Concept explainers
a.
Express the
Verify that
a.
Explanation of Solution
Calculation:
Consider,
Also, the sum of difference of each x value from mean is 0. That is,
When
When
Verification:
The expression given in 13.2 is given below:
Here,
Where,
The variance is calculated by using the formula
Thus,
Hence, the
b.
Use the fact that predicted value and residuals are independentof each other, the expression for
b.
Explanation of Solution
Calculation:
The expression for
The variance
Substituting the
Thus, the resultant equation is same as the Expression 13.2.
c.
Identify the changes in
c.
Explanation of Solution
From the expression,
It can be observed that as
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Chapter 13 Solutions
Probability and Stats. for Engineering.. (Looseleaf)
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