How to compare interpretatively different models for the conditional variance function

This study considers regression-type models with heteroscedastic Gaussian errors. The conditional variance is assumed to depend on the explanatory variables via a parametric or non-parametric variance function. The variance function has usually been selected on the basis of the log-likelihoods of fitted models. However, log-likelihood is a difficult quantity to interpret – the practical importance of differences in log-likelihoods has been difficult to assess. This study overcomes these difficulties by transforming the difference in log-likelihood to easily interpretative difference in the error of predicted deviation. In addition, methods for testing the statistical significance of the observed difference in test data log-likelihood are proposed.

[1]  Norman R. Swanson,et al.  A Test for Comparing Multiple Misspecified Conditional Distributions , 2003 .

[2]  Anthony S. Tay,et al.  Evaluating Density Forecasts with Applications to Financial Risk Management , 1998 .

[3]  Ananda Sen,et al.  The Theory of Dispersion Models , 1997, Technometrics.

[4]  G. Giordano Evaluating , 1995 .

[5]  J. Röning,et al.  Planning of Strength Margins Using Joint Modeling of Mean and Dispersion , 2006 .

[6]  Norman R. Swanson,et al.  Predictive Density and Conditional Confidence Interval Accuracy Tests , 2004 .

[7]  Ðani Juricic,et al.  Estimation of the confidence limits for the quadratic forms in normal variables using a simple Gaussian distribution approximation , 2005, Comput. Stat..

[8]  Milton Abramowitz,et al.  Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables , 1964 .

[9]  A. Raftery,et al.  Probabilistic forecasts, calibration and sharpness , 2007 .

[10]  Gianni Amisano,et al.  Evaluating the Predictive Distributions of Bayesian Models of Asset Returns , 2008 .

[11]  Chris Kirby,et al.  The Economic Value of Volatility Timing , 2000 .

[12]  P. A. P. Moran,et al.  An introduction to probability theory , 1968 .

[13]  I-Cheng Yeh,et al.  Modeling of strength of high-performance concrete using artificial neural networks , 1998 .

[14]  M. Aitkin Modelling variance heterogeneity in normal regression using GLIM , 1987 .

[15]  Gavin C. Cawley,et al.  Heteroscedastic kernel ridge regression , 2004, Neurocomputing.

[16]  R. Rigby,et al.  Construction of Reference Centiles Using Mean and Dispersion Additive Models , 2000 .

[17]  Norman R. Swanson,et al.  A TEST FOR COMPARING MULTIPLE MISSPECIFIED CONDITIONAL INTERVAL MODELS , 2005, Econometric Theory.

[18]  Yong Bao,et al.  Comparing Density Forecast Models , 2007 .

[19]  A. Raftery,et al.  Strictly Proper Scoring Rules, Prediction, and Estimation , 2007 .

[20]  M. C. Jones,et al.  Likelihood-Based Local Linear Estimation of the Conditional Variance Function , 2004 .

[21]  James Mitchell,et al.  Evaluating, Comparing and Combining Density Forecasts Using the Klic with an Application to the Bank of England and Niesr 'Fan' Charts of Inflation , 2005 .

[22]  Halbert White,et al.  Tests of Conditional Predictive Ability , 2003 .

[23]  Elvezio Ronchetti,et al.  Robust Linear Model Selection by Cross-Validation , 1997 .

[24]  Gordon K. Smyth,et al.  Exact and approximate REML for heteroscedastic regression , 2001 .

[25]  Gianni Amisano,et al.  Comparing Density Forecasts via Weighted Likelihood Ratio Tests , 2007 .

[26]  Gavin C. Cawley,et al.  A simple trick for constructing Bayesian formulations of sparse kernel learning methods , 2005, Proceedings. 2005 IEEE International Joint Conference on Neural Networks, 2005..

[27]  Feller William,et al.  An Introduction To Probability Theory And Its Applications , 1950 .

[28]  Gavin C. Cawley,et al.  Maximum likelihood cost functions for neural network models of air quality data , 2003 .