Linked Questions

32
votes
6answers
3k views

Under which assumptions a regression can be interpreted causally?

First, don't panic. Yes, there are many similar question on this site. But I believe none gives a conclusive answer to the question below. Please bear with me. Consider a data generation process $\...
15
votes
2answers
398 views

How would econometricians answer the objections and recommendations raised by Chen and Pearl (2013)?

In their article, Chen and Pearl (2013), critically examined 6 econometric textbooks, among these the textbooks written by Wooldridge (2009) {the introductory book}, and Stock & Watson (2011). ...
2
votes
2answers
836 views

What is the actual definition of endogeneity?

I've been learning about endogeneity but after looking around online I've gotten more and more confused about what the definition is. Most pages say that in a model $y=X\beta+\epsilon$ the definition ...
6
votes
1answer
304 views

What's the DGP in causal inference?

This question come from this discussion (Under which assumptions a regression can be interpreted causally? ). That discussion touch too arguments and is not possible to speak about all things there. ...
2
votes
2answers
868 views

Multiple Linear Regression Zero Conditional Mean Assumption

Greene [1] and Wooldridge [2] emphasize that in the standard multiple linear regression model $${\bf y}=X{\bf b}+{\bf e}$$ a key assumption is that $$E[{\bf e}|X]=E[{\bf e}].$$ Or, in other words, $X$...
1
vote
2answers
403 views

Regression's population parameters

Suppose I've specified a linear regression model: $$ Y = \beta_0 + \beta_1 X + \epsilon $$ where $\beta_0$, $\beta_1$ are the population parameters. My question is: why are these parameters ...
1
vote
1answer
612 views

Does homoscedasticity imply that the regressor variables and the errors are uncorrelated?

By OLS regression equation: $$Y = a + bX + e$$ My thoughts are that homoscedasticity by definition imply that $Var(Y|X) = Var(e|X)=$ constant, then this would imply that $Var(e|X) = Var(e)$ which ...
1
vote
3answers
394 views

Endogeneity testing using correlation test

I am currently testing my linear model using OLS method. The last thing I have to test is endogeneity issue. Is it enough if I test each explanatory variable for correletion with error term? Than ...
0
votes
1answer
131 views

Random Sampling: Weak and Strong Exogenity

$Y \ = \ X' \beta \ + \ e $ Where $Y = (y_1, ..., y_n)$ and $\beta = (\beta_0,..., \beta_k)$. Why would Weak Exogenity under random sampling produce Strong Exogenity? I know that weak exogenity is ...
4
votes
2answers
79 views

Structural models and relationship (statistical associations)

I'm starting to study econometrics from the Wooldrige's book. But some doubts arise regarding the structural model, its definition and its comprehension in general. Let's look at the author's opinion. ...