Question 1

A contractor wants to forecast the number of contracts in future quarters,using quarterly data on a number of contracts over the last 10 years.Which of the following would be the most appropriate analysis to perform?
A)Autoregressive modeling
B)One-way ANOVA
C)Least-squares forecasting with monthly or quarterly data
D)Two-way ANOVA

Accepted Answer

Since the contractor wants to forecast the number of contracts in future quarters, the most appropriate analysis to perform would be a forecasting model. One popular method for forecasting is least-squares, which can be done with monthly or quarterly data. Autoregressive modeling is a method for modeling time-series data, and one-way ANOVA and two-way ANOVA are methods for analyzing variance between groups. While these methods may be useful in other contexts, they are not appropriate for forecasting the number of contracts in future quarters.

Question 2

TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: 
-Referring to Table 17-1,which of the following values for the level of significance is the smallest for which at least two explanatory variables are significant individually?
A)0.01
B)0.025
C)0.05
D)0.15

Accepted Answer

The answer of TABLE 17-1
A real estate builder wishes to...

Question 3

The director of a training program wanted to know if a one-week orientation would change the perception of potential clients who would perceive the program as being good.He collected information on the number of clients who would rate the program as being good before and after the orientation.Which of the following tests will be the most appropriate? A)χ²test for proportions B)McNemar test C)Wilcoxon rank sum test D)Tukey-Kramer procedure

Accepted Answer

The McNemar test is appropriate for analyzing paired data where the same subjects are measured before and after an intervention. In this case, the director collected data on the number of clients who rated the program as good before and after the orientation, making the McNemar test the most appropriate choice. The other tests listed are not appropriate for this type of data.

Question 4

TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: 
-Referring to Table 17-1,which of the independent variables in the model are significant at the 5% level?
A)Income,Size,School
B)Income,Size
C)Size,School
D)Income,School

Accepted Answer

Looking at the "P-value" column, both Income and Size have p-values less than 0.05, indicating that they are statistically significant at the 5% level. However, School has a p-value greater than 0.05, indicating that it is not statistically significant and can be dropped from the model. Therefore, the best choice(s) are Income and Size.

Question 5

TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: 
-Referring to Table 17-1,which of the following values for the level of significance is the smallest for which every explanatory variable is significant individually?
A)0.01
B)0.025
C)0.05
D)0.15

Accepted Answer

The answer of TABLE 17-1
A real estate builder wishes to...

Question 6

The director of admissions at a state college is interested in seeing if admissions status (admitted,waiting list,denied admission)at his college is related to the type of community (urban,rural,suburban)in which an applicant resides.Which of the following tests will be the most appropriate? A)χ²test for independence B)Two-way ANOVA F test for the type of community effect C)Two-way ANOVA F test for interaction effect D)McNemar test

Accepted Answer

The χ² test for independence is appropriate for testing the association between two categorical variables, such as admissions status and type of community. The McNemar test is used to compare paired data and the two-way ANOVA F test is used to analyze the effects of two or more independent variables on a continuous dependent variable, which is not applicable in this scenario. Additionally, option C specifies an interaction effect, which is not mentioned in the question.

Question 7

The superintendent of a school district wanted to predict the percentage of students passing a sixth-grade proficiency test.She obtained the data on percentage of students passing the proficiency test (% Passing),daily mean of the percentage of students attending class (% Attendance),mean teacher salary in dollars (Salaries),and instructional spending per pupil in dollars (Spending)of 47 schools in the state.She believed that holding everything else constant,instructional spending per pupil had a positive but decreasing impact on percentage.Which of the following would be the most appropriate analysis to perform?
A)Autoregressive modeling
B)Exponential smoothing
C)Least-squares forecasting with monthly or quarterly data
D)Linear regression with log transformation

Accepted Answer

Linear regression with log transformation would allow for examining the relationship between the predictor variable (instructional spending per pupil) and the outcome variable (percentage of students passing the proficiency test) while accounting for the potential nonlinear relationship between the two variables. Additionally, using a log transformation on the predictor variable can help with interpreting the impact of changes in instructional spending per pupil on the percentage of students passing the proficiency test.

Question 8

Four surgical procedures currently are used to install pacemakers.If the patient does not need to return for follow-up surgery,the operation is called a "clear" operation.A heart center wants to compare the 4 procedures,and collects the following numbers of patients from their own records: Which of the following tests will be the most appropriate to find out which of the 4 procedures is the most effective? A)χ² test for difference in proportions B)Z test for difference in proportions C)One-way ANOVA F test for differences among more than two means D)The Marascuilo procedure

Accepted Answer

The answer of Four surgical procedures currently are used to...

Question 9

TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: 
-Referring to Table 17-1,what fraction of the variability in house size is explained by income,size of family,and education?
A)27.0%
B)33.4%
C)74.8%
D)86.5%

Accepted Answer

The R-squared value indicates the fraction of the variability in the dependent variable (in this case, house size) that is explained by the independent variables (income, family size, and education). In this case, the R-squared value is 0.748, which means that 74.8% of the variability in house size is explained by these three independent variables.

Question 10

A Paso Robles wine producer wanted to forecast the cases of Merlot wine sold.The number of cases of merlot wine sold in a 28-year period was collected.Which of the following would be the most appropriate analysis to perform?
A)The Marascuilo Procedure
B)The Tukey-Kramer Procedure
C)Least-squares forecasting with monthly or quarterly data
D)Moving averages modeling

Accepted Answer

The answer of A Paso Robles wine producer wanted to...

Question 11

TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: 
-Referring to Table 17-1,which of the following values for the level of significance is the smallest for which the regression model as a whole is significant?
A)0.0005
B)0.001
C)0.01
D)0.05

Accepted Answer

The smallest level of significance for which the regression model is significant is the one that is just below the p-value of the model. Since 0.0005 is the smallest option provided, it would be the smallest level of significance for which the model is significant.

Question 12

A manager of a product sales group believes the number of sales made by an employee depends on how many years that employee has been with the company and how he/she scored on a business aptitude test.A random sample of 38 employees was selected to collect data on their number of sales,number of years with the company and scores on a business aptitude test.Which of the following would you perform to draw a conclusion on the belief?
A)One-way ANOVA
B)Simple linear regression
C)Two-way ANOVA
D)Multiple linear regression

Accepted Answer

Multiple linear regression would be the best choice as it allows for the examination of the relationship between the number of sales and both the number of years with the company and the scores on the business aptitude test, while controlling for the potential effects of other variables. One-way ANOVA would only allow for the examination of the relationship between the number of sales and one variable (years with the company or aptitude test scores) at a time, while two-way ANOVA would allow for the examination of the relationship between the number of sales and both variables but would not control for the potential effects of other variables. Simple linear regression would only allow for the examination of the relationship between the number of sales and one variable (either years with the company or aptitude test scores) at a time.

Question 13

A political pollster randomly selects a sample of 100 voters each day for 8 successive days and asks how many will vote for the incumbent.The pollster wishes to see if the percentage favoring the incumbent candidate is too erratic.Which of the following would be the most appropriate analysis to perform?
A)Multiple linear regression
B)Exponential smoothing
C)Construct a p-chart
D)Perform a Levene's test

Accepted Answer

A p-chart is a statistical process control chart used to monitor the proportion of nonconforming units in a sample. In this case, the proportion of voters favoring the incumbent candidate can be considered the nonconforming units. By constructing a p-chart, the pollster can determine if the percentage favoring the incumbent candidate is within control limits or too erratic. Multiple linear regression and exponential smoothing are not appropriate for this scenario, as they are used for analyzing trends over time rather than monitoring proportions. Levene's test is used to test the homogeneity of variance in a set of data, which is not relevant to this scenario.

Question 14

A supplier of silicone sheets for producers of computer chips wants to evaluate her manufacturing process.She takes sample sizes of 5 from each day's output and counts the number of blemishes on each silicone sheet for 20 days consecutive days.Which of the following would be the most appropriate analysis to perform?
A)Autoregressive modeling
B)Exponential smoothing
C)Multiple linear regression
D)Construct a c chart

Accepted Answer

Since the supplier is counting the number of blemishes on each silicone sheet, a c chart would be appropriate to monitor the number of defects in the manufacturing process over time. A c chart is used for count data and evaluates whether the process is in control or not by comparing the number of blemishes per sample to established control limits.

Question 15

An investor wanted to forecast the price of a certain stock.He collected the mean daily price for the stock over the past 10 years.Which of the following would be the most appropriate analysis to perform?
A)The Marascuilo Procedure
B)The Tukey-Kramer Procedure
C)Least-squares forecasting with monthly or quarterly data
D)Autoregressive modeling

Accepted Answer

The best choice would be autoregressive modeling, as it is a method used specifically for time series data analysis, which is what the data on daily stock prices would fall under. The other options mentioned, such as the Marascuilo Procedure and Tukey-Kramer Procedure, are not appropriate for time series data analysis. Least-squares forecasting may be useful, but it would likely require more frequent data than monthly or quarterly to accurately predict daily stock prices.

Question 16

A Paso Robles wine producer wanted to forecast the cases of Merlot wine sold.The number of cases of merlot wine sold in a 28-year period was collected.Which of the following would be the most appropriate analysis to perform?
A)The Marascuilo Procedure
B)The Tukey-Kramer Procedure
C)Least-squares forecasting with monthly or quarterly data
D)Exponential smoothing modeling

Accepted Answer

Exponential smoothing modeling is a time series forecasting method that is particularly appropriate when the data has a trend, seasonality, or both. Since the number of cases of merlot wine sold was collected over a 28-year period, there is likely to be a trend and seasonality in the data. Therefore, exponential smoothing modeling would be the most appropriate analysis to perform. The Marascuilo Procedure and the Tukey-Kramer Procedure are not appropriate for time series forecasting, and least-squares forecasting with monthly or quarterly data may not account for seasonality.

Question 17

TABLE 17-1 A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: -Referring to Table 17-1,when the builder used a simple linear regression model with house size (House)as the dependent variable and education (School)as the independent variable,he obtained an r² value of 23.0%.What additional percentage of the total variation in house size has been explained by including family size and income in the multiple regression? A)2.8% B)51.8% C)72.6% D)74.8%

Accepted Answer

The R-squared value for the multiple regression model is 0.518 or 51.8%. This represents the additional percentage of the total variation in house size that is explained by including family size and income in the regression model.

Question 18

A certain type of rare gem serves as a status symbol for many of its owners.In theory,for low prices,the demand increases and it decreases as the price of the gem increases.However,experts hypothesize that when the gem is valued at very high prices,the demand increases with price due to the status owners believe they gain in obtaining the gem.Data on price and quantity sold were collected for a sample of 35 rare gems of this type.Which of the following would be the most appropriate analysis to perform?
A)Quadratic regression model
B)Exponential smoothing
C)Autoregressive modeling for trend fitting and forecasting
D)Least-squares forecasting with monthly or quarterly data

Accepted Answer

A quadratic regression model would allow for testing the hypothesis that demand increases with price, then decreases, and potentially increases again at very high prices. This model can also capture non-linear relationships between price and quantity sold.

Question 19

An economist is interested to see how consumption for an economy (in $ billions)is influenced by gross domestic product ($ billions)and aggregate price (consumer price index).Annual data from 30 years were collected.Which of the following would be the most appropriate analysis to perform?
A)Simple linear regression
B)Multiple linear regression
C)Exponential smoothing
D)Autoregressive modeling for trend fitting and forecasting

Accepted Answer

Since consumption is influenced by both GDP and aggregate price, it is necessary to perform a multiple linear regression analysis to examine the relationship and predictive power of these variables on consumption. Simple linear regression would not account for the influence of the second independent variable, while exponential smoothing and autoregressive models are not appropriate for analyzing the relationship between consumption, GDP, and aggregate price.

Question 20

Four surgical procedures currently are used to install pacemakers.If the patient does not need to return for follow-up surgery,the operation is called a "clear" operation.A heart center wants to compare the 4 procedures,and collects the following numbers of patients from their own records: Which of the following tests will be the most appropriate to find out whether the 4 procedures are equally effective? A)χ² test for difference in proportions B)Z test for difference in proportions C)One-way ANOVA F test for differences among more than two means D)McNemar test

Accepted Answer

The answer of Four surgical procedures currently are used to...

Quiz 17: A Roadmap for Analyzing Data

A contractor wants to forecast the number of contracts in future quarters,using quarterly data on a number of contracts over the last 10 years.Which of the following would be the most appropriate analysis to perform?

The director of admissions at a state college is interested in seeing if admissions status (admitted,waiting list,denied admission) at his college is related to the type of community (urban,rural,suburban) in which an applicant resides.Which of the following tests will be the most appropriate?

A Paso Robles wine producer wanted to forecast the cases of Merlot wine sold.The number of cases of merlot wine sold in a 28-year period was collected.Which of the following would be the most appropriate analysis to perform?

An investor wanted to forecast the price of a certain stock.He collected the mean daily price for the stock over the past 10 years.Which of the following would be the most appropriate analysis to perform?

A Paso Robles wine producer wanted to forecast the cases of Merlot wine sold.The number of cases of merlot wine sold in a 28-year period was collected.Which of the following would be the most appropriate analysis to perform?

An economist is interested to see how consumption for an economy (in $ billions) is influenced by gross domestic product ($ billions) and aggregate price (consumer price index) .Annual data from 30 years were collected.Which of the following would be the most appropriate analysis to perform?