Question 1

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below:  {Longevity and Salary Narrative} Determine the least squares line, and use it to estimate the value of y for x = 6.

Accepted Answer

The answer of Longevity and Salary A sample of eight...

Question 2

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below:  {Longevity and Salary Narrative} Draw the scatter diagram and plot the least squares line.

Accepted Answer

The answer of Longevity and Salary A sample of eight...

Question 3

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below:  {Longevity and Salary Narrative} 
 a. Calculate the coefficient of correlation, and comment on the relationship between x and y . 
 b. Give a possible reason that the correlation is negative.

Accepted Answer

The answer of Longevity and Salary A sample of eight...

Question 4

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below:  {Longevity and Salary Narrative} 
 a. Calculate and interpret the covariance between x and y . 
 b. Give a possible reason that the covariance is negative.

Accepted Answer

The answer of Longevity and Salary A sample of eight...

Question 5

Consider the following data:  
 a. Calculate the covariance and the coefficient of correlation for the sample. 
 b. What do these statistics tell you about the relationship between x and y ?

Accepted Answer

The answer of Consider the following data:  
 a....

Question 6

How is the value of the correlation coefficient r affected in each of the following cases? 
 a. Each x value and y is multiplied by 4. 
 b. Each x value is switched with the corresponding y value. 
 c. Each x value is increased by 2.

Accepted Answer

The answer of How is the value of the correlation...

Quiz 3: Numerical Descriptive Techniques

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below: {Longevity and Salary Narrative} Determine the least squares line, and use it to estimate the value of y for x = 6.

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below: {Longevity and Salary Narrative} Draw the scatter diagram and plot the least squares line.

Longevity and Salary A sample of eight observations of variables x (years of experience)and y (salary in $1,000s)is shown below: {Longevity and Salary Narrative} a. Calculate and interpret the covariance between x and y . b. Give a possible reason that the covariance is negative.

Consider the following data: a. Calculate the covariance and the coefficient of correlation for the sample. b. What do these statistics tell you about the relationship between x and y ?

How is the value of the correlation coefficient r affected in each of the following cases? a. Each x value and y is multiplied by 4. b. Each x value is switched with the corresponding y value. c. Each x value is increased by 2.