Regression Prob & Stats

Estimate the correlation coefficient for this scatterplot.

• A) r = 1.2

• B) r = 0.89

• C)r = 0

• D) r = -0.89

What type of correlation exists between the outside temperature and the amount of layers you wear.

• A) Positive correlation

• B) Negative correlation

• D) No correlation

What is the best definition of the least squares regression line?

• The line that minimizes the squares of the horizontal distances between the data points and the line.
• The line that minimizes the squares of the vertical distances between the data points and the line.
• The line that minimizes the vertical distances between the data points and the line.
• The line that passes through the most number of data points.

True or False: The residual value can be calculated by subtracting: "predicted y - actual y"

• True

• False

If Joe worked 30 hours, how much is he expected to earn?

• $600
• $200
• $1000
• $800

The correlation coefficient r is a value between

• 0 and 1
• 0 and 100
• -1 and 1
• -2 and 2

Determine the least squares regression line.

• y = -0.517x + 9.143
• y = -0.514x + 9.314
• y = -0.56x + 9.54
• y = -0.534 + 9.59

Is r = -0.87 strong, moderate, or weak?

• strong

• moderate

• weak

The equation of the best-fit line is
y(hat) = 1.3 + 0.73x.  What is the residual for the point (4, 7)?

• 2.78
• 3.00
• 4.00
• 4.22

What type of correlation best describes the scatterplot shown.

• positive, weak

• positive, strong

• negative, weak

• no correlation