Morin is the budget director for Nexus Media, Inc. She would like to compare the daily travel expense for the sales staff and the audit staff. She collected the following sample information.

Audit (\$) 131 135 146 165 136 142

Sales (\$) 130 102 129 143 149 120 129

At the .10 significance level, can she conclude that the mean daily expenses are greater for the sales staff than the audit staff? What is the p-value?

Five-Step Procedure for Hypothesis Testing

1. Establish the hull hypothesis (H0) and the alternate hypothesis (H1).
2. Select the level of significance.
3. Select an appropriate test statistic.
4. Formulate a decision rule based on steps 1, 2, and 3 above.
5. Make a decision regarding the null hypothesis based on the sample information. Interpret the results of the test.
Question 17 - You must perform calculations for the mean. The mean is the sum of the values divided by the number of values. Obtain the answers for the mean for both variables (Audit and Sales).

You could use descriptive statistical software or do this manually with the use of a calculator. In order to test the level of significance you would need to use software or a Stats website for assistance.

Performing the calculations:
Audit mean = 142.50 or 143 rounded
Sales mean = 128.86 or 129 rounded

Performing significance test for "p-value" yields: Using Mean vs. Hypothesized value
testing at Alpha .10

Audit p-value = .5000 which is greater than .10
Sales p-value = .5002 which is greater than .10

Thus, with this specific question--- at alpha .10 signficance we CAN NOT conclude that the Mean for the sales travel expenses is greater than the audit expenses.

Going further however, if the alpha level of significance were tested at .5 then we could conclude with 95% onfidence that the Audit sales were greater than that of Sales---since .5000 is equal to .5. Yet, the sales p-value of .5002 is greater than .5 thus we would chose Audit as the final answer at the .5 level of significance.

Descriptive statistics

Audit
count 6
mean 142.50
sample variance 149.90
sample standard deviation 12.24
minimum 131
maximum 165
range 34

Descriptive statistics

Sales
count 7
mean 128.86
sample variance 234.48
sample standard deviation 15.31
minimum 102
maximum 149
range 47

Hypothesis Test: Mean vs. Hypothesized Value

142.500 hypothesized value
142.500 mean Audit
12.243 std. dev.
4.998 std. error
6 n
5 df

0.00 t
.5000 p-value (one-tailed, upper)

Hypothesis Test: Mean vs. Hypothesized Value

128.860 hypothesized value
128.857 mean Sales
15.313 std. dev.
5.788 std. error
7 n
6 df

0.00 t
.5002 p-value (one-tailed, upper)