Joseph so
8 – 75.5%, about three fourths
10 – the standard deviation of the residual, or the average error between the horsepower
and predicted mpg had a standard deviation of 3.287
11 – y = 12.5 +.75x
b – y = 23.2 – 8x
c – y – 152, sy = 30
d – y – 25, r  .6
22
 a – I assume that the student is referring to the r^2, misinterpreting the meaning of
the r squared as a casual link between literacy and life expectancy. However as we know
r squared only represents the fraction of the data variation between the two variables.
B – slope of regression lines are the correlation coefficient multiplied by the standard
deviations of y or x. meaning that slop only shows the strength and association of the
regression line multiplied by the average distance the x and y points are from actual data.
Meaning that the slope can actually say that a 5% increase will actually raise life
expectancy by two years.
28 – A ride that is one foot higher will on average tend to be .242 seconds longer.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '08
 Ioudina
 Normal Distribution, Regression Analysis, Standard Deviation, regression line, high fuel efficiency

Click to edit the document details