# Math 45 - hw 2 - a graph. 5. Now look at the residuals as...

This preview shows pages 1–2. Sign up to view the full content.

Math 45X 7:30-8:30 July 4, 2011 The following table give the life expectancy at birth of females born in the United States in various years from 1970 to 2005. Year of Birth Life Expectancy (Years) Residuals 1970 74.7 75.514 -0.814 1975 76.6 76.255 5 0.3445 1980 77.4 76.997 0.403 1985 78.2 77.738 5 0.4615 1990 78.8 78.48 0.32 1995 78.9 79.221 5 -0.3215 2000 79.5 79.963 -0.463 2005 80.8 80.704 5 0.0955 1. Find an equation for the least squares line for these data, using year of birth as the independent variable. 2. Use the regression equation to guess a value of the life expectancy of females born in 1990. 3. Compare answer with the actual life expectancy for females born in 1990, which was 48.3 years. Are you surprised? There was a 16.833-year difference, which was very surprising. 4. Find the life expectancy predicted by the regression equation for each year in the table, and subtract it from the value in the second column. This gives a table of residuals. Plot the residuals as points on

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.

Unformatted text preview: a graph. 5. Now look at the residuals as fresh data set and see if you can sketch the graph of a smooth function that fits the residuals well. How easy do you think it will be to predict the life expectancy at birth of females born in 2015? It will indeed be very easy, because all we have to do is to substitute the value of x=115 to the regression equation, which will give us 82.1875 years of life expectancy. (murag sa residuals ni nga question) 6. What will happen if you try linear regression on the residuals? Why does this result make sense? 7. Since most of the females born in 1995 are still alive, how did the Public Health Service come up with a life expectancy of 78.9 years for these women? Graph to Number 4 & 5...
View Full Document

## This note was uploaded on 12/16/2011 for the course ACCOUNTANC 506 taught by Professor Mr.reyes during the Spring '11 term at University of the Philippines Diliman.

### Page1 / 2

Math 45 - hw 2 - a graph. 5. Now look at the residuals as...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online