Question

The eggs of a species of bird have an average diameter of 23 mm and an SD of 0.45 mm. The weights of the chicks that hatch from these eggs have an average of 6 grams and an SD of 0.5 grams. The correlation between the two variables is 0.75 and the scatter diagram is roughly football shaped. Find the regression estimate of the weight of a chick that hatches from an egg 24 mm in diameter.

Answer 1

\[\rho=\frac{Covariance(X,Y)}{\sigma _{x} \sigma _{y}}\]
\[0.75=\frac{Cov(X,Y)}{0.45\times 0.5}\]
\[Cov(X,Y)=0.16875=E[(X-E(X))(Y-E(Y))]=E[(24-23)(X-6)]\]
\[0.16875=E[X-6]\]
E(X) = 6.169 grams

Answer 2

@sinetifik Do you understand?

Answer 3

confused