Question

A least squares regression line was calculated to relate the length​ (cm) of newborn boys to their weight in kg. The line is weight equals negative 5.31 plus 0.1694 length. A newborn was 48 cm long and weighed 3 kg. According to the regression​ model, what was his​ residual?

Answer 1

0.1788

Explanation:

The regression equation relates the length of newborn to their weight, in kg.

The equation is

`w=-5.31+0.1694l`

Where

w is weight in kg

l is length in cm

The residual is the difference in observed value and predicted value

The observed value is 3kg . Now let's find the predicted value by plugging in 48 into the equation (in l):

`w=-5.31+0.1694l\\w=-5.31+0.1694(48)\\w=2.8212`

Residual = 3 - 2.8212 = 0.1788