It may seem odd, but one of the ways biologists can tell how old a lobster is involves measuring the concentration of a pigment called neurolipofuscin in the eyestalk of a lobster. (We are not making...

It may seem odd, but one of the ways biologists can tell how old a lobster is involves measuring the concentration of a pigment called neurolipofuscin in the eyestalk of a lobster. (We are not making this up!) Biologists wondered if it was sufficient to measure the pigment in just one eye stalk, which would be the case if there is a strong relationship between the concentration in the right and left eyestalks.

Suppose pigment concentration (as a percentage of tissue sample) was measured in both eyestalks for 39 lobsters, resulting in the following summary quantities.

n
=

39
Σx
=

86.8
Σy
=

84.1

Σxy
=

281.1
Σx2
=

286.0
Σy2
=

284.8
An alternative formula for computing the correlation coefficient that is based on raw data and is algebraically equivalent to the one given in the text is

r =

Σxy −

(Σx)(Σy)
n

Σx2 −

(Σx)2
n

Σy2 −

(Σy)2
n
.
Use this formula to calculate the value of the correlation coefficient. (Round your answer to three decimal places.)

r =

Interpret this value.

There is no linear relationship between the concentrations of neurolipofuscin in the right and left eyestalks.

There is a strong negative linear relationship between the concentrations of neurolipofuscin in the right and left eyestalks.

There is a weak negative linear relationship between the concentrations of neurolipofuscin in the right and left eyestalks.

There is a weak positive linear relationship between the concentrations of neurolipofuscin in the right and left eyestalks.

There is a strong positive linear relationship between the concentrations of neurolipofuscin in the right and left eyestal