Exam 7: Sampling and Sampling Distributions

The probability distribution of all possible values of the sample mean is

Consider a population of five families with the following data representing the number of pets in each family. a.Determine the mean and the variance of the population. b.There are ten possible samples of size 2 (sampling without replacement). List the 10 possible samples of size 2, and determine the mean of each sample. c.Using the ten sample mean values, compute the mean and the standard error of the mean.

The set of all elements of interest in a study is

A sample of 24 observations is taken from a population that has 150 elements. The sampling distribution of is

If we consider the simple random sampling process as an experiment, the sample mean is

From a population of 200 elements, a sample of 49 elements is selected. It is determined that the sample mean is 56 and the sample standard deviation is 14. The standard error of the mean is

A probability distribution for all possible values of a sample statistic is known as

A sample statistic, such as a sample mean, is known as

The sampling error is the

A new soft drink is being market tested. It is estimated that 60% of consumers will like the new drink. A sample of 96 taste tested the new drink. a.Determine the standard error of the proportion b.What is the probability that more than 70.4% of consumers will indicate they like the drink? c.What is the probability that more than 30% of consumers will indicate they do not like the drink?

The average weekly earnings of bus drivers in a city are $950 (that is $\mu$ ) with a standard deviation of $45 (that is $\sigma$ ). Assume that we select a random sample of 81 bus drivers. a.Compute the standard error of the mean. b.What is the probability that the sample mean will be greater than $960? c.If the population of bus drivers consisted of 400 drivers, what would be the standard error of the mean?

The sample statistic, such as , s, or , that provides the point estimate of the population parameter is known as

Below you are given the values obtained from a random sample of 4 observations taken from an infinite population. a.Find a point estimate for $\mu$ . Is this an unbiased estimate of $\mu$ ? Explain. b.Find a point estimate for $\sigma$ ². Is this an unbiased estimate of $\sigma$ ²? Explain. c.Find a point estimate for $\sigma$ . d.What can be said about the sampling distribution of ? Be sure to discuss the expected value, the standard deviation, and the shape of the sampling distribution of 11ecf06b_be84_96e5_b512_aff0a4e65f1e_TB2075_11 .

A department store has determined that 25% of all their sales are credit sales. A random sample of 75 sales is selected. a.What is the probability that the sample proportion will be greater than 0.34? b.What is the probability that the sample proportion will be between 0.196 and 0.354? c.What is the probability that the sample proportion will be less than 0.25? d.What is the probability that the sample proportion will be less than 0.10?

There are 500 employees in a firm, 45% are female. A sample of 60 employees is selected randomly. a.Determine the standard error of the proportion. b.What is the probability that the sample proportion (proportion of females) is between 0.40 and 0.55?

A population consists of 8 items. The number of different simple random samples of size 3 that can be selected from this population is

The SAT scores have an average of 1200 with a standard deviation of 60. A sample of 36 scores is selected. a.What is the probability that the sample mean will be larger than 1224? b.What is the probability that the sample mean will be less than 1230? c.What is the probability that the sample mean will be between 1200 and 1214? d.What is the probability that the sample mean will be greater than 1200? e. What is the probability that the sample mean will be larger than 73.46?

From a group of 12 students, we want to select a random sample of 4 students to serve on a university committee. How many different random samples of 4 students can be selected?

As the sample size becomes larger, the sampling distribution of the sample mean approaches a

Four hundred people were asked whether gun laws should be more stringent. Three hundred said "yes," and 100 said "no." The point estimate of the proportion in the population who will respond "no" is