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A simple randoes sample is taken from a population and yields the following data for a variable of the population:

find a point estimate for the population standard deviation (i.e., the standard deviation of the variable).

Short Answer

Expert verified

The point estimate for the population standard deviation is 9.72

Step by step solution

01

Step 1:Given Information

02

Step 2:Calculation

The mean of the variable is:

x¯=xnn=9+32+37+32+20+24+10+15+21+3010=23010=23

Now,

The formula for sample standard deviation is given below:

s=xi-x¯2n-1

Calculating

xi-x¯2

03

Step 3:Calculation (b)

Substituting 850 for(x-x)2

in the sampie standard deviation formulae

s=85010=94,4444=9.72

Thus, the point estimate for the population standard deviation is 9.72

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Most popular questions from this chapter

A confidence interval for a population mean has a margin of error of 0.047

a. Determine the length of the confidence interval.

b. If the sample mean is 0.205, obtain the confidence interval.

c. Construct a graph that illustrates your results.

Formula 8.2on page 327provides a method for computing the sample size required to obtain a confidence interval with a specified confidence level and margin of error. The number resulting from the formula should be rounded up to the nearest whole number.

a. Why do we want a whole number?

b. Why do we round up instead of down?

Identify the formula for the margin of error for the estimate of a population mean when the population standard deviation is unknown.

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b. Interpret your result in part (a).

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