Showing 1 - 10 of 191
the tests for forecast optimality under unknown loss function as developed in Patton and Timmermann (2007). We apply one … yields better forecasts in terms of fit. In terms of optimality the effect of adjustments for the forecasts are limited …
Persistent link: https://www.econbiz.de/10010837998
Over the recent years, Fireworks Algorithm has recorded an increasing success on solving continuous optimization problems, due to its efficiency, simplicity and more importantly its rapid convergence to good optimums. Thus, the Fireworks Algorithm performance is now widely comparable with the...
Persistent link: https://www.econbiz.de/10012042932
We develop uniformly valid confidence regions for regression coefficients in a high-dimensional sparse least absolute deviation/median regression model. The setting is one where the number of regressors p could be large in comparison to the sample size n, but only s << n of them are needed to accurately describe the regression function. Our new methods are based on the instrumental median regression estimator that assembles the optimal estimating equation from the output of the post l1-penalized median regression and post l1-penalized least squares in an auxiliary equation. The estimating equation is immunized against non-regular estimation of nuisance part of the median regression function, in the sense of Neyman. We establish that in a homoscedastic regression model, the instrumental median regression estimator of a single regression coefficient is asymptotically root-n normal uniformly with respect to the underlying sparse model. The resulting confidence regions are valid uniformly with respect to the underlying model. We illustrate the value of uniformity with Monte-Carlo experiments which demonstrate that standard/naive post-selection inference breaks down over large parts of the parameter space, and the proposed method does not. We then generalize our method to the case where p1 > n regression coefficients...</<>
Persistent link: https://www.econbiz.de/10010368203
This paper considers inference in logistic regression models with high dimensional data. We propose new methods for estimating and constructing confidence regions for a regression parameter of primary interest »0, a parameter in front of the regressor of interest, such as the treatment variable...
Persistent link: https://www.econbiz.de/10010368235
Here we present an expository, general analysis of valid post-selection or post-regularization inference about a low-dimensional target parameter in the presence of a very high-dimensional nuisance parameter which is estimated using selection or regularization methods. Our analysis provides a...
Persistent link: https://www.econbiz.de/10011594345
Most modern supervised statistical/machine learning (ML) methods are explicitly designed to solve prediction problems very well. Achieving this goal does not imply that these methods automatically deliver good estimators of causal parameters. Examples of such parameters include individual...
Persistent link: https://www.econbiz.de/10011594359
Discretionary monetary policy produces a dynamic loss in the New Keynesian model in the presence of cost-push shocks. The possibility to commit to a specific policy rule can increase welfare. A number of authors since Woodford (1999) have argued in favour of a timeless perspective rule as an...
Persistent link: https://www.econbiz.de/10011604763
The paper proves the existence and uniqueness of a noncooperative steady state in the context of a model of climate change. It also explores the possibility of cooperation and attainment of an optimal steady state. It is shown that the problem is similar to that in the static model (Chander and...
Persistent link: https://www.econbiz.de/10011608804
The aim of this paper is to assess the capacity of labour mobility in the euro area to act as an adjustment mechanism in the event of an asymmetric shock. According to the optimum currency area theory, labour mobility has been emphasized as one of the main adjustment mechanism. Given the present...
Persistent link: https://www.econbiz.de/10012016978
We study optimality properties in finite samples for time-varying volatility models driven by the score of the … predictive likelihood function. Available optimality results for this class of models suffer from two drawbacks. First, they are … only asymptotically valid when evaluated at the pseudo-true parameter. Second, they only provide an optimality result `on …
Persistent link: https://www.econbiz.de/10011819504