Question

In: Statistics and Probability

If, ?2 = 64, and ? = 20, we can say with 95% confidence that the...

If, ?2 = 64, and ? = 20, we can say with 95% confidence that the standard deviation is between 37.02 and
136.52.

a. True
b. False
c. Uncertain
Explain:-

Expert Solution

Solution:

It is

False

Explanation:

Solution :

Given that,

c = 95% = 0.95

s² = 64

s = 8

n = 20

d.f. = n - 1 = 20 - 1 = 19

= 1 - 0.95= 0.05

/ 2 = 0.025

1 - ( / 2) = 0.975

Now , using chi square table ,

_/2,df = _0.025,19 = 32.852

_1-_/2,df = _0.975,19 = 8.907

The 95% confidence interval for is,

8 [( 20- 1 ) / 32.852] < < 8 [( 20 - 1 ) / 8.907]

6.08 < < 11.68

So ,

False

orchestra answered 1 year ago

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