Linked Questions

38 votes
4 answers
3k views

Are inconsistent estimators ever preferable?

Consistency is obviously a natural and important property of estimators, but are there situations where it may be better to use an inconsistent estimator rather than a consistent one? More ...
MånsT's user avatar
  • 12k
12 votes
3 answers
2k views

T-consistency vs. P-consistency

Francis Diebold has a blog post "Causality and T-Consistency vs. Correlation and P-Consistency" where he presents the notion of P-consistency, or presistency: Consider a standard linear regression ...
Richard Hardy's user avatar
11 votes
2 answers
32k views

Understanding and interpreting consistency of OLS

Many econometrics textbooks (e.g. Wooldridge, "Econometric analysis...") simply write something similar to: "If the population model is $y = xB + u$ and (1) $\text{Cov}(X,U) = 0$; (2) $X'X$ is full ...
Michal's user avatar
  • 113
20 votes
2 answers
809 views

Minimizing bias in explanatory modeling, why? (Galit Shmueli's "To Explain or to Predict")

This question references Galit Shmueli's paper "To Explain or to Predict". Specifically, in section 1.5, "Explaining and Prediction are Different", Professor Shmueli writes: In explanatory ...
Matthew Drury's user avatar
9 votes
2 answers
2k views

What is the relationship between minimizing prediction error versus parameter estimation error?

With the advent of statistical learning techniques, people are talking a lot about prediction error, while in classical statistics, one is focusing on parameter estimation error. What is the ...
Matifou's user avatar
  • 3,114
2 votes
3 answers
2k 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 ...
sabiste's user avatar
  • 31
0 votes
1 answer
3k views

OLS Assumption-No correlation should be there between error term and independent variable and error term and dependent variable

My question is that does endogeneity exists if there is correlation between dependent variable and error term, but not in between error term and independent variable. So for Ex, we know there should ...
divyam sureka's user avatar
3 votes
2 answers
1k 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 ...
user35734's user avatar
  • 406
3 votes
1 answer
505 views

endogenous regressor and correlation

In a widely cited paper by Antonakis et al. (2010), they mention: If the relation between x and y is due, in part, to other reasons, then x is endogenous, and the coefficient of x cannot be ...
user6441253's user avatar
10 votes
1 answer
593 views

About the meaning of ARMA parameters

I suppose that the main scope of an econometric models should be predictive or causal inference. Following this perspective it was shown that underspecified model can perform better than the correct ...
markowitz's user avatar
  • 5,729
3 votes
2 answers
406 views

Models with low variance but high bias

If we have a classification/regression problem, when would we generally prefer to use families of models with high bias and low variance like multiple regression (logistic regression for ...
Math_cat's user avatar
3 votes
0 answers
1k views

Regression: Causation vs Prediction vs Description

In my experience it seems me that the interpretation about regression, its meaning and its scope, are debatable and great confusion exist about those things. It seems me that confusions are not go ...
markowitz's user avatar
  • 5,729
2 votes
1 answer
356 views

Clarification on the assumptions $E[u|x]=0$ and the $x_i$ being fixed in repeated samples in Wooldridge Introductory Econometrics

The author is writing on the assumption $E[u|x]=0$. The part of the text which is not clear to me is this (the red lines emphasize where the critical portions are located) : In the first piece I don'...
Tortar's user avatar
  • 356
2 votes
3 answers
517 views

In regression analysis, data generate model or model generate data?

I am learning regression analysis and in starting of that I have encountered two statements: S1: model generates data S2: data generates model Given that one is correct, so I picked up S2, thinking ...
Singh's user avatar
  • 221
2 votes
0 answers
594 views

Machine Learning with few observations

Is common to say that Machine Learning techniques represent are purely data driven methods, and them are effective only if we have a large amount of data. I focused here on supervised/predictive ...
markowitz's user avatar
  • 5,729

15 30 50 per page