QNT 275 FINAL EXAM

QNT 275 FINAL EXAM 26/30 for a 87% A researcher wants to test if the mean annual salary of all lawyers in a city is different than $110,000. The null hypothesis for this example will be that the population mean is: • equal to $110,000 A sample of 16 from a population produced a mean of 86.9 and a standard deviation of 14.3. A sample of 18 from another population produced a mean of 75.4 and a standard deviation of 15.9. Assume that the two populations are normally distributed and the standard deviations of the two populations are equal. The null hypothesis is that the two population means are equal, while the alternative hypothesis is that the mean of the first population is greater than the man of the second population. The significance level is 1%. What is the critical value of t for the hypothesis test? 2.449 In a hypothesis test, a Type I error occurs when: a true null hypothesis is rejected A continuous random variable x has a right-skewed distribution with a mean of 80 and a standard deviation of 12. The sampling distribution of the sample mean for a sample of 50 elements taken from this population is: skewed to the right A quantitative variable is the only type of variable that can: assume numeric values for which arithmetic operations make sense If you divide the number of elements in a sample with a specific characteristic by the total number of elements in the sample, the dividend is the: sample mean An error that occurs because of chance is called: sampling error The regression model y = A + Bx + e is: an exact relationship In a one-way ANOVA, we analyze only one: variable Two events are independent if the occurrence of one event: does not affect the probability of the occurrence of the other event. For small degrees of freedom, the chi-square distribution is: skewed to the right Two paired or matched samples would imply that: two data values are collected from the same source (elements) for two dependent samples In a survey regarding job satisfaction, 574 in a sample of 934 female job-holders stated that they are satisfied with their jobs, while 500 in a sample of 755 male job-holders stated that they are satisfied with their jobs. The null hypothesis is that the proportions of all female and male job-holders who are satisfied with their jobs are the same. The alternative hypothesis is that the proportion of female job-holders who are satisfied with their jobs is lower than the proportion of male job-holders stated who are satisfied with their jobs. The significance level is 2.5%. What is the critical value of z for the hypothesis test? -1.96 Which of the following assumptions is not required to use ANOVA? All samples are of the same size. For a goodness-of-fit test, the frequencies obtained from the performance of an experiment are the: observed frequencies For a one-tailed test, the p-value is: the area under the curve to the same side of the value of the sample statistic as is specified in the alternative hypothesis A researcher wants to test if elementary school children spend less than 30 minutes per day on homework. The alternative hypothesis for this example will be that the population mean is: less than 30 minutes You toss a coin nine times and observe 3 heads and 6 tails. This event is a: simple event The p-value is the: smallest significance level at which the null hypothesis can be rejected In a hypothesis test, a Type II error occurs when: a false null hypothesis is not rejected Which of the following pairs of events are mutually exclusive? Female and male A qualitative variable is the only type of variable that: cannot be measured numerically We can use the analysis of variance procedure to test hypotheses about: two or more population means A linear regression: gives a relationship between two variables that can be described by a line The alternative hypothesis is a claim about a: parameter, where the claim is assumed to be true if the null hypothesis is declared false The mean of a discrete random variable is its: expected value The mean of a discrete random variable is the mean of its: probability distribution To make tests of hypotheses about more than two population means, we use the: analysis of variance distribution The model y = A + Bx is a: deterministic model In a game of four-handed Hearts, all 52 cards of a standard deck are dealt, so that each player starts each round with 13 cards in a hand. Suppose player A's hand has three clubs, six diamonds, two hearts, and two spades. What is the relative frequency of spades, rounded to two decimal places, dealt to player A? 0.15