3.11 Quiz 12: linear regression and correlation

If there is a linear relationship between the quantity of food a person consumes per day and the person’s weight, the quantity of food a person consumes per day is the ______________.

• A

  independent variable

• B

  Unable to determine

• C

  dependent variable

A correlation coefficient for 9 pairs of data is calculated to be -0.213. Is the relationship between the variables statistically significant?

• A

  Unable to determine

• B

  No

• C

  Yes

Consider the following pairs of data (independent variable given first):

• (17, 56)
• (13, 48)
• (35, 65)
• (89, 146)
• (55, 121)
• (86, 130)

Calculate the Least Squares Line.

• A

  y-hat = -20.93 + 0.73x

• B

  y-hat = 33.33 + 1.24x

• C

  y-hat = 1.24 + 33.3x

• D

  y-hat = 0.73 - 20.93x

A correlation coefficient for 6 pairs of data is calculated to be 0. Then,

• A

  there is positive correlation between the variables.

• B

  the Line of Best Fit has a negative slope.

• C

  there is negative correlation between the variables.

• D

  the Line of Best Fit has a slope of zero.

A study is done to see if there is a linear relationship between the life expectancy of an individual and the year of birth. The year of birth is the ______________.

• A

  Unable to determine

• B

  dependent variable

• C

  independent variable

If you determine a point is an outlier, you would

• A

  ignore it.

• B

  always delete it and then recalculate the line of best fit.

• C

  examine it carefully and try to determine what is causing it to be an outlier.

• D

  use it in the calculation of the Sum of Squared Errors.

Consider the following pairs of data (independent variable given first):

• (17, 56)
• (13, 48)
• (35, 65)
• (89, 146)
• (55, 121)
• (86, 130)

Find the estimated y for an x-value of 40.

• A

  -836

• B

  1334

• C

  83

• D

  8.3

A study is done to see if there is a linear relationship between the calendar year and the population of a particular country. The calendar year is the ______________.

• A

  dependent variable

• B

  Unable to determine

• C

  independent variable

Consider the following pairs of data (independent variable given first):

• (16, 56)
• (10, 98)
• (35, 105)
• (4, 70)
• (12, 121)

The relationship between the two variables is ______________.

• A

  linear

• B

  not significant

• C

  parabolic

• D

  exponential

Consider the following pairs of data (independent variable given first):

• (16, 56)
• (10, 98)
• (35, 105)
• (4, 70)
• (12, 121)

The regression line is ______________.

• A

  steeply sloped downward

• B

  almost horizontal

• C

  steeply sloped upward