The sample mean is a consistent estimator of the population mean because the:（）
A. expected value of the sample mean is equal to the population mean.
B. sampling distribution of the sample mean has the smallest variance of any other unbiased estimators of the population mean.
C. sample mean provides a more accurate estimate of the population mean as the sample size increases.
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If a smooth curve is to represent a probability density function, what two requirements must be satisfied The :（）
A. area under the curve must be zero and the curve must not fall below the horizontal axis.
B. area under the curve must be one and the curve must not rise above the horizontal axis.
C. total area under the curve must be one and the curve must not fall below the horizontal axis.
Which of the following random variables would be most likely to follow a discrete uniform distribution（）
A. The outcome of the roll of two standard, six - sided dice where X is the sum of the numbers facing up.
B. The number of heads on the flip of two coins.
C. The outcome of a roll of a standard, six - sided die where X equals the number facing up on the die.
An analyst wants to get, crate a simple random sample of 500 stocks from all 10000 stocks traded on the New York Stock Exchange, the American Stock Exchange, and NASDAQ. Which of the following methods is least likely to generate a random sample（）
A. Listing all the stocks traded on all three exchanges in alphabetical order and selecting every. 20th stock.
B. Writing the name of each stock on a piece of paper, putting them in a hat, and drawing out 500 names, one at a time.
C. Using the 500 stocks in the S＆P 500.
Which of the following statements about sampling errors is FALSE（）
A. Sampling errors are errors due to the wrong sample being selected from the population.
B. Sampling error is the difference between a sample statistic and its corresponding population parameter.
C. Sampling errors will vary from one sample to the next.
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