7.3: A newborn was 48 cm long and weighed 3 kg. According to the regression​ model, what was his​ residual? What does that say about​ him?

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=−6.07+0.1693 length. A newborn was 48 cm long and weighed 3 kg. According to the regression​ model, what was his​ residual? What does that say about​ him?

What was his​ residual?

___________ kg ​(Round to three decimal places as​ needed.)

Answer 1

Residual is typically defined as actuals minus predicted.

The prediction is calculated from W = −6.07 + 0.1693L so W = −6.07 + 0.1693(48) = 2.0564 kg

The actual was 3 kg

So the residual is 3 - 2.0564 = 0.9436 or (rounded to 3 decimal places) 0.944 kg

So we can say his weight is 0.944 kg above average for his length