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We deal with a very different statistic called chi-squared
Mathematicians and statisticians figured out that the standard deviation could
be tested with the following formulas:
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Ages of Canadians
We stated
before that the mean age of Canadians is about 38 years with a standard deviation
close to 26.1 years.Brigita has a sample of 81 Canadian ages and she believes it to be representative of all Canadians.
She claims her standard deviation is equal to 26.1 years (or close to this value.)
Test her claim at the 90% level if she comes up with s=18.3 years in her sample.
(We're testing that
=
26.1) |
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).
The null hypotheses in this section will feature statements such as:
P= 0.45 , p 
0.056
, p 
0.771
, = 22.1 ,0.003
, 5.098
(Proportions are always between 0.000 and 1.000; standard deviations are positive.)
Testing a claim about a proportion
For this hypothesis testing, the standard normal tables are again being used.
Formulas we need: 
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Solution:
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Example Question:
The Prime
Minister claims he has the support of more than 50% of Canadians on security
issues.
(Claim is p > 0.5000 )
The final tally was that 683 people did support the PM on security issues.
Test the PM's claim at the 95% confidence level.
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Elizabeth's
survey of male heights (in inches) included the following:
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Test
Elizabeth's claim at the 99% level that standard deviation is greater than 2.9
inches.
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Response rate for a survey
A response
rate of 75% for a survey is considered quite good.
Harold claims he got a 75% response rate last time.
His survey polled 600 members and 432 members responded.
Test
Harold's claim at the 95% confidence level.
(Claim is p = 0.75)