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Determine the point estimate of the population mean and margin of error for each confidence interval. Lower bound: \(5,\) upper bound: 23

Short Answer

Expert verified
Point Estimate: 14, Margin of Error: 9

Step by step solution

01

Find the Point Estimate

The point estimate of the population mean is the midpoint of the confidence interval. To find this, add the lower and upper bounds, then divide by 2.Point Estimate = \(\frac{5 + 23}{2}\).
02

Calculate the Point Estimate

Perform the calculation from Step 1 to determine the point estimate:\(\frac{5 + 23}{2} = \frac{28}{2} = 14\).
03

Find the Margin of Error

The margin of error is half the width of the confidence interval. To find this, subtract the lower bound from the upper bound, then divide by 2.Margin of Error = \(\frac{23 - 5}{2}\).
04

Calculate the Margin of Error

Perform the calculation from Step 3 to determine the margin of error:\(\frac{23 - 5}{2} = \frac{18}{2} = 9\).

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Point Estimate
In statistics, a point estimate is a single value used to approximate a population parameter. In the context of the given exercise, the point estimate refers to the estimated population mean, which is calculated as the midpoint of the confidence interval. To compute this for the given interval \(5, 23\), simply add the lower bound (5) and the upper bound (23), then divide by 2. The formula is as follows:

\(\text{Point Estimate} = \frac{5 + 23}{2} = 14\)

This value gives us a specific number, which is our best guess of the true population mean based on the sample data.
Margin of Error
The margin of error represents the maximum expected difference between the point estimate and the actual population mean. It indicates the range within which we can expect the true population mean to lie with a certain level of confidence. To find the margin of error for the given interval ([5, 23]), you subtract the lower bound from the upper bound and then divide by 2:

\(\text{Margin of Error} = \frac{23 - 5}{2} = 9\)

In this case, the margin of error is 9. This means we are confident that our point estimate (14) is within 9 units of the true population mean.
Population Mean
The population mean is the average of a set of data points from an entire population. Unlike a sample mean, which only uses data from a subset of the population, the population mean encompasses all members of the population. In practice, it is often impractical or impossible to calculate the population mean for large populations, so a point estimate along with a margin of error is used. By constructing a confidence interval, we can estimate the population mean and understand how precise that estimate is. With our point estimate of 14 and a margin of error of 9, we are suggesting that the true population mean is likely between 5 and 23 with a certain level of confidence, often 95%.

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Most popular questions from this chapter

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