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Chapter 8: Q8 (page 408)

Chi-Square Test In a test of the claim that σ = 15 for the population of IQ scores of professional athletes, we find that the rightmost critical value is χR2 = 40.646. Is the leftmost critical role="math" localid="1649228478554" χL2 value equal to -40.646?

Short Answer

Expert verified

No, the left most critical value χL2 is not equal to -40.646.

Step by step solution

01

Given information

It is claimed that the population standard deviation of IQ scores is equal to 15.

The right most critical value χR2 is equal to 40.646.

02

Critical Value of   χ2

It is known that the chi-square distribution can assume values that are positive as chi-square is the sum of the square of the normal distribution.

A squared value can never be negative.

Thus, the critical value of the chi-square distribution can never be negative.

Therefore, the value of χL2 cannot be equal to -40.646.

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