# Population and Sample Statistics

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For the following questions answer true or false for each

1. The mean for a sample of n=4 scores has a standard error of 5 points. This sample was selected from a population with a standard deviation of ơ=20.

2. The mean for a sample of n=16 scores has an expected value of 50. This sample was selected from a population with a mean of µ=50.

3. On average, a sample of n=16 scores from a population with ơ=10 will provide a better estimate of the population mean than you would get with a sample of n=16 scores from a population with ơ=5.

4. A sample is obtained from a population with ơ=12. If the sample mean has a standard error of 3, then the sample size is n=4.

5. A sample of n=16 scores is randomly selected from a population with µ=80 and ơ=16. If the sample mean is M=84, then the corresponding z-score is z=+1.00.

6. A sample of n=4 scores is selected from a population with µ=70 and ơ=10. The probability of obtaining a sample mean greater than 65 is p=0.8413.

7. The standard error of M provides a measure of the average distance between a sample mean and the population mean.

8. A sample mean with a z-score value greater than z=3.00 would be considered an extreme, unrepresentative sample.

9. A sample mean with a z-score value between -1.00 and +1.00 would be considered a fairly typical, representative sample.

10. A population has µ=60 and ơ=30. For a sample of n=25 scores from this population, a sample mean of M=55 would be considered an extreme value.

11. A population has µ=60 and ơ=10. For a sample of n=25 scores from this population, a sample mean of M=55 would be considered an extreme value.

#### Solution Preview

1. The mean for a sample of n=4 scores has a standard error of 5 points. This sample was selected from a population with a standard deviation of ơ=20.

False. This sample was selected from a population with a standard deviation of ơ=5*sqrt(4)=10

2. The mean for a sample of n=16 scores has an expected value of 50. This sample was selected from a population with a mean of µ=50.

True. Population mean and sample mean should be the same.

3. On average, a sample of n=16 scores from a population with ơ=10 will provide a better estimate of ...

#### Solution Summary

The solution gives detailed steps on answerting 11 true or false questions regarding on population and sample statistics. All questions are explained in details.