Cyclical Double-Auction Markets With and Without Speculators

This study reports the results of 18 computerized \u27double-auction\u27 market experiments characterized by cycling excess demand. Two such market designs are studied: one with stationary supply and cycling demand, the other with cycling supply and demand. Data from a series of control experiments under conditions of intertemporal isolation (autarky) are compared with data from experiments where the two cyclical market phases are linked by a subset of agents (speculators). Allowing intertemporal speculation is found to be a significant treatment variable in both market designs; however, price convergence patterns are not robust with respect to the design change

Matching Contributions and the Voluntary Provision of a Pure Public Good: Experimental Evidence

Laboratory experiments are used to study the voluntary provision of a pure public good in the presence of an anonymous external donor. The external funds are used in two different settings, lump-sum matching and one-to-one matching, to examine how allocations to the public good are affected. The experimental results reveal that allocations to the public good under lumpsum matching are significantly higher, and have significantly lower within-group dispersion, relative to one-to-one matching and a baseline setting without external matching funds.public goods, free riding, laboratory experiments

Tests of rational expectations in a stark setting

Rational expectations (Economic theory)

The effects of problem-oriented policing on crime and disorder

Problem-oriented Policing (POP) was first introduced by Herman Goldstein in 1979. The approach was one of a series of responses to a crisis in effectiveness and legitimacy in policing that emerged in the 1970s and 1980s. Goldstein argued that police were not being effective in preventing and controlling crime because they had become too focused on the “means” of policing and had neglected the “goals” of preventing and controlling crime and other community problems. Goldstein argued that the unit of analysis in policing must become the “problem” rather than calls or crime incidents as was the case during that period. POP has had tremendous impact on American policing, and is now one of the most widely implemented policing strategies in the US. To synthesize the extant problem-oriented policing evaluation literature and assess the effects of problem-oriented policing on crime and disorder Eligible studies had to meet three criteria: (1) the SARA model was used for a problemoriented policing intervention; (2) a comparison group was included; (3) at least one crime or disorder outcome was reported with sufficient data to generate an effect size. The unit of analysis could be people or places. Several strategies were used to perform an exhaustive search for literature fitting the eligibility criteria. First, a keyword search was performed on an array of online abstract databases. Second, we reviewed the bibliographies of past reviews of problem-oriented policing. Third, we performed forward searches for works that have cited seminal problem-oriented policing studies. Fourth, we performed hand searches of leading journals in the field. Fifth, we searched the publications of several research and professional agencies. Sixth, after finishing the above searches we e-mailed the list of studies meeting our eligibility criteria to leading policing scholars knowledgeable in the area of problem-oriented policing to ensure we had not missed any relevant studies. For our ten eligible studies, we provide both a narrative review of effectiveness and a meta-analysis. For the meta-analysis, we coded all primary outcomes of the eligible studies and we report the mean effect size (for studies with more than one primary outcome, we averaged effects to create a mean), the largest effect, and the smallest effect. Because of the heterogeneity of our studies, we used a random effects model. Based on our meta-analysis, overall problem-oriented policing has a modest but statistically significant impact on reducing crime and disorder. Our results are consistent when examining both experimental and quasi-experimental studies. Conclusions: We conclude that problem-oriented policing is effective in reducing crime and disorder, although the effect is fairly modest. We urge caution in interpreting these results because of the small number of methodologically rigorous studies on POP and the diversity of problems and responses used in our eligible studies

The Formation of Price Forecasts in Experimental Markets.

This study utilizes laboratory experimental methods to evaluate the empirical validity of: (1) "Muthian" rational expectations assumptions, (2) an adaptive expectations model, and (3) an extrapolative expectations model. Over 5 00 price forecasts from 146 participants in twelve experimental double-auction m arkets with a cash reward structure are analyzed. The forecasting objective is t hemean price over a sequence of trading periods governed by stationary market parameters. The price forecasts are found to be inconsistent with strict Muthian rational expectations and the extrapolative modelis not supported by the data. However, the forecasts generally support the adaptive expectations model. Copyright 1987 by Ohio State University Press.