Using an approximate kiefer-weiss solution for testing insect population densities

Summary A sequential testing procedure called 2-SPRT for the meanμ of the negative binomial distribution with known exponentk is presented. For any fixedμ ₀(μ ₁<μ ₀<μ ₂), the 2-SPRT provides an asymptotic solution to the modified Kiefer-Weiss problem. Determination ofμ ₀ such that the test provides an approximate solution to the Kiefer-Weiss problem is described. The behavior of the 2-SPRT and the Sequential Probability Ratio Test is investigated using Monte Carlo methods. The error probabilities and the average sample numbers are compared. All the computations were carried out on the Alabama Supercomputer.     

Action Teams That Work

A growing awareness of workplace hazards and identification of airborne contaminants, coupled with a changing safety and health regulatory environment, created an unexpected demand for new and innovative respirators in the early 1980s. 3M's Occupational Health and Environmental Safety Division broke new ground by taking the team concept further than ever before in the company. The division's Action Teams successfully designed, built and introduced products in less than half the time it would have taken previously. Robert Hershock, Charles Cowman and Douglas Peters describe how 3M learned important lessons about team selection, training, performance and motivation, the importance of project sponsors, and the role of middle management.     

Airbus versus Boeing revisited: international competition in the aircraft market

This paper examines international competition in the commercial aircraft industry. We estimate a discrete choice, differentiated products demand system for wide-body aircraft and examine the Airbus-Boeing rivalry under various assumptions on firm conduct. We then use this structure to evaluate two trade disputes between the United States and European Union. Our results suggest that aircraft prices increased by about 3.7% after the 1992 US-EU agreement on trade in civil aircraft that limits subsidies. This price hike is consistent with a 5% increase in firms' marginal costs after the subsidy cuts. We also simulate the impact of the future entry of the Airbus A-380 super-jumbo aircraft on the demand for other wide-bodied aircraft, notably the Boeing 747. We find that the A-380 could reduce the market share of the 747 by up to 14.8 percentage points in the long-range wide-body market segment (depending upon the discounts offered on the A-380), but would reduce the market for Airbus's existing wide-bodies by an even greater margin.     

Managerial Equity Ownership and the Demand for Outside Directors

This paper examines the linkage between the use of outside directors and managerial ownership. We conjecture there are two linkages: the standard incentive‐alignment demand for monitoring when managers own little stock and an entrenchment‐amelioration demand when managerial stock ownership is high. As a consequence, we predict the association between managerial ownership and board composition will be nonlinear (U‐shaped if the entrenchment effect is sufficiently pronounced). Using UK data, we find that both quadratic and logarithmic models outperform the simple linear relationship assumed in prior research and that the substitution between managerial ownership and board composition is stronger than hitherto supposed.     

Hard Times or Great Expectations? Dividend Omissions and Dividend Cuts by UK Firms*

This paper uncovers an increasing proportion of quoted UK companies omitting cash dividends. Using a large panel of quoted UK firms, we estimate panel data probit models for the incidence of dividend omissions and cuts as functions of financial characteristics including cash flow, leverage, investment opportunities, investment and company size. These variables account for most of the increase in omission since 1995. There is relatively little evidence to link this to the major tax reform of 1997 that abolished tax refunds on dividend income payable to tax‐exempt institutions. Significant persistence effects indicate companies are slow to adjust their balance sheets through their dividend.     

Improved estimation of portfolio value‐at‐risk under copula models with mixed marginals

Portfolio value‐at‐risk (PVAR) is widely used in practice, but recent criticisms have focused on risks arising from biased PVAR estimates due to model specification errors and other problems. The PVAR estimation method proposed in this article combines generalized Pareto distribution tails with the empirical density function to model the marginal distributions for each asset in the portfolio, and a copula model is used to form a joint distribution from the fitted marginals. The copula–mixed distribution (CMX) approach converges in probability to the true marginal return distribution but is based on weaker assumptions that may be appropriate for the returns data found in practice. CMX is used to estimate the joint distribution of log returns for the Taiwan Stock Exchange (TSE) index and the associated futures contracts on SGX and TAIFEX. The PVAR estimates for various hedge portfolios are computed from the fitted CMX model, and backtesting diagnostics indicate that CMX outperforms the alternative PVAR estimators. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:997–1018, 2006     

Capital structure and the control of managerial incentives

We present a theory of capital structure based on the power of shareholders, bondholders and managers to control the incentive conflicts in large corporations. The manager–owner conflict produces a trade-off between inefficiency in the low state and rents in the high state, and the shareholder–bondholder conflict produces under-investment as in Myers [Journal of Financial Economics 19 (1997) 147]. Since managers and bondholders both prefer more efficient actions in the low state, the two conflicts are interdependent. With risk-less levels of debt, there are no shareholder–bondholder agency costs, but managerial control over the incentive-setting process produces excessive rents. With risky debt, shareholders focus more on returns in the high state so that shareholder–bondholder agency costs increase but managerial rents decrease. Efficient levels of debt holder protection facilitate a reduction in manager–owner agency costs that outweighs shareholder–bondholder agency costs, and are decreasing in firm performance. The results are consistent with the separate empirical results relating control to both compensation and leverage, and suggest how future studies can be integrated.     

Price rigidities and institutional variations in markets with posted prices

Summary Standard laboratory posted-offer markets respond slowly and incompletely to demand shocks. In these one-sided markets, where sellers control the setting of prices, very little information is transmitted via the process of exchange. For this reason, traders have trouble distinguishing randomness in their own experience from changes in market fundamentals. This paper reports the results of twelve laboratory markets conducted to assess whether some common variants to standard posted-offer rules can correct the adjustment deficiences. Although discounting, multiple postings and excess demand information all improve performance, we find that response remains poor, and efficiencies low.Support for this research was provided by the National Science Foundation (SBR 9319842 and SBR 9320044), and the University of Virginia Bankard Fund. Data are archived at FTP address: fido.econlab.arizona.edu. We wish to thank Charles Plott and Shyam Sunder for useful comments on an earlier draft of this paper. The usual disclaimer applies.     

Public Sector Capital and the Production Efficiency of U.S. Regional Manufacturing Industries

This paper applies a stochastic frontier production model with time-varying technical efficiency to investigate the relationship between public capital and technical efficiency. It is based on the proposition that public capital has an effect on actual output by enhancing technical efficiency, thereby reducing the gap between maximum potential output and actual output. Empirical results using panel data from U.S. state manufacturing industries during 1969–86 show that technical efficiencies varied substantially, both between states and between years; variations in technical efficiency are significantly explained by variations in public-sector capital.
JEL Classification Numbers: O20, H54, C23.     

AN EVALUATION OF PROCESS‐ORIENTED SUPPLY CHAIN MANAGEMENT FRAMEWORKS

Supply chain management (SCM) is implemented by integrating corporate functions using business processes within and across companies. Several process‐oriented frameworks for SCM have been proposed but only two of these provide sufficient detail to enable implementation. We evaluate the Supply‐Chain Operations Reference (SCOR) framework and The Global Supply Chain Forum (GSCF) framework using four criteria and identify their relative strengths and weaknesses.