Analytics Final Exam Flashcards
A real estate developer has data on several financial variables for each quarter from 1995 to 2001. The variables are housing starts (in thousands), the housing price index (a measure of average housing selling prices), unemployment rate, average disposable income, and home owner vacancy rates. A partial view of the data set containing the 80 observations is given below.
In order to create a regression model to analyze the relationship between housing starts and the other housing-related and macro-economic variables, which cell references should be entered?
- Input Y Range: A1:B81 Input X Range: C1:F81
- Input Y Range: B1:F81 Input X Range: A1:A81
- Input Y Range: B1:F81 Input X Range: A1:A81
- Input Y Range: B1:B81 Input X Range: C1:F81

- Input Y Range: B1:B81 Input X Range: C1:F81
Suppose we want to assign dummy variables to the seasons (Winter, Spring, Summer, Fall). How many dummy variables do we need?
- 1
- 2
- 3
- 4
1
A real estate developer has data on a number of U.S. National financial variables for each quarter from 1995 to 2001. The variables are housing starts (in thousands), the housing price index (a measure of average housing selling prices), unemployment rate, average disposable income, and home owner vacancy rates. A partial view of the data is below.
If the developer wanted to create a regression model to predict housing starts from all the other financial variables, which of the following would be INDEPENDENT variables? (Select all that apply.)
- Year and Quarter
- Housing Starts (thousands)
- House Price Index
- Unemployment Rate
- Disposable Income
- Home Owner Vacancy Rates

House Price Index
Unemployment Rate
Disposable Income
Home Owner Vacancy Rates
A restaurant supply manager analyzes the relationship between a restaurant’s location and the number of meals consumed by comparing clients in two locations: Munich and Paris. The manager’s first regression model uses the number of meals consumed as the dependent variable and a dummy variable for location (Munich or Paris) as an independent variable. This model has an R-squared of 0.712, and the coefficient for location is statistically significant.
The manager runs a second model, adding another variable, the amount of wine consumed with meal. In this model, the coefficient for location is no longer significant, the R-squared has increased from 0.712 to 0.719, and the adjusted R-squared has decreased. Which of the following is the most likely reason for this pattern of changes?
- The owner made a mistake; it is impossible for a once significant variable to no longer be significant.
- The variables for location and wine consumption are collinear.
- The variable for location is a better predictor than wine consumption.
- Neither location nor wine consumption is a good predictor in the model.
The variables for location and wine consumption are collinear.
How would you describe the shape of the distribution shown below?
- Uniform
- Right-tailed
- Left-tailed
- Symmetric

Right-tailed
How many houses cost more than $200 thousand and less than or equal to $800 thousand?
- Approximately 11
- Approximately 15
- Approximately 22
- Approximately 25

22
A manager examines the histogram below and, after conducting additional research, finds that the observation in bin 3 is an input error and should have been entered as 13. If the histogram is updated with the correct number, which of the following will occur?
- The mean will decrease.
- The mode will increase.
- The median will increase.
- The standard deviation will decrease.

The standard deviation will decrease.
Which of the following Excel formulas or tools would correctly calculate the average hourly hot dog sales over a two-day period from the data shown below? SELECT ALL THAT APPLY.
- The Descriptive Statistics tool
- AVERAGE(B2:B17)
- AVERAGEIF(B2:B17)
- MEAN(B2:B17)
- MEDIAN(B2:B17)
- MODE.SNGL(B2:B17)
- SUM(B2:B17)/COUNT(B2:B17)

- The Descriptive Statistics tool
- AVERAGE(B2:B17)
- SUM(B2:B17)/COUNT(B2:B17)
If the variance of a data set is 486.75, what is the standard deviation?
Please give your answer rounded to 2 digits to the right of the decimal point. That is, if you think the answer is 486.750101, you should enter 486.75. [Fill in the blank]
[Blank]
22.06
The scatterplot below shows the temperature and the amount of hot chocolate sold for sixteen randomly selected days in a coffee shop in Boston. What is the most likely correlation between temperature and hot chocolate sold?
- -.8
- -.2
- .2
- .8

-.8
The spreadsheet below contains data for 30 students’ grades and the number of hours each student spent studying. What formula would give the correlation between hours studying and quiz grades?
- CORREL(A1:A30, B1:B30)
- CORREL(A1,A30, B1,B30)
- CORREL(A2:A31, B2:B31)
- CORREL(A2,A31, B2,B31)

CORREL(A2:A31, B2:B31)
A real estate firm wants to calculate percentiles for the prices of 25 houses it has listed. If the prices are listed in cells A2:A26, which of the following Excel functions would calculate the 95th percentile?
- PERCENTILE.INC(A2:A26,0.05)
- PERCENTILE.INC(A2:A26,0.95)
- PERCENTILE.INC(A2:A26,0.025)
- PERCENTILE.INC(A2:A26,0.975)
PERCENTILE.INC(A2:A26,0.95)
The scatter plot below shows the home sales of an independent real estate broker over several years. Approximately how many more homes did the broker sell in 2014 than in 2012?
- 5
- 10
- 15
- 20

10
Which of the following questions are biased? SELECT ALL THAT APPLY.
- How much more important is location than price when purchasing a house?
- What is your favorite season of the year?
- Do you think that we should eliminate unemployment insurance so people will be motivated to get a job?
- What do you think causes politicians to be so nasty to one another?
- How many televisions are in your home?
- How much more important is location than price when purchasing a house?
- Do you think that we should eliminate unemployment insurance so people will be motivated to get a job?
- What do you think causes politicians to be so nasty to one another?
For a sample with x¯x¯ =15, s=2, and n=25, which of the following formula would calculate the upper bound of the 95% confidence interval for the true population mean? Please note that the Excel functions for confidence intervals are CONFIDENCE.NORM(alpha, standard_dev, size) and CONFIDENCE.T(alpha, standard_dev, size).
- =15+CONFIDENCE.T(0.05,2,25)
- =15+CONFIDENCE.T(0.025,2,25)
- =15+CONFIDENCE.NORM(0.05,2,25)
- =15+CONFIDENCE.NORM(0.025,2,25)
=15+CONFIDENCE.T(0.05,2,25)
A travel agent wants to determine how much the average client is willing to pay for a weekend at an all-expense paid resort. The agent surveys 30 clients and finds that the average willingness to pay is $2,500 with a standard deviation of $840. However, the travel agent is not satisfied and wants to be 95% confident that the sample mean falls within $150 of the true average. What is the minimum number of clients the travel agent should survey? Note that z=1.96 for a 95% confidence interval.
Please give your answer as an integer with no decimal point and no digits to the right of the decimal point.
[BLANK]
121
A bar owner wants to know if the installation of large-screen TV over the bar has increased the number of drinks sold per hour. Before the TVs were installed, the bar sold an average of 162 drinks per hour. What alternative hypothesis should the manager use to test this claim?
- µ ≠ 162 drinks
- µ ≤ 162 drinks
- µ < 162 drinks
- µ > 162 drinks
µ > 162 drinks
A popular hair salon wants to gather data about how returning customers rate the quality of the service they received during their most recent appointment. The owner decides to use a survey to gather this data. What is the BEST option for selecting respondents to the survey?
- Place paper surveys near the entrance of the hair salon.
- Randomly select a sample of returning customers from appointment records and mail them a survey.
- Ask for volunteers among returning customers and conduct in-person surveys with them during their appointment.
- Conduct a phone survey of all customers who have received blonde highlights in the salon in the last six months.
Randomly select a sample of returning customers from appointment records and mail them a survey.
Assuming that all else remains constant, what happens to a confidence interval around the mean if we raise the sample size from 25 to 100?
- The width of the confidence interval remains the same.
- The width of the confidence interval widens.
- The width of the confidence interval narrows.
- The answer cannot be determined without further information.
The width of the confidence interval narrows.
The manager of a small bar is trying to decide whether to invest in a large-screen television. The manager leases a television for ten weeks and monitors sales during that period. Before the manager installed the television, average weekly revenue was approximately $27,000. With the television installed, average weekly revenue was approximately $32,000. After performing a hypothesis test, the editor obtained a p-value of 0.04. Assuming a 95% confidence level, which of the following conclusions is correct?
- Do not reject the null hypothesis, and conclude that the television does not increase revenue.
- Do not reject the null hypothesis, and conclude that the television increases revenue.
- Reject the alternative hypothesis, and conclude that the television increases revenue
- Reject the null hypothesis, and conclude that the television increases revenue.
Reject the null hypothesis, and conclude that the television increases revenue.
The manager of a factory that is making an average of 14,000 pints of ice cream a day decides to start playing music for employees, believing this decision will increase both employee morale and productivity. However, the manager is concerned about the possibility that the music could distract employees, thereby decreasing productivity. After a month of playing music, the factory was making an average of 13,518 pints a day. The manager runs a two-sided hypothesis test to determine if the number of pints produced has changed. The p-value of the test is 0.238. What does this say about ice cream production?
- If there were no actual change in the average number of pints of ice cream produced daily, the chance of seeing average ice cream production as low as 13,518 pints would be 23.8%.
- There is a 76.2% chance that the mean number of pints of ice cream produced daily has changed since the manager started playing music.
- There is a 76.2% chance that the sample mean number of pints of ice cream produced is 13,518 a day.
- The manager should expect to produce more than 13,518 pints of ice cream on 23.8% of the days that the factory is running.
If there were no actual change in the average number of pints of ice cream produced daily, the chance of seeing average ice cream production as low as 13,518 pints would be 23.8%.
If a standardized test has a mean score of 500 and standard deviation of 100, what percentage of test-takers score between 500 and 600?
- 95%
- 68%
- 34%
- 50%
34%
The linear relationship between two variables can be statistically significant but not explain a large percentage of the variation between the two variables. This would correspond to which pair of R^2 and p-value?
- Low R-squared, Low p-value
- Low R-squared, High p-value
- High R-squared, Low p-value
- High R-squared, High p-value
Low R-squared, Low p-value
A professor wants to know if the average exam score differs between students who attended a review session and those who did not attend. What null hypothesis should the professor use to test this claim?
- µattended > µdid not attend
- µattended ≥ µdid not attend
- µattended ≤ µdid not attend
- µattended = µdid not attend
µattended = µdid not attend



