Florenz Plassmann

DOES THE RIGHT TO CARRY CONCEALED HANDGUNS DETER COUNTABLE CRIMES? ONLY A COUNT ANALYSIS CAN SAY*

An analysis of the effects of right‐to‐carry laws on crime requires particular distributional and structural considerations. First, because of the count nature of crime data and the low number of expected instances per observation in the most appropriate data, least‐squares methods yield unreliable estimates. Second, use of a single dummy variable as a measure of the nationwide effect of right‐to‐carry laws is likely to introduce geographical and intertemporal aggregation biases into the analysis. In this paper, we use a generalized Poisson process to examine the geographical and dynamic effects of right‐to‐carry laws on reported homicides, rapes, and robberies. We find that the effects of such laws vary across crime categories, U.S. states, and time and that such laws appear to have statistically significant deterrent effects on the numbers of reported murders, rapes, and robberies.

Preferences, Technology, and the Environment: Understanding the Environmental Kuznets Curve Hypothesis

We derive a simple expression for the income-pollution path using the standard static model of the environmental Kuznets curve (EKC). This expression makes it straightforward to identify the general characteristics of utility and pollution functions that lead to such a curve. We show that suitable preferences can always lead to an EKC while there is no technology that yields an EKC for all types of preferences, and we derive a sufficient condition for technology that leads to an EKC for almost all types of preferences. Our results hold for a model with multiple goods with different pollution intensities and for a production economy with nonconstant relative price of consumption and environmental effort. We derive our results without assuming specific functional forms and we encompass several other models as special cases.

Household Income and Pollution Implications for the Debate About the Environmental Kuznets Curve Hypothesis

Country-level analyses of global Environmental Kuznets Curve (EKC) relationships that use multicountry panel data sets are likely to suffer from several types of aggregation bias that may explain why previous studies have yielded conflicting results. The authors analyze 1990 cross-sectional data for the United States for three pollutants and test the general EKC relationship as well as the pure income effect. Their results suggest that the income level at which households reduce their exposure to pollution depends on the nature of the pollutant. They find consistent evidence for such a relationship for coarse particulate matter but little evidence for nonmonotonic relationships for carbon monoxide and ground-level ozone.

Assessing the Precision of Turning Point Estimates in Polynomial Regression Functions

Researchers often report point estimates of turning point(s) obtained in polynomial regression models but rarely assess the precision of these estimates. We discuss three methods to assess the precision of such turning point estimates. The first is the delta method that leads to a normal approximation of the distribution of the turning point estimator. The second method uses the exact distribution of the turning point estimator of quadratic regression functions. The third method relies on Markov chain Monte Carlo methods to provide a finite sample approximation of the exact distribution of the turning point estimator. We argue that the delta method may lead to misleading inference and that the other two methods are more reliable. We compare the three methods using two data sets from the environmental Kuznets curve literature, where the presence and location of a turning point in the income-pollution relationship is the focus of much empirical work.

Accurate Valuation in the Absence of Markets

Incomplete markets do not provide accurate information about peoples subjective valuations of goods. Knowledge of these subjective valuations is often important, however, for example when compensation payments for damaged or destroyed property are required. We argue that in such cases, an attractive measure of the value of a good is the reservation price of the owner, who is generally the person who values it most highly. If a property is sufficiently unique so that there is no market price that can be used as an approximation, then the only way to learn this subjective reservation price is to have the owner self-assess his property. We describe a mechanism that provides an incentive for the owner to self-assess his property honestly without requiring that the propertys value be objectively observable.

A note on ‘the simple analytics of the Environmental Kuznets Curve’

In a widely cited paper, Andreoni and Levinson (2001) argue that, under very mild restrictions on preferences, increasing returns to scale in pollution abatement are a sufficient condition for pollution to ultimately fall to zero with income growth. We show that the existence of an Environmental Kuznets Curve depends on the relative magnitudes of the returns to scale in abatement and in gross pollution, rather than on their absolute values. Increasing returns to scale in abatement by themselves are not sufficient for pollution to fall with income unless the returns to scale of abatement exceed the returns to the production of gross pollution. ∗ Corresponding author. We thank the journal editor and three anonymous reviewers for their comments on an earlier draft. All errors are ours. Summary Andreoni and Levinson (2001) argue that, under very mild restrictions on preferences, increasing returns to scale in pollution abatement are a sufficient condition for pollution to ultimately fall to zero with income growth. Their paper has received considerable attention in the environmental economics literature: as of April 2005, the Social Science Citation Index shows 17 publications that cite this paper. They suggest (p.284) that “simple explanations regarding the technology of production and abatement could be central to understanding the phenomenon” of the Environmental Kuznets Curve (EKC). We show that their result is driven by their particular choice of the functional relationship between consumption and gross pollution, and that abatement technology is much less important in a generalized model. The impact of the technology of production and abatement on the existence of an EKC is therefore likely to be smaller than suggested, and an increased focus on technology may not add as much to our understanding of the EKC as Andreoni and Levinson envisage. Andreoni and Levinson derive their main theorem under the assumption that consumption and gross pollution are directly proportional. However, even if the relationship between consumption and gross pollution is indeed linear, such a one-to-one correspondence depends on the units in which consumption and pollution are measured. It is also possible that the true relationship is non-linear. We extend Andreoni and Levinson’s model by permitting a general relationship between consumption and gross pollution. We show that increasing returns to scale in abatement by themselves are not sufficient for pollution to fall with income, and that the existence of an EKC depends on the relative magnitudes of the returns to scale in abatement and in gross pollution, rather than on their absolute values. Our analysis indicates that there is nothing special about increasing returns to scale in abatement, and that even under decreasing returns to scale in abatement, pollution will eventually decline to zero as income increases as long as the returns to scale in gross pollution are less than the returns to scale in abatement. Our result suggests that pollution reduction at source (generation) is just as important as end-of-pipe type abatement efforts, and that empirical evidence of increasing returns to scale in abatement does not imply anything about the income-pollution path.

A comparison of theoretical and empirical evaluations of the Borda Compromise

The Borda Compromise states that, if one has to choose among five popular voting rules that are not Condorcet consistent, one should always give preference to the Borda rule over the four other rules. We assess the theoretical as well as the empirical support for the Borda Compromise. We find that, despite considerable differences between the properties of the theoretical framework and the characteristics of two sets of observed ranking data, all three analyses provide considerable support for the Borda Compromise.

Should voters be required to rank candidates in an election

We compare the Condorcet Efficiencies of the plurality rule, the negative plurality rule, and the Borda rule to address the question of what might be gained by using a voting rule that requires candidate rankings. Unlike previous analyses, we consider only those voting situations for which the three rules determine different candidates as winners, because these are the cases where the Condorcet Efficiencies might actually differ across the three rules. After assessing the theoretical as well as the empirical Condorcet Efficiencies, we find that, despite considerable differences between the properties of the theoretical framework and the characteristics of three sets of empirical ranking data, all four analyses suggest that there is a considerable benefit in asking voters to submit candidate rankings.

The Welfare Analysis of a Free Trade Zone: Intermediate Goods and the Asian Tigers

We analyse trade reform among the ASEAN countries, which recently began removing all mutual trade barriers. The standard method to avoid complete specialisation in traded goods is to distinguish goods both by physical type and place of origin (the so-called Armington assumption). This methodology is not suitable for the sort of intermediate goods produced by the ASEAN countries. We develop a computational approach in the context of a non-Armington dynamic general equilibrium model. Analysing the results of a calibrated version of the model, we find that trade liberalisation is generally welfare improving for the ASEAN countries.

Developing the aggregate empirical side of computational social choice

The aggregate empirical side of computational social choice has received relatively little attention. This paper provides a progress report on our on-going research project on statistical characterizations of the outcomes of vote-casting processes. We describe a statistical model that is capable of generating voting situations for three-candidate elections that have a distribution very similar to that of observed voting situations. We show that our simulated voting situations can provide interesting insights into the question of which voting rule is most likely to identify the best candidate.