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QNT 561 final quiz 1) In a set of observations, which measure of central tendency reports the value that occurs most often? Geometric mean A. Mean B. Median C. Mode D. 2) Which of the following measures of central location is affected most by extreme values? Geometric mean A. Median B. Mean C. Mode D. 3) A difference between calculating the sample mean and the population mean is: There are no differences. A. Only in the symbols, we use instead of µ and n instead of N. B. We divide the sum of the observations by n - 1 instead of n C. The observations are ranked and select the middle value for the population mean. D. 4) The difference between a random variable and a probability distribution is: A random variable does not include the probability of an event. A. A random variable can only assume whole numbers. B. A probability distribution can only assume whole numbers. C. None of the above. D. 5) Which of the following is not a requirement of a binomial distribution? Equally likely outcomes. A. A constant probability of success. B. Only two possible outcomes. C. A fixed number of trails. D. 6) Which of the following is not a requirement of a probability distribution? The probability of each outcome is between 0 and 1. A. The outcomes are mutually exclusive. B. Equally likely probability of a success. C. Sum of the possible outcomes is 1.00. D. 7) A sample Is part of the population. A. Has more than 30 observations. B. Is usually identified as N. C. All of these D. 8) The difference between the sample mean and the population mean is called the Sampling error. A. Standard error of the mean. B. Population mean. C. D. Population standard deviation. 9) Suppose a population consisted of 20 items. How many different samples of n = 3 are possible? 120 A. 20 B. 6840 C. 1140 D. 10) Which of the following statements is not a characteristic of the t distribution? Like z there is only one t distribution. A. It is symmetrical. B. It is a continuous distribution. C. It has a mean of 0. D. 11) We wish to develop a confidence interval for the population mean. The population follows the normal distribution, the standard deviation of the population is 3, and we have a sample of 10 observations. We decide to use the 90% level of confidence. The appropriate value of to represent the level of confidence is t=1.812 A. t=1.833 B. C. D. z =1.65 z=1.96 12) We wish to develop a confidence interval for the population mean. The shape of the population is not known, but we have a sample of 40 observations. We decide to use the 92% level of confidence. The appropriate value of z is: 1.75 A. 2.58 B. 1.96 C. 1.65 D. 13) The Special Rule of Addition is used to combine Events based on subjective probabilities A. Mutually exclusive events B. Independent events. C. Events that total more than one. D. 14) We use the General Rule of Multiplication to combine Events based on subjective probabilities A. Mutually exclusive events. B. Events that are not independent. C. Events that total more than 1.00. D. 15) Which of the following is not a type of probability? Classical A. Independent B. Subjective C. Relative frequency D. 16) Which of the following statements is true regarding a sample? It is a part of population. A. It must contain at least five observations. B. It refers to descriptive statistics C. All of these are correct D. 17) A discrete variable is Cannot be negative. A. Can assume only whole number values. B. An example of a qualitative variable. C. Can assume only certain clearly separated values D. 18) The ratio scale of measurement Is usually based on counting. A. Cannot assume negative values. B. Usually involves ranking. C. Has a meaningful zero point. D. 19) In a two-sample test of means for independent samples, the equal sign always appears in The null hypothesis. A. The alternate hypothesis. B. The upper tail of the test statistic. C. D. None of these 20) Which of the following is a requirement for a two-sample test of proportions. nB and n(1-B) are both greater than 5. A. Both populations are positively skewed. B. The population standard deviations are equal. C. Both samples are at least 30. D. 21) The alternate hypothesis None of these A. Is accepted if the null hypothesis is rejected. B. C. D. Will always contain the equal sign. Tells the value of the sample mean. 22) To conduct a nonparametric test the. The data must be at least interval scale. A. Population must follow the normal distribution. B. The standard deviation must be known. C. It is not necessary to make any assumption about the shape of the population. D. 23) Which of the following is not a characteristic of the X2 It approaches a normal distribution as the degrees of freedom increase. A. Its shape is based on the sample size. B. It is not negative. C. It is positively skewed. D. 24) In a goodness-of-fit test where the sample size is 200, there are 5 categories, and the significance level is .05. The critical value of X2 is 9.488 A. 11.070 B. 43.773 C. None of these D. 25) In the ANOVA table the value of k is The sum of squares total. A. The number of independent variables. B. The total number of observations C. D. The number of degrees of freedom. 26) A correlation matrix Reports the multiple regression equation. A. Shows all simple coefficients of correlation. B. Shows all possible net regression coefficients. C. Shows the correlations that are positive. D. 27) A dummy variable or indicator variable Is equal to Y A. May assume only a value of 0 or 1. B. Is another term for the dependent variable. C. Is found by (Y - Y). D.