8.5 Practice Due Fri. 5/10

Last updated almost 2 years ago

10 questions

Required

3

Required

5

Required

5

Required

4

Required

3

Required

3

Required

5

Required

5

Required

4

Required

3

Library

8.5 Practice Due Fri. 5/10

Last updated almost 2 years ago

10 questions

Required

3

Required

5

Required

5

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48   49   45   51   49   53   48   44   47   50   46   48

You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Use statsmedic.com/applets, 1 quantitative variable single group, to find the mean and standard deviation.
What is the sample mean? _______ round to 3 places past the decimal
What is the mean from the null hypothesis? _______ 
What is the standard error for the sampling distribution of the mean? _______ Round to 3 places past the decimal. See 8.5 for the formula if needed.
Calculate the standardized test statistic (the t statistic) _______ round to 3 places
 .   

Required

4

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48   49   45   51   49   53   48   44   47   50   46   48
You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Degrees of freedom = _______ 
Is this a one tailed or a two tailed test? Enter 1 or 2 _______ 
Use the absolute value of the t statistic.
What are the two percentages that correspond to these values? Enter in the same order, keep in decimal form.
 _______  to  _______

Required

3

Required

3

Required

5

Required

5

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?”
Here are the data (in hours):
9  6  8  6  8  8  6  6.5  6  7  9  8  7  7
4  3  4  5  6  11  6  3  6  6  10  7  4.5  9

The professor wants to perform a test at the α = 0.05 significance level.
Use statsmedic.com/applets, 1 quantitative variable single group, to find the mean and standard deviation.
What is the sample mean? _______ keep all decimal places
What is the mean from the null hypothesis? _______ 
What is the standard error for the sampling distribution of the mean? _______ Round to 3 places past the decimal. See 8.5 for the formula if needed.
Calculate the standardized test statistic (the t statistic) _______ round to 3 places
 .   

Required

4

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?”
Here are the data (in hours):
9  6  8  6  8  8  6  6.5  6  7  9  8  7  7
4  3  4  5  6  11  6  3  6  6  10  7 4.5  9

The professor wants to perform a test at the α = 0.05 significance level. Continue with the significance test from above.
Degrees of freedom = _______ 
Is this a one tailed or a two tailed test? Enter 1 or 2 _______ 
Use the absolute value of the test statistic.
What are the two percentages that correspond to these values? Enter in the same order
 _______   to  _______

Required

3

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48 49 45 51 49 53 48 44 47 50 46 48

You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Identify the null and alternative hyothesis.
Define the parameter of interest.

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48 49 45 51 49 53 48 44 47 50 46 48

You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Confirm that the conditions for conducting a significance test for a mean have been met:

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48   49   45   51   49   53   48   44   47   50   46   48

You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Use statsmedic.com/applets, 1 quantitative variable single group, to find the mean and standard deviation.
What is the sample mean? _______ round to 3 places past the decimal
What is the mean from the null hypothesis? _______ 
What is the standard error for the sampling distribution of the mean? _______ Round to 3 places past the decimal. See 8.5 for the formula if needed.
Calculate the standardized test statistic (the t statistic) _______ round to 3 places
 .   

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48   49   45   51   49   53   48   44   47   50   46   48
You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Degrees of freedom = _______ 
Is this a one tailed or a two tailed test? Enter 1 or 2 _______ 
Use the absolute value of the t statistic.
What are the two percentages that correspond to these values? Enter in the same order, keep in decimal form.
 _______  to  _______

Based on the results in the previous question, using an alpha level of 5%, do you have convincing evidence that the radio station is exaggerating about the number of minutes of music they play each hour?

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?”
Here are the data (in hours):
9 6 8 6 8 8 6 6.5 6 7 9 8 7 7
4 3 4 5 6 11 6 3 6 6 10 7 4.5 9

The professor wants to perform a test at the α = 0.05 significance level.

Identify the null and alternative hypotheses.
Define the parameter of interest.

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?”
Here are the data (in hours):
9 6 8 6 8 8 6 6.5 6 7 9 8 7 7
4 3 4 5 6 11 6 3 6 6 10 7 4.5 9

The professor wants to perform a test at the α = 0.05 significance level.

Check that the conditions for performing the test are met.
Five answers please.

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?”
Here are the data (in hours):
9  6  8  6  8  8  6  6.5  6  7  9  8  7  7
4  3  4  5  6  11  6  3  6  6  10  7  4.5  9

The professor wants to perform a test at the α = 0.05 significance level.
Use statsmedic.com/applets, 1 quantitative variable single group, to find the mean and standard deviation.
What is the sample mean? _______ keep all decimal places
What is the mean from the null hypothesis? _______ 
What is the standard error for the sampling distribution of the mean? _______ Round to 3 places past the decimal. See 8.5 for the formula if needed.
Calculate the standardized test statistic (the t statistic) _______ round to 3 places
 .   

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?”
Here are the data (in hours):
9  6  8  6  8  8  6  6.5  6  7  9  8  7  7
4  3  4  5  6  11  6  3  6  6  10  7 4.5  9

The professor wants to perform a test at the α = 0.05 significance level. Continue with the significance test from above.
Degrees of freedom = _______ 
Is this a one tailed or a two tailed test? Enter 1 or 2 _______ 
Use the absolute value of the test statistic.
What are the two percentages that correspond to these values? Enter in the same order
 _______   to  _______

Based on the results in the previous question, using an alpha level of 5%, do you have convincing evidence that the professor's students don't get the required 8 hours of sleep?

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48   49   45   51   49   53   48   44   47   50   46   48

You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Identify the null and alternative hyothesis.
Define the parameter of interest.

P = true proportion of music played (in minutes) during each hour by this station

μ = true proportion of music played (in minutes) during each hour by this station

μ = true mean amount of music played (in minutes) during each hour by this station

P = true mean amount of music played (in minutes) during each hour by this station

A “classic rock” radio station claims to play an average of 50 minutes of music every hour. However, it seems that every time you tune into this station, a commercial is playing. To investigate the station’s claim, you randomly select 12 different hours during the next week and record how many minutes of music the station plays in each of those hours. Here are the data:
48   49   45   51   49   53   48   44   47   50   46   48

You would like to perform a test to see if the average of 50 minutes of music every hour is actually an exaggeration.
Confirm that the conditions for conducting a significance test for a mean have been met:

Normal/Large Counts condition is met

Per the Central Limit Theorem the shape follows a normal distribution, n >30

The sample size is too small (12 < 30) and

Random Sample condition is met

Random Sample condition is not met

Statsmedic.com/applets does not show that the distribution is roughly normal.

Large Counts condition is met

"you randomly select 12 different hours during the next week"

Normal/Large Counts condition is not met, but we will proceed with caution

Statsmedic.com/applets shows that the distribution is roughly normal.

Based on the results in the previous question, using an alpha level of 5%, do you have convincing evidence that the radio station is exaggerating about the number of minutes of music they play each hour?

P-value > alpha level

P-value < alpha level

we do not have convincing evidence that the radio station plays less than 50 minutes of music per hour

we have convincing evidence that the radio station plays less than 50 minutes of music per hour

the radio station is exaggerating

the radio station is not exaggerating

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?” 
Here are the data (in hours):
9  6  8  6  8  8  6  6.5  6  7  9  8  7  7
4  3  4  5  6  11  6  3  6  6  10  7 4.5  9

The professor wants to perform a test at the α = 0.05 significance level.

Identify the null and alternative hypotheses.
Define the parameter of interest.

μ is the true proportion of amount of sleep last night in the population of students at his college

P is the true proportion of amount of sleep last night in the population of students at his college

μ is the true mean amount of sleep last night in the population of students at his college

P is the true mean amount of sleep last night in the population of students at his college

A professor suspects that students at his school are getting fewer than 8 hours of sleep a night, on average. To test his belief, the professor asks a random sample of 28 students, “How much sleep did you get last night?” 
Here are the data (in hours):
9  6  8  6  8  8  6  6.5  6  7  9  8  7  7
4  3  4  5  6  11  6  3  6  6  10  7 4.5  9

The professor wants to perform a test at the α = 0.05 significance level.

Check that the conditions for performing the test are met.
Five answers please.

Normal/Large Sample condition has not been met, proceed with caution

Random Sample condition has not been net

Sample distribution is roughly normal

'SRS of 28 students'

N=30, 30 < 30

'Random sample of 28 students'

Sample distribution is strongly skewed

Normal/Large Sample condition has been met

 Random Sample condition is met

n=28, 28<30

Based on the results in the previous question, using an alpha level of 5%, do you have convincing evidence that the professor's students don't get the required 8 hours of sleep?

P-value < alpha level

we do not have convincing evidence that the students get less than 8 hours of sleep per night

P-value > alpha level

the does not need to be concerned

the professor is correct to be concerned

we have convincing evidence that the students get less than 8 hours of sleep per night