Question 1
In Regression, “Marginal” slope and “Partial” slope coincide if the explanatory variables are dependent.
TRUE
FALSE
The IIT Madras BS Business Analytics (Business Analytics) End Term paper sat on 30 Apr 2023, in the January 2023 term, set QPD1-S2: 31 questions for 45 marks in 180 minutes. Every question is below with its answer. Take it as a timed mock test to be marked, or read it through first.
In Regression, “Marginal” slope and “Partial” slope coincide if the explanatory variables are dependent.
TRUE
FALSE
Correct answer
FALSE
The data on emissions from vehicular traffic for the first six months in 2023 and 2022 are provided in the Table below. If an analyst wants to develop a visualization that highlights “The months with the highest increase in emissions in 2023 as compared to 2022”, then which of the formulas would be apt to capture the required information for presentation
| Month | Tons of CO2 Emissions in 2022 | Tons of CO2 Emissions in 2023 |
|---|---|---|
| Jan | 1.2 | 1.5 |
| Feb | 1.1 | 1.4 |
| Mar | 1.5 | 1.8 |
| April | 1.8 | 2.2 |
| May | 2.4 | 2.5 |
| June | 2.7 | 2.9 |
(Tons of CO2 Emissions in 2023 - Tons of CO2 Emissions in 2022)/ Tons of CO2 Emissions in 2022
(Tons of CO2 Emissions in 2023 - Tons of CO2 Emissions in 2022)
None of these
Correct answer
(Tons of CO2 Emissions in 2023 - Tons of CO2 Emissions in 2022)
You are solving a regression problem with 8 explanatory variables. The data has 150 observations, and the R-square value was found to be 0.75. You are adding one more explanatory variable to the dataset, making a total of 9 variables. The adjusted R square value increases to 0.86. What does it signify?
The new variable does not improve the model
The new variable alone has high explanatory power
Adjusted R squared can never be greater than R squared. Calculation error
None of these
Correct answer
Adjusted R squared can never be greater than R squared. Calculation error
How is Hypothetical Composite Unit computed in DEA for a DMU using graphical method?
By drawing line connecting the origin and DMU
By moving horizontally towards the frontier
By moving vertically towards the frontier
All of these
Correct answer
By drawing line connecting the origin and DMU
How to identify the HCU of an inefficient DMU using Linear Programming Method?
Using the shadow price
By moving horizontally towards the frontier
By moving vertically towards the frontier
All of these
Correct answer
Using the shadow price
The following is the Primal LP Formulation for a resource allocation problem. Given this, answer the subquestions
Objective: Maximize
Constraint-1:
Constraint-2:
Constraint-3:
Constraint-4:
Constraint-5:
Constraint-6: , , , , , are all non-negative
How many constraints will be present in the dual formulation?
Correct answer: 6
The following is the Primal LP Formulation for a resource allocation problem. Given this, answer the subquestions
Objective: Maximize
Constraint-1:
Constraint-2:
Constraint-3:
Constraint-4:
Constraint-5:
Constraint-6: , , , , , are all non-negative
How many decision variables will be required to formulate the dual?
Correct answer: 5
The following is the Primal LP Formulation for a resource allocation problem. Given this, answer the subquestions
Objective: Maximize
Constraint-1:
Constraint-2:
Constraint-3:
Constraint-4:
Constraint-5:
Constraint-6: , , , , , are all non-negative
What is the objective function “co-efficient” for the dual decision variable corresponding to the “Constraint-4” in the primal?
Correct answer: 20
The following is the Primal LP Formulation for a resource allocation problem. Given this, answer the subquestions
Objective: Maximize
Constraint-1:
Constraint-2:
Constraint-3:
Constraint-4:
Constraint-5:
Constraint-6: , , , , , are all non-negative
Which of the following is/ are valid constraints/ objective function in the dual formulation for the provided primal formulation
{Note: Xi – represents the i^(th) decision variable in the dual formulation}
Minimize (10X1 + 20X2 + 5X3 + 7X4 +12X5 + 11X6)
Minimize (200X1 + 50X2 + 70X3 + 20X4 +70X5 + 70X6)
X1+ 2X2 + 4X3 + X4>= 10
X1+ X2 + 4X3 + X4 <= 10
X1 >= 12
X1 <= 12
X1 + 3X2 + X4 >= 5
X1 + 3X2 + X4 <= 5
Correct answers
X1 >= 12
X1 + 3X2 + X4 >= 5
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
Considering a threshold of 0.7, how many “True Positives” are present in the confusion matrix if the aim is to predict if a student will pass the course?
NOTE: Enter the answer as a numeric percentage value rounded to the nearest integer without the % symbol.
Correct answer: 3
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
Considering a threshold of 0.7, how many “False Positives” are present in the confusion matrix if the aim is to predict if a student will pass the course?
NOTE: Enter the answer as a numeric percentage value rounded to the nearest integer without the % symbol.
Correct answer: 1
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
Considering a threshold of 0.7, how many “False Negatives” are present in the confusion matrix if the aim is to predict if a student will pass the course?
NOTE: Enter the answer as a numeric percentage value rounded to the nearest integer without the % symbol.
Correct answer: 0
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
Considering a threshold of 0.7, how many “True Negatives” are present in the confusion matrix if the aim is to predict if a student will pass the course?
NOTE: Enter the answer as a numeric percentage value rounded to the nearest integer without the % symbol.
Correct answer: 2
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
What is the accuracy of the built logistic model for predicting if a student will fail the course if a threshold of 0.7 is taken?
NOTE: Enter the answer as a numeric percentage value rounded to two decimal places without the % symbol. For example, if your answer is “10.256 %”, enter it as “10.26”
Correct answer: 83.5 (accepted within ±0.5)
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
What is the precision of the built logistic model for predicting if a student will pass the course if a threshold of 0.7 is taken?
NOTE: Enter the answer as a numeric percentage value rounded to the nearest integer without the % symbol.
Correct answer: 75
A logistic regression model is fit to predict if a student will pass the BA course (Y=1 pass, Y=0 fail). The results of the fitted model are given in the table below. Then answer the given subquestions.
What is the recall of the built logistic model for predicting if a student will fail the course if a threshold of 0.7 is taken?
NOTE: Enter the answer as a numeric percentage value rounded to two decimal places without the % symbol. For example, if your answer is “10.256 %”, enter it as “10.26”
Correct answer: 66.5 (accepted within ±0.5)
You are given the sales volume of three brands, “A”, “B”, and “C” in 4 cities in the table below. Using this information, answer the given subquestions.
What is the expected frequency of “Chennai” people preferring “Brand-B”?
NOTE: If your answer is in decimal, enter it rounded to two decimal places. For example, if your answer is “10.256”, enter it as “10.26”
Correct answer: 155 (accepted within ±2)
You are given the sales volume of three brands, “A”, “B”, and “C” in 4 cities in the table below. Using this information, answer the given subquestions.
What is the expected frequency for “Delhi” people preferring “Brand-C”?
NOTE: If your answer is in decimal, enter it rounded to two decimal places. For example, if your answer is “10.256”, enter it as “10.26”
Correct answer: 120 (accepted within ±2)
You are given the sales volume of three brands, “A”, “B”, and “C” in 4 cities in the table below. Using this information, answer the given subquestions.
What is the value of the computed Chi-Square test statistic?
NOTE: If your answer is in decimal, enter it rounded to two decimal places. For example, if your answer is “10.256”, enter it as “10.26”
Correct answer: 128 (accepted within ±3)
You are given the sales volume of three brands, “A”, “B”, and “C” in 4 cities in the table below. Using this information, answer the given subquestions.
What is the degrees of freedom for the chi-square test that you perform for this problem? NOTE: Enter your answer to the nearest integer.
Correct answer: 6
You are given the sales volume of three brands, “A”, “B”, and “C” in 4 cities in the table below. Using this information, answer the given subquestions.
At the significance level 0.01, chi-squared tabular value is 16.18. What do you conclude?
Reject the null hypothesis and conclude that the categorical variables are not independent
Accept the null hypothesis and conclude that the categorical variables are not independent
Accept the null hypothesis and conclude that the categorical variables are independent
Reject the null hypothesis and conclude that the categorical variables are independent
Accept the alternative hypothesis and conclude that the categorical variables are independent
Fail to accept the alternative hypothesis and conclude that the categorical variables are not independent
Fail to reject the alternative hypothesis and conclude that the categorical variables are independent
None of these
Correct answer
Reject the null hypothesis and conclude that the categorical variables are not independent
When do you choose “charts” for representing data?
To show how data changes over time
Show distribution of data
Show complete data
Show slice of data
Correct answers
To show how data changes over time
Show distribution of data
Show slice of data
When performing the goodness of fit test by grouping the given observations into bins, the expected frequency represents the __ (choose all that are applicable)
Probability Mass Function
Probability Density Function
Cumulative Distribution Function
The actual count of values in the sample that fall in each bin
None of these
Correct answers
Probability Mass Function
Probability Density Function
If a constant elasticity curve models the demand response curve for the data given in the following table, then answer the given subquestions
What is the demand when the price is Rs.1?
Correct answer: 10
If a constant elasticity curve models the demand response curve for the data given in the following table, then answer the given subquestions
What is the price elasticity for the demand response curve?
Correct answer: 1
The relationship between Demand “D” and Selling Price “P” is given by the equation D(p) = 120 – 5*P. If the intention is to maximize the profit, then what is the optimal selling price if the item is going to be sold at Rs. 20 per unit?
Correct answer: 22
There are 6 business units. There are two outputs and one input under consideration. You are solving the optimization problem for business unit 4 and find that the efficiency is 0.8. You find that the dual variables corresponding to the constraints of business units 3 and 5 are non-zero and the dual variables corresponding to the constraints of other units are zero. The dual variables corresponding to the constraints of business units 3 and 5 are 0.3 and 0.5 respectively. You are given the following table where sales and number of leads are the two outputs. What is the sales in HCU 4?
Correct answer: 9500 (accepted within ±1)
The table below provides the summary statistic for a random variable. Then what distribution could be a good fit for this random variable? (select all that is/are applicable)
Poisson distribution
Symmetric Gaussian distribution
Uniform distribution
Exponential distribution
Correct answer
Poisson distribution
What is productive efficiency?
It is an aspect of economic efficiency focussing on maximizing the output under given constraints.
Productive efficiency does not worry about optimal allocation, or choice of products
Effective usage of technology for maximizing the revenue
Consists of all combinations of outputs such that the production of one product cannot be increased without sacrificing the output of the other (without any change in technology)
Both It is an aspect of economic efficiency focussing on maximizing the output under given constraints & Productive efficiency does not worry about optimal allocation, or choice of products
Correct answer
Both It is an aspect of economic efficiency focussing on maximizing the output under given constraints & Productive efficiency does not worry about optimal allocation, or choice of products
Normalizing constraint for the denominator
All DMUs including k will have weights assigned by k and it will be less than 1
Non-negativity constraint for the decision variables
All of these
Correct answer
All of these
There are 7 business units and you are using the DEA to compare them. You solve the LP for business unit 4. You find from the constraint expression that business unit 2 has obtained an efficiency of 1 and business unit 7 has obtained an efficiency of 1 with the optimal weights of business unit 5. Which of the following statements is correct?
Business unit 3 may be inefficient
Business unit 2 will be efficient
Business unit 7 may be inefficient
Business unit 7 will be efficient
Correct answers
Business unit 2 will be efficient
Business unit 7 will be efficient