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on Discrete Choice Models |
| By: | Valeri, Eva; Danielis, Romeo; Pofuk, Tin; Rotaris, Lucia; Rusich, Andrea |
| Abstract: | Il lavoro presenta i risultati di una ricerca di mercato, condotta intervistando 121 persone, residenti in varie regioni italiane e non, avente l’obiettivo di stimare i possibili scenari di penetrazione di automobili con differente tipo di alimentazione in relazione ad eventuali politiche di incentivazione statale, a possibili variazioni nei prezzi dei combustili e nel prezzo di acquisto delle auto elettriche ed ad innovazioni tecnologiche che aumentano l’autonomia delle batterie. Sono state prese in considerazione 7 tipologie di automobili, appartenenti prevalentemente alla Classe B. Ad ogni persona è stato sottoposto un questionario e degli esercizi di scelta ipotetica. Le risposte ottenute hanno permesso di stimare un modello di scelta discreta di tipo mixed logit e di elaborare un modello di simulazione. Le simulazioni indicano che le preferenze dei consumatori tra i 7 modelli considerati vedono con maggior favore soprattutto la Ford Fiesta (diesel) (72,9% come prima scelta) e, in seconda battuta, la Toyota Yaris (ibrida - benzina) con il 18,6% come prima scelta ed il 71,6% come seconda scelta. Le automobili elettriche - la Peugeot Ion (elettrica con batteria di proprietà) e la Renault Zoe (elettrica con batteria a noleggio) - si attestano attorno ad un promettente 6,5% come prima scelta, con una preferenza per quelle con batteria di proprietà. L’introduzione del contributo statale per l’acquisto di auto a basse emissioni e il probabile aumento dell’autonomia delle automobili elettriche rovesciano l’ordinamento di preferenza: la Toyota Yaris (ibrida - benzina) diventa la scelta preferita seguita dalla Ford Fiesta (diesel), mentre le auto elettriche crescono fino ad arrivare in qualche scenario a circa il 12%. Solo in uno scenario estremamente favorevole alle automobili elettriche con la presenza congiunta del contributo statale e dell’eventuale aumento del prezzo dei carburanti di origine fossile o di un’ulteriore diminuzione di 5.000€ del prezzo delle automobili elettriche, eventualmente reso possibile dalla diminuzione dei prezzi delle batterie o dal godimento delle economie di scala, le automobili elettriche raggiungono un significativo livello che si attesta a circa il 24% come prima scelta. |
| Date: | 2013 |
| URL: | http://d.repec.org/n?u=RePEc:sit:wpaper:13_04&r=dcm |
| By: | Jong-Hee Hahn (Yonsei University); Yun Jeong Choi (Yonsei University); Jinsoo Bae (Ohio State University) |
| Abstract: | This paper investigates whether fixed and mobile broadband services are substitutes or complements using firm-level panel data obtained from three major telecommunications operators in South Korea. We employ a multi-level demand model based on Hausman et al. (1994), which allow for the possibility of complementarity between differentiated services. The estimated price elasticities of demand indicate that mobile broadband is a (week) substitute for fixed broadband while fixed broadband is complementary to mobile broadband. This is in contrast with the previous studies based on logit models which essentially assume substitution between different technologies. This result implies that fixed and mobile internet services constitute distinctive antitrust markets at least in the early stage of mobile broadband development. |
| Keywords: | Mobile broadband, Fixed broadband, Substitution, Complementarity, Multi-level demand model. |
| Date: | 2014–07 |
| URL: | http://d.repec.org/n?u=RePEc:yon:wpaper:2014rwp-68&r=dcm |
| By: | W. Robert Reed (University of Canterbury); Raymond J.G.M. Florax; Jacques Poot |
| Abstract: | This study uses Monte Carlo analysis to investigate the performances of five different meta-analysis (MA) estimators: the Fixed Effects (FE) estimator, the Weighted Least Squares (WLS) estimator, the Random Effects (RE) estimator, the Precision Effect Test (PET) estimator, and the Precision Effect Estimate with Standard Errors (PEESE) estimator. We consider two types of publication bias: publication bias directed against statistically insignificant estimates, and publication bias directed against wrong-signed estimates. Finally, we consider three cases concerning the distribution of the “true effect”: the Fixed Effects case, where there is only estimate per study, and all studies have the same true effect; the Random Effects case, where there is only one estimate per study, and there is heterogeneity in true effects across studies; and the Panel Random Effects case, where studies have multiple estimates, and true effects are random both across and within studies. Our simulations produce a number of findings that challenge results from previous research. |
| Keywords: | Meta-analysis, Random effects, Fixed effects, publication bias, Monte Carlo, Simulations |
| JEL: | B41 C15 C18 |
| Date: | 2014–08–13 |
| URL: | http://d.repec.org/n?u=RePEc:cbt:econwp:14/22&r=dcm |
| By: | Dasgupta, Utteeyo; Gangadharan, Lata; Maitra, Pushkar; Mani, Subha |
| Abstract: | The goal of this paper is to examine stability in preferences using the Stigler- Becker state-dependent framework. Using a randomized intervention that changes the opportunity sets of individuals we construct a unique panel data from an artefactual field experiment and evaluate whether the change in the state space influences our selected indicators of preferences: risk, competitiveness, and confidence. We find that there is considerable heterogeneity of preferences across individuals at a point in time; risk and competitive preferences inter-temporally are consistent with state-dependent preferences, while measures of confidence seem to depend on past experiences. |
| Keywords: | Preference stability, State Contingent Preferences, Artefactual Field Experiment |
| JEL: | C9 D01 D03 |
| Date: | 2014–08–18 |
| URL: | http://d.repec.org/n?u=RePEc:pra:mprapa:58010&r=dcm |
| By: | Marinho Bertanha; Petra Moser |
| Abstract: | Count data regressions are an important tool for empirical analyses ranging from analyses of patent counts to measures of health and unemployment. Along with negative binomial, Poisson panel regressions are a preferred method of analysis because the Poisson conditional fixed effects maximum likelihood estimator (PCFE) and its sandwich variance estimator are consistent even if the data are not Poisson-distributed, or if the data are correlated over time. Analyses of counts may be affected by correlation in the cross-section. For example, patent counts or publications may increase across related research fields in response to common shocks. This paper shows that the PCFE and its sandwich variance estimator are consistent in the presence of such dependence in the cross-section - as long as spatial dependence is time-invariant. In addition to the PCFE, this result also applies to the commonly used Logit model of panel data with fixed effects. We develop a test for time-invariant spatial dependence and provide code in STATA and MATLAB to implement the test. |
| JEL: | C23 C33 O3 |
| Date: | 2014–08 |
| URL: | http://d.repec.org/n?u=RePEc:nbr:nberwo:20374&r=dcm |
| By: | Craig A. Gallet; Hristos Doucouliagos |
| Abstract: | There is much disparity in estimates of the income elasticity of air travel across the literature. We examine this disparity by applying meta-regression techniques. Controlling for several issues, including publication selection bias, while our preferred baseline income elasticity estimate of 1.186 is consistent with air travel being a luxury and a slightly immature market, there are several features of the literature which sway the income elasticity away from this baseline. For instance, the income elasticity increases to 1.546 on international routes, yet decreases to 0.633 when air fare is included in a dynamic specification of demand, ceteris paribus. Other characteristics of the literature, such as those involving various data and estimation choices, have less influence on the reported income elasticity. |
| Keywords: | income elasticity, air travel, meta-regression analysis |
| Date: | 2014–08–12 |
| URL: | http://d.repec.org/n?u=RePEc:dkn:econwp:eco_2014_6&r=dcm |