complete 100% correct answers
Doubling the size of the sample will - Correct Answers reduce the standard error of the
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mean
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The sample mean is the point estimator of - Correct Answers U
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A simple random sample of size n from an infinite population of size N is to be selected. Each
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possible sample should have - Correct Answers the same probability of being selected
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Which of the following statements regarding the sampling distribution of sample means is
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incorrect? - Correct Answers The standard deviation of the sampling distribution is the
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standard deviation of the population.
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A simple random sample of size n from an infinite population is a sample selected such that -
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Correct Answers each element is selected independently and is selected from the same
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population
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The fact that the sampling distribution of sample means can be approximated by a normal
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probability distribution whenever the sample size becomes large is based on the - Correct
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Answers central limit theorem.
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Cluster sampling is - Correct Answers a probability sampling method.
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The central limit theorem states that - Correct Answers if the sample size n is large, then
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the sampling distribution of the sample mean can be approximated by a normal distribution.
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The value of the _____ is used to estimate the value of the population parameter - Correct
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Answers sample statistic
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The sampling distribution of is the - Correct Answers probability distribution of all possible
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I values of the sample proportion.
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Which of the following is not a symbol for a parameter? - Correct Answers S.
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The sample statistic characteristic s is the point estimator of - Correct Answers σ..
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The distribution of values taken by a statistic in all possible samples of the same size from
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the same population is called a - Correct Answers sampling distribution.
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Which of the following is a point estimator? - Correct Answers S.
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,As a rule of thumb, the sampling distribution of the sample proportion can be approximated
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by a normal probability distribution when - Correct Answers n(1 - p) ≥ 5 and np ≥ 5.
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A sample of 92 observations is taken from an infinite population. The sampling distribution
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of is approximately - Correct Answers normal because of the central limit theorem.
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The central limit theorem is important in Statistics because it enables reasonably accurate
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probabilities to be determined for events involving the sample average - Correct Answers
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when the sample size is large regardless of the distribution of the variable.
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The distribution of values taken by a statistic in all possible samples of the same size from
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the same population is the sampling distribution of - Correct Answers The sample
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Which of these best describes a sampling distribution of a statistic? - Correct Answers It is
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the distribution of all of the statistics calculated from all possible samples of the same
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sample size.
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The probability distribution of all possible values of the sample proportion is the - Correct
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Answers sampling distribution of p.
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For a fixed confidence level and population standard deviation, if we would like to cut our
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margin of error in half, we should take a sample size that is - Correct Answers four times as
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large as the original sample size.
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We can reduce the margin of error in an interval estimate of p by doing any of the following
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except - Correct Answers increasing the planning value p* to .5.
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When computing the sample size needed to estimate a proportion within a given margin of
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error for a specific confidence level, what planning value of p should be used when no
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estimate of p is available? - Correct Answers 0.50
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A statistics teacher started class one day by drawing the names of 10 students out of a hat
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and asked them to do as many pushups as they could. The 10 randomly selected students
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averaged 15 pushups per person with a standard deviation of 9 pushups. Suppose the
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distribution of the population of number of pushups that can be done is approximately
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normal. Which of the following statements is true? - Correct Answers A t distribution should
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be used because σ is unknown.
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The z value for a 99% confidence interval estimation is - Correct Answers 2.58
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In an interval estimation for a proportion of a population, the critical value of z at 99%
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confidence is - Correct Answers 2.576.
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In interval estimation, as the sample size becomes larger, the interval estimate - Correct
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Answers becomes narrower.In general, higher confidence levels provide larger
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confidence intervals.
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, One way to have high confidence and a small margin of error is to - Correct Answers
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increase the sample size.
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From a population that is normally distributed, a sample of 30 elements is selected and the
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standard deviation of the sample is computed. For the interval estimation of μ, the proper
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distribution to use is the - Correct Answers t distribution with 29 degrees of freedom.
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As the number of degrees of freedom for a t distribution increases, the difference between
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the t distribution and the standard normal distribution - Correct Answers becomes smaller.
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The value added and subtracted from a point estimate in order to develop an interval
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estimate of the population parameter is known as the - Correct Answers margin of error.
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What is the symbol for the population mean? If the population follows a normal distribution,
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the confidence interval is _____ and can be used for any sample size. If the population does
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not follow a normal distribution, the confidence interval will be _____. Which of the following
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choices correctly complete this statement? - Correct Answers exact; approximate.
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The t value for a 99% confidence interval estimation based upon a sample of size 10 is -
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Correct Answers 3.250.
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To compute the necessary sample size for an interval estimate of a population proportion,
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all of the following procedures are recommended when p is unknown except - Correct
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Answers using .95 as an estimate.
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Using an α = .04, a confidence interval for a population proportion is determined to be .65 to
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.75. If the level of significance is decreased, the interval for the population proportion -
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Correct Answers becomes wider.
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For a fixed confidence level and population standard deviation, if we would like to cut our
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margin of error to 1/3 of the original size, we should take a sample size that is - Correct
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Answers nine times as large as the original sample size.
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The sampling distribution of can be approximated by a normal distribution as long as -
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Correct Answers np> 5 and n(1-p)>5 greater or equals.
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When "s" is used to estimate "σ," the margin of error is computed by using the - Correct
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Answers t distribution.
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The margin of error in an interval estimate of the population mean is a function of all of the
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following except the - Correct Answers sample mean.
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For a fixed sample size, n, in order to have a higher degree of confidence, the margin of error
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and the width of the interval - Correct Answers must be larger.
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