Business Statistics in Practice: Using Data, Modeling, and Analytics 8th Edition

When testing a hypothesis about a single mean, if the sample size is 20, the population standard deviation is unknown, and the population is assumed to be a normal distribution, the correct test statistic to use is ___________. A. r B. z C. t D. p-value Answer: C. Answer: C. Answer:

Data summarized in a frequency distribution or histogram form are often called weighted data. Answer: FALSEData summarized in a frequency distribution or histogram form are called grouped data. Answer: FALSEData summarized in a frequency distribution or histogram form are called grouped data. Answer: FALSE Data summarized in a frequency distribution or histogram form are

A confidence interval for the population mean is meant to contain a specified percentage of the individual population measurements. Answer: FALSEThis is the definition of a tolerance interval. A confidence interval is the level of confidence we have that the population mean is in the interval. Answer: FALSEThis is the definition of

In systematic sampling, the first element is randomly selected from the first (N/n) elements. Answer: TRUE Answer: TRUE Answer: TRUE The population mean is the average of the population measurements. Answer: TRUE Answer: TRUE Answer: TRUE We are testing H0: .95; versus HA: > .95. When = .99, s =

A graphical portrayal of a quantitative data set that divides the data into classes and gives the frequency of each class is a(n) ___________. A. ogive plot B. dot plot C. histogram D. Pareto chart E. bar chart Answer: C. Answer: C. Answer: C. During the past six months, 73.2 percent of US households purchased

If = .0139 and 25 shipments of 20 items each were examined, what are the UCL and the LCL for the p chart? A. [.0118, .0159] B. [0, .0401] C. [.008, .0198] D. [0, .0924] Answer: D. Answer: D. Answer: D. Joe is considering pursuing an MBA degree. He has applied to two different

Which one of the following tools is not used to check the normality of residuals assumption for a multiple regression model? A. histogram B. stem-and-leaf display C. scatter diagram D. normal plot Answer: C. Answer: C. Answer: C. A control chart on which the proportions of nonconforming units in subgroups of size n are

The demand for a product for the last six years has been 15, 15, 17, 18, 20, and 19. The manager wants to predict the demand for this time series using the following simple linear trend equation: trt = 12 + 2t. Use this equation to forecast the demand for

X has the following probability distribution P(X). Compute the variance value of X. A. 1.58 B. .955 C. .912 D. .625 Answer: C. Answer: C. Answer: C. The U.S. Department of Health and Human Services collected sample data for 772 males between the ages of 18 and 24. That sample group has a mean

Using either the critical value rule or the p-value rule, if a one-sided null hypothesis is rejected at a given significance level, then the corresponding two-sided null hypothesis (i.e., the same sample size, the same standard deviation, and the same mean) will ______________ be rejected at the same significance level. A.

A survey of the wine market has shown that the preferred wine for 17 percent of Americans is merlot. A wine producer in California, where merlot is produced, believes the figure is higher in California. She contacts a random sample of 550 California residents and asks which wine they purchase

If events A and B are mutually exclusive, then P(A|B) is always equal to zero. Answer: TRUE Answer: TRUE Answer: TRUE The binomial experiment consists of n independent, identical trials, each of which results in either success or failure and is such that the probability of success on any trial

____________ theory is a methodology that attempts to determine the number of servers that strikes an optimum balance between the time customers wait for service and the cost of providing service. A. Exponential B. Binomial C. Uniform distribution D. Queuing Answer: D. Answer: D. Answer: D. A random sample of size 1,000 is taken

In determining the sample size to estimate a population proportion, as p approaches .5, the calculated value of the sample size ______________. A. stays the same B. decreases C. increases Answer: C. Answer: C. Answer: C. The EPA has stipulated that the Pollution Standard Index (PSI) for clean air standards is to average no

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m.). They selected 13 patrons and had them get in line between 2 and 3 p.m. Each was given a stopwatch to record the time they spent

The requirement that the probability of success remains constant from trial to trial is a property of the _________________ distribution. A. binomial B. uniform C. normal D. Poisson Answer: A. Answer: A. Answer: A. Using the p-value rule, if a null hypothesis is not rejected at a significance level of .05, it will _____________

A fair die is rolled 10 times. What is the probability that an even number (2, 4, or 6) will occur between 2 and 4 times? A. .6123 B. .1709 C. .1611 D. .3662 E. .3223 Answer: D. P(X) = n!/[x!(n x)!] px(1 p)nx, for x = 2, 4, 6; or look up in binomial table,

If the population from which we sample is highly skewed to the right or to the left, then the population _________ might be a better measure of central tendency than the population mean. A. median B. variance C. mode D. average Answer: A. Answer: A. Answer: A. A random sample of size 1,000 is

The ____________ hypothesis is not rejected unless there is sufficient sample evidence to do so. A. research B. alternative C. null D. true Answer: C. Answer: C. Answer: C. A random sample of 11 third-year medical school students took a comprehensive written exam as well as a comprehensive oral exam. The scores on both

The mean of the binomial distribution is equal to A. p. B. np. C. px(1 p)nx. D. (n)(p)(1 p). E. Answer: B. Answer: B. Answer: B. After plotting the data points on a scatter diagram, we have observed an inverse relationship between the independent variable (X) and the dependent variable (Y). Therefore, we can expect

The J.O. Supplies Company buys calculators from a non-US supplier. The probability of a defective calculator is 10 percent. If 10 calculators are selected at random, what is the probability that 3 or more of the calculators will be defective? A. .0702 B. .2639 C. .0016 D. 0 Answer: A.P(X 3) = 1 P(X

In an observational study, the variable of interest is called a response variable. Answer: TRUE Answer: TRUE Answer: TRUE It can be established at = .05 that a majority of students favor the plus/minus grading system at a university if in a random sample of 500 students, 270 favor the

If the number of surface nonconformities on a specific size of a metal piece is the discrete random variable in question, then the appropriate probability distribution that can describe the probability of a specific size metal sheet containing 3 nonconformities is most likely given by the binomial distribution. Answer: FALSEThis example

When using a completely randomized design (one-way analysis of variance), the calculated F statistic will decrease as A. the variability among the groups decreases relative to the variability within the groups. B. the total variability increases. C. the total variability decreases. D. the variability among the groups increases relative to the variability within the

Employees of a local university have been classified according to gender and job type. If an employee is selected at random, what is the probability that the employee is a member of the hourly staff, given that the employee is female? A. 0.400 B. 0.133 C. 0.160 D. 0.053 E. 0.533 Answer: A. Answer: A. Answer:

The cashier service time at the local branch of the Rivertown bank has an exponential distribution with a mean of 2.5 minutes. What is the probability that the service time exceeds 3 minutes? A. .3012 B. .6988 C. .4346 D. .5654 E. .0821 Answer: A. Answer: A. Answer: A. How well a process is able