Exam 9: Introduction to Estimation

The lower limit of the 90% confidence interval for the population proportion p , given that n = 400 and = 0.10, is 0.0247.

Under what condition(s)does the test statistic for p have an approximate normal distribution?

Define unbiasedness.

Physicians A random sample of 200 physicians shows that there are 36 of them who make at least $400,000 a year. {Physicians Narrative} Compute the p -value and explain how to use it to test the hypotheses.

In testing a hypothesis about a population proportion p , the z test statistic measures how close the computed sample proportion has come to the hypothesized population parameter.

Define relative efficiency.

The bound on the error of estimation is the ____________________ amount of sampling error that we are willing to tolerate.

The confidence interval estimate of the population mean is constructed around the sample mean.

The test statistic for p is approximately normal when np and n (1 - p )are both ____________________.

The sample proportion is a consistent estimator of the population proportion p because it is unbiased and the variance of is p (1 - p )\ n , which grows smaller as n grows larger.

Is the sample mean a consistent estimator of the population mean? Explain

After calculating the sample size needed to estimate a population proportion to within 0.04, your statistics professor told you the maximum allowable error must be reduced to just .01. If the original calculation led to a sample size of 800, the sample size will now have to be:

____________________ estimators reflect the effects of larger sample sizes, but ____________________ estimators do not.

It is intuitively reasonable to expect that a larger sample will produce more ____________________ results.

The sampling error for a confidence interval is also defined as the ____________________ of ____________________.

If the population standard deviation is guesstimated, and it turned out to be smaller than you assumed, then the sample size you calculated is ____________________ than it needs to be.

The sample variance is a point estimate of the population variance.

When a population is small, it is necessary to include the ____________________ factor in our hypothesis tests and confidence interval estimators for p .

The sample ____________________ is an unbiased estimator for the population mean.

Draw sampling distributions of a consistent estimator for m where one sample mean is larger than the other.