When teaching cost behavior in a managerial or cost accounting course, we explain that there are various methods a company can use to estimate its fixed and variable costs, including regression ...

Conditional heteroscedasticity has often been used in modelling and understanding the variability of statistical data. Under a general set-up which includes nonlinear time series models as a special ...

We propose the structure of heteroscedastic variances by using some specified variance functions and some covariates with unknown parameters. Under this setting, we construct moment-type estimators of ...