Exam 7: Probability and Samples: The Distribution of Sample Means.

A sample of n = 4 scores is selected from a population with μ = 40 with σ = 8,and the sample mean is M = 43.What is the expected value for the sample mean?

Samples of size n = 9 are selected from a population with μ = 80 with σ = 18.What is the expected value for the distribution of sample means?

A sample is selected from a population with µ = 30 and σ = 10.If the sample mean of M = 34 corresponds to z = +2.00,then the sample size is n = 25.

In order for the distribution of sample means to be normal,it must be based on samples of at least n = 30 scores.

A sample of n = 4 scores is selected from a population with μ = 50 and σ = 12.If the sample mean is M = 56,what is the z-score for this sample mean?

On average,a sample of n = 16 scores will provide a better estimate of the population mean than you would get with a sample of n = 9 scores from the same population.

Find the z-score for the sample mean for each of the following samples obtained from a population with µ = 50 and σ = 12. A)M = 56 for a sample of n = 4 B)M = 42 for a sample of n = 9 C)M = 51 for a sample of n = 36

A sample of n = 4 scores is obtained from a population with μ = 70 and σ = 8.If the sample mean corresponds to a z-score of 2.00,what is the value of the sample mean?

A sample of n = 25 scores is selected from a population with μ = 70 and σ = 20.It is very unlikely that the sample mean will be greater than 72.

Which combination of factors will produce the largest value for the standard error?

A sample of n = 4 scores is selected from a normal population with a mean of µ = 50 and a standard deviation of σ = 20.What is the probability of obtaining a sample mean greater than M = 48?

A sample of n = 25 scores is selected from a population with a mean of µ = 80 and a standard deviation of σ = 20.The standard error for the sample mean is 20.

For a population with µ = 80 and σ = 20,the distribution of sample means based on n = 16 will have an expected value of ____ and a standard error of ____.

A sample of n = 9 scores is randomly selected from a population with µ = 80 and ? = 9.If the sample mean is M = 83,then the corresponding z-score is z = +3.00.

If random samples,each with n = 9 scores,are selected from a normal population with µ = 80 and σ = 18,how much difference,on average,should there be between a sample mean and the population mean?

A sample of n = 36 scores is selected from a population with σ = 12.If the sample mean of M = 56 produces a z-score of z = +3.00,then what is the population mean?

If the sample size is equal to the population variance (n = σ²),then the standard error is equal to 1.

If a sample of n = 4 scores is obtained from a population with μ = 70 and σ = 12,what is the z-score corresponding to a sample mean of M = 73?

A sample obtained from a population with σ = 12 has a standard error of 2 points.How many scores are in the sample?

For a normal population with µ = 40 and σ = 10,which of the following samples has the highest probability of being obtained?