Question

Find the regression​ equation, letting overhead width be the predictor​ (x) variable. Find the best predicted weight of a seal if the overhead width measured from a photograph is 1.7 cm. Can the prediction be​ correct? What is wrong with predicting the weight in this​ case? Use a significance level of 0.05.

Overhead Width​ (cm)	8.2	7.3	9.4	7.5	7.4	8.7
Weight​ (kg)	165	158	240	134	152	213

The regression equation is

ModifyingAbove y with caretyequals=_____+______x.

​(Round to one decimal place as​ needed.)

The best predicted weight for an overhead width of 1.7 cm is

_____ kg.

​(Round to one decimal place as​ needed.)

Can the prediction be​ correct? What is wrong with predicting the weight in this​ case?

A.

The prediction cannot be correct because there is not sufficient evidence of a linear correlation. The width in this case is beyond the scope of the available sample data.

B.

The prediction cannot be correct because a negative weight does not make sense. The width in this case is beyond the scope of the available sample data.

C.

The prediction cannot be correct because a negative weight does not make sense. The regression does not appear to be useful for making predictions.

D.

The prediction can be correct. There is nothing wrong with predicting the weight in this case.

Answer 1

The statistical software output for this problem is:

Hence,

Regression equation:

y = -189.3 + 45.3 x

Best predicted weight = -112.3

The prediction cannot be correct because a negative weight does not make sense. The width in this case is beyond the scope of the available sample data. Option B is correct.