Quiz 2.3-2.4 Review

What is an outlier?

• A value that is much less or much greater than the other values in a data set.
• The difference between the upper and lower quartiles of a data set.
• The mean of the distances from each data value in a set to the mean of a set.
• The difference between the greatest and least numbers in a data set.

If r = -1, then this implies that there is a negative correlation between at least two variables.

• True
• False

The coefficient of determination is _______.

• r²
• r
• y hat
• x

All of these mean the same thing except:

• LSRL
• line of best fit
• regression line
• line of demarcation

The table shown is comparing a person's foot length to their height in cm. What might the height of a person be with a foot length of 30 cm?

• 185 cm
• 180 cm
• 190 cm
• 192 cm

The table shown is comparing a person's foot length to their height in cm. What is the relationship between foot length and height?

• r² = .98
• r² = .94
• r² = .14
• r² = .34

What is the line of best fit?

• f(x)= 5x+1.82
• cannot be determined
• f(x)= 1.82x + 5.02
• f(x)= 1.1x + 4.2

What is the difference between correlation and regression?

• correlation is about ratio data and regression is about trinomial data
• correlation is about describing and regression is about predicting
• regression is about describing and correlation is about predicting
• they are exactly the same

If I tell you that the correlation between two variables is .50, what is the variance accounted for (i.e. what % of the change in y is explained by the change in x)?

• .50
• .25
• .75
• .10

If our regression equation is ŷ = 2.5x + 10, what is our predicted value of y if x =50.

• 135

• 120

• 55

• 50