# Linear Regression Lines

Answer each question in order. Write the number of the question and answer all parts thoroughly. Use complete sentences and show all required work.

Project for Unit 1

Infant Mortality Data - Linear Regression Lines

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The following table shows the mortality rates (in deaths per 1000 live births) for male and female infants, of all races, in the United States, from 1980 to 1997.

Year Male Female

1980 13.9 11.2

1981 13.1 10.7

1982 12.8 10.2

1983 12.3 10.0

1984 11.9 9.6

1985 11.9 9.3

1986 11.5 9.1

1987 11.2 8.9

1988 11.0 8.9

1989 10.8 8.8

1990 10.3 8.1

1991 10.0 7.8

1992 9.4 7.6

1993 9.3 7.4

1994 8.8 7.2

1995 8.3 6.8

1996 8.0 6.6

1997 8.0 6.5

1. Write at least two important conclusions from observing the data in the table.

2. Make a neat and careful graph entitled Infant Mortality Rates by putting Year on the horizontal axis and Number of Infant deaths (per thousand) on the vertical axis. Use the year 1980 as t = 0, and plot both sets of data on the same axis. The resulting graphs should be a series of dots (that is, a scatter plot); use two different styles of dots, for instance, squares and pulses. Do not connect the dots with a line. Label which graph is for males and which is for females.

3. Use your calculator to find the linear regression lines for both the male and femal data sets. Write the equations of the linear regression lines that the calculator gives you, using 4 decimal places for a and b in y = ax + b (x is really the variable t). label which equation represents male infant deaths and which is female infant deaths.

Please see attached.

#### Solution Summary

Linear regression lines are examined for infant mortality data. The required work is given.