Effectiveness of Ninth-Grade Physics in Maine: Conceptual Understanding

The Physics First movement - teaching a true physics course to ninth grade students - is gaining popularity in high schools. There are several different rhetorical arguments for and against this movement, and it is quite controversial in physics education. However, there is no actual evidence to assess the success, or failure, of this substantial shift in the science teaching sequence. We have undertaken a comparison study of physics classes taught in ninth- and 12th grade classes in Maine. Comparisons of student understanding and gains with respect to mechanics concepts were made with excerpts from well-known multiple-choice surveys and individual student interviews. Results indicate that both populations begin physics courses with similar content knowledge and specific difficulties, but that in the learning of the concepts ninth graders are more sensitive to the instructional method used.Comment: 15 pages, 2 tables, 0 figures, to be published in The Physics Teache

Adverse Selection plus Strategic Advantageous Selection Equals Trade

In this paper we apply a learning model from machine learning, to a human trading crowd to understand why the no trade theorem was rejected. Our results reveal that trading volume in a continuous double auction market is associated with inverse learning curves. Inverse learning results from adverse selection among market takers and strategic advantageous selection among market makers. In contrast to associating adverse selection with market failure in traditional competitive market theory, the rules of a double auction market efficiently exploit individual differences among the trading crowd to generate both large amounts of trading volume and relatively efficient prices.

The Effectiveness of Britain's Financial Service Authority: An Economic Analysis

Sweeping regulatory reforms in Britain resulted in the formation of the Financial Services Authority (FSA). Because greater transparency of information is a major objective for this Act, shifting from one information system to another has re-distributive effects. We identify these effects at a sector level and their drivers at the firm level. At a sector level, FSA has generally increased the precision of investors’ priors reducing the information risk component of the cost of capital. At a firm level, large firms act as “Stackelberg leaders” in voluntary disclosure games. FSA regulation shifts power from leaders to “followers”.Disclosure, Regulation, Game Theory, Stackelberg Leader, Cost of Capital: information asymmetry

Measuring the Impact of Regulationon Market Stability: Evidence from the US Markets

In this paper, we introduce a new methodology designed to test the effect of new regulatory disclosure requirements on the disclosure threshold as predicted by the extant literature (Verrecchia (1983), Dye (1985)). We apply our methodology to test the consistency between observed effects from major US regulation past and present (1933/1934 Securities Acts, Regulation Fair Disclosure 2000, and the Sarbanes-Oxley Act 2002) with regulatory objectives.

Ductile fracture mechanisms in carbon manganese steel weld metals

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The Financial Services Reform Act 2001: Impact on Systemic risk in Australia

The rise of conglomerate banks and their interrelated balance sheets, pose new challenges to theories of financial regulation. We measure the impact of recent legislative changes in Australia upon systemic risk, for banking and near banking sectors, and demonstrate a significant reduction post the legislation. This is consistent with a major legislative goal, to promote global competitiveness, because it implies a reduction in the cost of equity capital. In addition, we find no evidence in support of the HIH collapse increasing systemic risk in the overall financial sector but a relatively small effect was detected in the banking sector.Ris, Banks, Disclosure, Regulation, Entropy

Imputation Estimators Partially Correct for Model Misspecification

Inference problems with incomplete observations often aim at estimating population properties of unobserved quantities. One simple way to accomplish this estimation is to impute the unobserved quantities of interest at the individual level and then take an empirical average of the imputed values. We show that this simple imputation estimator can provide partial protection against model misspecification. We illustrate imputation estimators' robustness to model specification on three examples: mixture model-based clustering, estimation of genotype frequencies in population genetics, and estimation of Markovian evolutionary distances. In the final example, using a representative model misspecification, we demonstrate that in non-degenerate cases, the imputation estimator dominates the plug-in estimate asymptotically. We conclude by outlining a Bayesian implementation of the imputation-based estimation.Comment: major rewrite, beta-binomial example removed, model based clustering is added to the mixture model example, Bayesian approach is now illustrated with the genetics exampl