Question

In: Statistics and Probability

A survey of 25 randomly selected psychiatrists found an average hourly wage (including benefits) of $65.00... A survey of 25 randomly selected psychiatrists found an average hourly wage (including benefits) of$65.00 per hour. The sample standard deviation was $6.25 per hour. 1. What is the population mean? What is the best estimate of the population mean? 2. Develop a 99% confidence interval for the population mean wage (including benefits) for these psychiatrists. 3. How large a sample is needed to assess the population mean with an allowable error of$1.00 at 95% confidence?

Solutions

Expert Solution

1)

Population mean ( ) = sample mean () =65.00

The best estimate of a population mean is the sample mean.

The most fundamental point and interval estimation process involves the estimation of the population mean.

2)

Here using ti-83 calculator.

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