Dummy variables and functional forms: previous year questions
Asked 20 times in 6 exams across 13 years. Newest first.
Practise Dummy variables and functional forms, easy to hard →
Dummy variables and the dummy variable trap
Using 0-1 variables for categories, how to read their coefficients, and the trap of too many.
- IIT JAM 2026 Q13For a sample of employees participating in an annual appraisal, the effect of the participants' performance on their wages is studied. Variables are…
- UGC-NET 2024 Q29ANCOVA models include regressors that are:
- UGC-NET 2024 Q79If a variable has 'm' categories, we can run the regression using:
- JNU 2021 Q67If a quantitative variable has ‘m’ categories, we can introduce
- DSE 2019 Q32Scenario 3: Data from a random sample of 107 home sales in 2003 yielded the regression P̂=119.2+0.485 BD+23.4 BA+0.156 HS+0.002 PS+0.090 A-35.6 PC…
- DSE 2018 Q27Suppose we have estimated y = 10 + 1.5x + 4D, where y is earnings, x is experience, and D = 0 for females, 1 for males. If we had coded the dummy as…
- UoH 2017 Q67As per the rules of the dummy variables, if a quantitative variable has M categories, we can introduce
- DSE 2015 Q41A regression of wages on gender on 200 individuals (150 men) yields Wᵢ=300-50Dᵢ+uᵢ (Dᵢ=1 if male). The average wage in the sample is
- DSE 2014 Q47Consider the linear regression yᵢ=β₁ D1ᵢ+β₂ D2ᵢ+εᵢ, where D1ᵢ=1 for one group of observations and 0 for the other, and D2=1-D1. Can this model be…
- DSE 2011 Q38A researcher wants to test whether there are gender differences in the rates of immunization for boys and girls, after controlling for parental…
Interaction terms and piecewise regressions
Letting slopes differ across groups or ranges.
- DSE 2018 Q39Suppose you have run the regression y = α + β x + γ Urban + θ Immigrant + δ Urban×Immigrant + ϵ, where Urban indicates living in a city and…
- DSE 2016 Q6Consider the following estimated regression relating expenditures on Food (Yᵢ) to Income (Xᵢ): Ŷᵢ=145+0.3Xᵢ-0.1(Xᵢ-Xᵢ*)Dᵢ, where i denotes the…
Log, quadratic and other functional forms
Choosing and interpreting log-log, semi-log, quadratic and reciprocal specifications.
- GATE 2026 Q52The estimated energy demand is given in the Equation below, where, ŷₜ is the estimated value of the log of energy demand at time t. The numbers in…
- GATE 2026 Q64Consider the estimated regression Equation below, where, ŷₜ is the estimated value of the log (to the base e) of real GDP at time t. The numbers in…
- IIT JAM 2026 Q12Let Yₜ be the value of Y in year t. The natural logarithmic value of Yₜ is regressed on t. A simple linear regression yields the statistically…
- GATE 2024 Q51The following table provides different statistical model specifications along with the elasticity of yₜ with respect to xₜ. Which one of the…
- UGC-NET 2023 Q9In the model ln Y_i = a + B X_i + u_i, where ln is the natural log, the elasticity of Y with respect to X is given by:
- DSE 2013 Q48Using ordinary least squares, a market analyst estimates the demand function log X=α+βlog P+ε, where X is output and P is price. In another…
- DSE 2012 Q38Suppose you have 500 observations and you regress wage (measured in rupees per hour) on experience in the labour market, exper (measures in years)…
- DSE 2011 Q8Suppose you have the following estimated regression equation: ln Y=1.2+0.5X. Which of the following is a good interpretation of the estimated…