Question 2 of 7

The table below gives the age and bone density for five randomly selected women. Using this data, consider the equation of the regression line, [tex]\hat{y}=b_0+b_1 x[/tex], for predicting a woman's bone density based on her age. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. In practice, it would not be appropriate to use the regression line to make a prediction if the correlation coefficient is not statistically significant.

[tex]\[
\begin{tabular}{|c|c|c|c|c|c|}
\hline
Age & 34 & 45 & 48 & 60 & 65 \\
\hline
Bone Density & 357 & 341 & 331 & 329 & 325 \\
\hline
\end{tabular}
\][/tex]

Step 6 of 6: Find the value of the coefficient of determination. Round your answer to three decimal places.



Answer :

To determine the coefficient of determination, we first carry out a linear regression analysis on the given data sets for age and bone density. Here is the step-by-step process:

1. Given Data:
- Age: [tex]\( [34, 45, 48, 60, 65] \)[/tex]
- Bone Density: [tex]\( [357, 341, 331, 329, 325] \)[/tex]

2. Perform Linear Regression:
- To fit a linear regression model, we find the best-fitting line of the form [tex]\(\hat{y} = b_0 + b_1 x\)[/tex].

3. Calculate Regression Parameters:
- Slope ([tex]\(b_1\)[/tex]): -0.9638870650032828
- Intercept ([tex]\(b_0\)[/tex]): 385.1799080761655

4. Correlation Coefficient ([tex]\(r\)[/tex]): -0.9266111039699972

5. P-value: 0.023601515119593738 (which is used to determine the statistical significance of the correlation coefficient, though not directly required for finding [tex]\(R^2\)[/tex]).

6. Calculate Coefficient of Determination ([tex]\(R^2\)[/tex]):
- The coefficient of determination is the square of the correlation coefficient. [tex]\( R^2 = r^2 \)[/tex].

[tex]\[ R^2 = (-0.9266111039699972)^2 \][/tex]

[tex]\[ R^2 = 0.8586081380004971 \][/tex]

7. Round to Three Decimal Places:
- The rounded value of [tex]\( R^2 \)[/tex] to three decimal places is [tex]\( 0.859 \)[/tex].

Thus, the value of the coefficient of determination, rounded to three decimal places, is [tex]\( \boxed{0.859} \)[/tex].