HBX final Questions And Answers Verified By
Experts
Suppose we want to assign dummy variables to the seasons (Winter, Spring, Summer, Fall). How
many dummy variables do we need? 3
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.) It's all the variables that make up the price during the year...
The variables for location and wine consumption are collinear. VS:
The variable for location is a better predictor than wine consumption. The first is true of
this manager's shitty regression analysis experiments because that's what happens when the
coefficient for one variable is no longer significant and the other variable's R-squared value goes
up, yet the adjusted R-squared has decreased.
average vs averageIF
(Don't forget descriptive statistics)
~mean AverageIF is a conditional, limiting scope to something. Like if we're looking for
the average IF so and so is doing something...
square root of variance = standard dev.
, HBX final Questions And Answers Verified By
Experts
scatterplot showing a downward 'slope' (really dots descending); some more clumped on each
end, few in middle. What's the likely correlation?
-.8, -.2, .2, or .8? -.8
watch for ':' vs ','
If the prices are listed in cells A2:A26, which of the following Excel functions would calculate
the 95th percentile? PERCENTILE.INC(A2:A26,0.95)
NOT "0.05"!!!
For a sample with 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?
=15+CONFIDENCE.T(0.05,2,25)
NOT
=15+CONFIDENCE.T(0.025,2,25)
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
, HBX final Questions And Answers Verified By
Experts
gather this data. What is the BEST option for selecting respondents to the survey?
Randomly select a sample of returning customers from appointment records and mail
them a survey.
NOT:
Phone interview,s in person surveys during appointments... or paper surveys near the entrance.
duh tothe last two
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?
Does the width and confidence level narrow or widen? Narrows!
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%.
NOT
Experts
Suppose we want to assign dummy variables to the seasons (Winter, Spring, Summer, Fall). How
many dummy variables do we need? 3
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.) It's all the variables that make up the price during the year...
The variables for location and wine consumption are collinear. VS:
The variable for location is a better predictor than wine consumption. The first is true of
this manager's shitty regression analysis experiments because that's what happens when the
coefficient for one variable is no longer significant and the other variable's R-squared value goes
up, yet the adjusted R-squared has decreased.
average vs averageIF
(Don't forget descriptive statistics)
~mean AverageIF is a conditional, limiting scope to something. Like if we're looking for
the average IF so and so is doing something...
square root of variance = standard dev.
, HBX final Questions And Answers Verified By
Experts
scatterplot showing a downward 'slope' (really dots descending); some more clumped on each
end, few in middle. What's the likely correlation?
-.8, -.2, .2, or .8? -.8
watch for ':' vs ','
If the prices are listed in cells A2:A26, which of the following Excel functions would calculate
the 95th percentile? PERCENTILE.INC(A2:A26,0.95)
NOT "0.05"!!!
For a sample with 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?
=15+CONFIDENCE.T(0.05,2,25)
NOT
=15+CONFIDENCE.T(0.025,2,25)
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
, HBX final Questions And Answers Verified By
Experts
gather this data. What is the BEST option for selecting respondents to the survey?
Randomly select a sample of returning customers from appointment records and mail
them a survey.
NOT:
Phone interview,s in person surveys during appointments... or paper surveys near the entrance.
duh tothe last two
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?
Does the width and confidence level narrow or widen? Narrows!
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%.
NOT
