Showing 1 - 10 of 222
The problem of variable selection for linear regression in a high dimension model is considered. A new method, called Extended-VISA (Ext-VISA), is proposed to simultaneously select variables and encourage a grouping effect where strongly correlated predictors tend to be in or out of the model...
Persistent link: https://www.econbiz.de/10011056435
A Monte Carlo algorithm is said to be adaptive if it can adjust automatically its current proposal distribution, using past simulations. The choice of the parametric family that defines the set of proposal distributions is critical for a good performance. We treat the problem of constructing...
Persistent link: https://www.econbiz.de/10011073707
A Monte Carlo algorithm is said to be adaptive if it automatically calibrates its current proposal distribution using past simulations. The choice of the parametric family that defines the set of proposal distributions is critical for a good performance. In this paper, we present such a...
Persistent link: https://www.econbiz.de/10011074311
Marketing researchers are increasingly taking advantage of the instrumental variable (IV)-free Gaussian copula approach. They use this method to identify and correct endogeneity when estimating regression models with non-experimental data. The Gaussian copula approach's original presentation and...
Persistent link: https://www.econbiz.de/10014501601
Enhanced machine learning methods provide an encouraging alternative to forecast asset prices by extending or generalizing the possible model specifications compared to conventional linear regression methods. Even if enhanced methods of machine learning in the literature often lead to better...
Persistent link: https://www.econbiz.de/10014503903
Motivated by an example in nutritional epidemiology, we investigate some design and analysis aspects of linear measurement error models with missing surrogate data. The specific problem investigated consists of an initial large sample in which the response (a food frequency questionnaire, FFQ)...
Persistent link: https://www.econbiz.de/10010310753
Data from the automatic monitoring of intensive care patients exhibits trends, outliers, and level changes as well as periods of relative constancy. All this is overlaid with a high level of noise and there are dependencies between the different items measured. Current monitoring systems tend to...
Persistent link: https://www.econbiz.de/10010316710
Considerable attention has been recently paid to the use of surrogate endpoints in clinical research. We deal with the situation where the two endpoints are both right censored. While proportional hazards analyses are typically used for this setting, their use leads to several complications. In...
Persistent link: https://www.econbiz.de/10009477556
When doing two-way fixed effects OLS estimations, both the variances and covariance of the fixed effects are biased. A formula for a bias correction is known, but in large datasets it involves inverses of impractically large matrices. We detail how to compute the bias correction in this case.
Persistent link: https://www.econbiz.de/10011335587
This survey has the purpose to prove as and how much the volume of exported sugar by Santos port interferes in the freight value negotiated for fertilizer distribution for the final customer, in São Paulo State. For people who are directly connected to fertilizer logistic, it is very important...
Persistent link: https://www.econbiz.de/10009446478