1. Suppose it is known that the IQ scores of a certain population of adults are...

1. Suppose it is known that the IQ scores of a certain population of adults are approxi- mately normally distributed with a standard deviation of 15. A simple random sample of 25 adults drawn from this population had a mean IQ score of 105.

a) Would we be able to reject Ho if we were to test it at 1% significance level? Explain.

b)Construct and interpret the 95% confidence interval for population average IQ from these data.

c)Based on the 95% CI, is there evidence at 5% significance level that the average IQ in this population is not equal to 100? Explain.

Solutions

Expert Solution

Interpretation: We are 95% confident that the population mean will fall in above interval.

c) population mean = 100 falls in above 95% confidence interval hence we fail to reject H0.

Hence there is evidence at 5% significance level that the average IQ in this population is not equal to 100

Hope this will help you. Thank you :)

milcah answered 8 months ago

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