Browsing by Author "Bergtold, Jason Scott"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Advances in Applied Econometrics: Binary Discrete Choice Models, Artificial Neural Networks, and Asymmetries in the FAST Multistage Demand System
    Bergtold, Jason Scott (Virginia Tech, 2004-04-14)
    The dissertation examines advancements in the methods and techniques used in the field of econometrics. These advancements include: (i) a re-examination of the underlying statistical foundations of statistical models with binary dependent variables. (ii) using feed-forward backpropagation artificial neural networks for modeling dichotomous choice processes, and (iii) the estimation of unconditional demand elasticities using the flexible multistage demand system with asymmetric partitions and fixed effects across time. The first paper re-examines the underlying statistical foundations of statistical models with binary dependent variables using the probabilistic reduction approach. This re-examination leads to the development of the Bernoulli Regression Model, a family of statistical models arising from conditional Bernoulli distributions. The paper provides guidelines for specifying and estimating a Bernoulli Regression Model, as well as, methods for generating and simulating conditional binary choice processes. Finally, the Multinomial Regression Model is presented as a direct extension. The second paper empirically compares the out-of-sample predictive capabilities of artificial neural networks to binary logit and probit models. To facilitate this comparison, the statistical foundations of dichotomous choice models and feed-forward backpropagation artificial neural networks (FFBANNs) are re-evaluated. Using contingent valuation survey data, the paper shows that FFBANNs provide an alternative to the binary logit and probit models with linear index functions. Direct comparisons between the models showed that the FFBANNs performed marginally better than the logit and probit models for a number of within-sample and out-of-sample performance measures, but in the majority of cases these differences were not statistically significant. In addition, guidelines for modeling contingent valuation survey data and techniques for estimating median WTP measures using FFBANNs are examined. The third paper estimates a set of unconditional price and expenditure elasticities for 49 different processed food categories using scanner data and the flexible and symmetric translog (FAST) multistage demand system. Due to the use of panel data and the presence of heterogeneity across time, temporal fixed effects were incorporated into the model. Overall, estimated price elasticities are larger, in absolute terms, than previous estimates. The use of disaggregated product groupings, scanner data, and the estimation of unconditional elasticities likely accounts for these differences.
  • Thumbnail Image
    Projected Economic Impacts of the New Partnership Agreement Between the EU and ACP States on the Senegalese Groundnut Sector
    Bergtold, Jason Scott (Virginia Tech, 2001-08-31)
    With the signing of the New Partnership Agreement (Cotonou Convention) between the European Union and the African, Caribbean, and Pacific States in June 2000, the trading relationship between Senegal and the European Union (EU) has taken a new direction. Under the new agreement, Senegal must decide by 2004 if it will enter into a Regional Economic Partnership Agreement (REPA) with the EU, similar to a free trade arrangement, or move to an enhanced form of the Generalized System of Preferences (GSP). Given the high percentage of Senegalese groundnut products that are exported to the European Union and the significance of the groundnut sector to the Senegalese economy, this study examines the economic impacts of both options on the Senegalese groundnut sector in conjunction with changes in development funding, infrastructural investments, and structural adjustment policies. Overall, the study finds that the REPA option is the more beneficial for the Senegalese groundnut sector. This result stems partially from the ability of increases in development funding to offset any adverse economic impacts caused by the REPA. Though overall more harmful than a REPA, moving to an enhanced GSP does have the benefit of increasing groundnut (in-shell and shelled) exports by a significant amount. Thus, the Senegalese government must weigh the benefit of a boost in the confectionery sector against the adverse impact on producers caused by the GSP. This study provides needed information for policy decisions by the Senegalese government, and a framework for future modeling efforts pertaining to the Senegalese groundnut sector.