Question

Conduct a test of the null hypothesis that the mean height for all students in the...

Conduct a test of the null hypothesis that the mean height for all students in the Census at School database is equal to 155 cm vs the alternative that the mean Height is greater than 155 cm. Use a significance level of 0.05.

a. State the null and alternative hypotheses.

Ho: m = 155

Ha: m > 155

b. Provide the Statcrunch output table.

Hypothesis test results:

Variable

Sample Mean

Std. Err.

DF

T-Stat

P-value

Height

159.86

1.7311103

49

2.8074468

0.0036

c. Provide an explanation of the results (Is there statistically significant evidence for the alternative hypothesis?) You should reference your P-value in your explanation and explain how this led you to your conclusion.

2. Suppose you somehow find out that the actual mean height for the entire database population is 160 cm.

a. Looking back at your test from question 1, was the result of your test a correct decision, a Type I error, or a Type II error.

b. Explain (for example , did you reject a true null, fail to reject a false null, reject a false null, or fail to reject a true null).

3. Conduct a test of the null hypothesis that the proportion of all students in the Census at School database who take a car to school (column J) is equal to 50% vs. the alternative that the proportion is less than 50%. Use a significance level of 0.05.

Stat / proportion stats / 1 sample/with data . Column J is Travel_to_School and Success is ‘Car’.   Fill in the appropriate options for null proportion and direction of test.

a. State the null and alternative hypotheses.

Ho: p = 0.5

Ha: p < 0.5

b. Provide the Statcrunch output table.

a.     Hypothesis test results:

Variable

Count

Total

Sample Prop.

Std. Err.

Z-Stat

P-value

Travel_to_School

0

50

0

0.070710678

-7.0710678

<0.0001

c. Provide an explanation of the results (Is there statistically significant evidence for the alternative hypothesis?) You should reference your P-value in your explanation and explain how

4. Suppose you somehow find out that the actual proportion for the entire database population is 48 %.

a. Looking back at your test from question 1 3, was the result of your test a correct decision, a Type I error, or a Type II error.

b. Explain.

i need help with the questions in bold please and thank you

Homework Answers

Answer #1

1)

c)
since p value=0.0036 < α=0.05 , reject Ho
hence, there is enough evidence to conclude that true mean Height is greater than 155 cm at α=0.05

2)
a)
Type I error is rejecting null hypothesis when it is true , so it not type I error
Type II error is fail to reject false null hypothesis , so it is also not type II error

answer is correct Decision

b)
Decsion is
Reject a false Null

3)
p value is very small and less than α=0.05, so, reject Ho
there is enough evidence to conclude that true proportion is less than 50% at α=0.05


4)
a)
It is a coorect decision

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Then, answer the following five parts: Write down the null hypothesis. Write down the alternative hypothesis....
Then, answer the following five parts: Write down the null hypothesis. Write down the alternative hypothesis. Explain why you chose your hypotheses as such. Do a hypothesist test of your data at the α = 2% level of significance for the population proportion by carrying out the following five steps: View an example of how to use StatCrunch to compute the value Zα If it is a left-tailed test, what is the critical value, -z0.02? If it is a right-tailed...
does this data meet the assumptions for a two population proportion hypothesis using PHANTOMS Hypothesis test...
does this data meet the assumptions for a two population proportion hypothesis using PHANTOMS Hypothesis test results: Difference Count1 Total1 Count2 Total2 Sample Diff. Std. Err. Z-Stat P-value p1 - p2 9 31 8 30 0.023655914 0.1148271 0.20601333 0.8368
Questions D-F d) You conduct a hypothesis test for the population proportion. After you calculate the...
Questions D-F d) You conduct a hypothesis test for the population proportion. After you calculate the z test statistic, you find that your p-value = 0.059. Using alpha (α) = 0.05 level of significance, what is your decision regarding the null hypothesis? Choose from the following. - Reject the null hypothesis and reject the alternative hypothesis - Accept the null hypothesis - Do not reject the null hypothesis - Reject the null hypothesis and accept the alternative hypothesis e) You...
When we conduct a hypothesis test, there are two ways to make a mistake. The null...
When we conduct a hypothesis test, there are two ways to make a mistake. The null hypothesis might be correct, and we end up rejecting it. This is called a Type I error. On the other hand, the null hypothesis might be false, and we fail to reject it. This is called a Type II error. Either type of error can be costly, though not necessarily equally costly. In the following two scenarios, think about what is the alternative hypothesis?...
Test the null hypothesis H0:p=0.5against the alternative hypothesis HA:p<0.5, when 89 individuals in a random sample...
Test the null hypothesis H0:p=0.5against the alternative hypothesis HA:p<0.5, when 89 individuals in a random sample of 218 have a characteristic of interest. Proportions are very sensitive to round-off error. Please ensure that you attempt to round p^as little as possible. a) Calculate the value of the z test statistic, for testing the null hypothesis that the population proportion is 0.5. Round your response to at least 3 decimal places. b) The p-value falls within which one of the following...
Test the null hypothesis H0:p=0.5against the alternative hypothesis HA:p<0.5, when 92 individuals in a random sample...
Test the null hypothesis H0:p=0.5against the alternative hypothesis HA:p<0.5, when 92 individuals in a random sample of 219 have a characteristic of interest. Proportions are very sensitive to round-off error. Please ensure that you attempt to round p^as little as possible. a) Calculate the value of the z test statistic, for testing the null hypothesis that the population proportion is 0.5. Round your response to at least 3 decimal places. b) The p-value falls within which one of the following...
1). Conduct the appropriate hypothesis test with the following information, and provide your p-value as your...
1). Conduct the appropriate hypothesis test with the following information, and provide your p-value as your final answer.  The null hypothesis states that H0:= 250 versus the alternative Ha: > 250. The sample of size 26 resulted in a mean of 255.0 and a standard deviation of 8.79. Find the p-value in this example. 2). Conduct the appropriate hypothesis test with the following information, and provide your p-value as your final answer.  The null hypothesis states that H0: = 0.75 versus the...
The null hypothesis states there will be no difference in scores on the ADS between those...
The null hypothesis states there will be no difference in scores on the ADS between those who receive the standard treatment program and those who receive the standard treatment program plus Mindfulness Therapy. The output from the analysis is below. The results are t(19) = 1.554, p = .137. Paired Sample Statistics Mean N Std Deviation Std. Error Mean Pair 1 Standard Std. Mindfulness 12.8000 10.9500 20 20 3.81962 4.28553 .85409 .95827 Paired Samples Correlations N Correlations Sig Pair 1...
The null hypothesis is the prediction that there are no differences between the mean of the...
The null hypothesis is the prediction that there are no differences between the mean of the population and the mean of your sample. Question 1 options: True False Save Question 2 (1 point) The hypothesis that your sample mean is significantly different from the population mean is called the Alternative hypothesis or _________________. Question 2 options: a) Null hypothesis b) Research Hypothesis c) One-Tailed Test d) Two-Tailed test Save Question 3 (1 point) If you are running a test to...
The primary purpose of hypothesis testing is to attempt to reject the null hypothesis not to...
The primary purpose of hypothesis testing is to attempt to reject the null hypothesis not to accept the alternative hypothesis. True False In hypothesis testing, a Type 1 error is failing to reject the null hypothesis when it is true. failing to reject the null hypothesis when it is false. rejecting the null hypothesis when it is true. rejecting the null hypothesis when it is false. In general, the power of a statistical test is the probability that a test...