MSE-improvement of the least squares estimator by dropping variables

It is well known that dropping variables in regression analysis decreases the variance of the least squares (LS) estimator of the remaining parameters. However, after elimination estimates of these parameters are biased, if the full model is correct. In his recent paper, Boscher (1991) showed that the LS-estimator in the special case of a mean shift model (cf. Cook and Weisberg, 1982) which assumes no “outliers” can be considered in the framework of a linear regression model where some variables are deleted. He derived conditions under which this estimator outperforms the LS-estimator of the full model in terms of the mean squared error (MSE)-matrix criterion. We demonstrate that this approach can be extended to the general set-up of dropping variables. Necessary and sufficient conditions for the MSE-matrix superiority of the LS-estimator in the reduced model over that in the full model are derived. We also provide a uniformly most powerful F-statistic for testing the MSE-improvement.     

Industrial relations in the next decade

Here the authors discuss current trends in British industrial relations and their likelihood of continuing. The central question is that of the probable consequences for management and unions of the sustained rise in unemployment.     

Strategy-proofness and Arrow's conditions: Existence and correspondence theorems for voting procedures and social welfare functions

Consider a committee which must select one alternative from a set of three or more alternatives. Committee members each cast a ballot which the voting procedure counts. The voting procedure is strategy-proof if it always induces every committee member to cast a ballot revealing his preference. I prove three theorems. First, every strategy-proof voting procedure is dictatorial. Second, this paper's strategy-proofness condition for voting procedures corresponds to Arrow's rationality, independence of irrelevant alternatives, non-negative response, and citizens' sovereignty conditions for social welfare functions. Third, Arrow's general possibility theorem is proven in a new manner.     

On the human aspects in structural modeling

This article deals with two facets of structural modeling often ignored: a) the several human roles that effective participative modeling must encompass, and b) the group procedures developed to assist modelers in defining the elements of the system to be modeled. The roles are 1) the method technician, 2) the facilitator, and 3) the participant. Their recognition on the part of the technology assessment leader is vital to the successful conduct of participative modeling. The element-generating group procedures surveyed here are organized into two categories: those which emphasize an atmosphere for free-wheeling thinking, and those which emphasize structured guidance (either through use of words or geometric and analytic techniques).     

Corporate financial structure and the funding of private pension plans

One strand of the literature on the employment contract focuses on the role of the contract in the efficient sharing of risk between capitalists and workers. One way capitalists can shift risk to workers is to provide part of workers' remuneration in the form of an unfunded, deferred pension. Since bonds, in the event of bankruptcy or voluntary termination, are typically senior to unfunded pension liabilities, capitalists can also affect their risk by altering the firm's debt-to-equity ratio. These observations suggest that corporate financial structure and the employment contract are interdependent. The paper has two major goals. The first is to take a step towards integrating the theory of corporate financial structure with that of the employment contract. The second is to investigate possible consequences of legislation which regulates the funding of private pensions.     

On the theory of macroeconomic quasi-equilibria

Conclusion It has been shown that for the Classical System a quasi-equilibrium cannot exist, unless we make the ad hoc assumption of inflexible nominal wages⁸. The equilibrium in the classical regime corresponds to the general competitive equilibrium, and of course the validity of Walras' Law cannot be questioned. At the same time, however, it has been shown that to extend these conclusions to the Keynesian system as well is not justified. The Keynesian system has, in general, a quasi-equilibrium. The model constructed in this paper and the resulting conclusions are significant because the model: (a) Incorporates the Keynesian notion of effective demand, which includes the demand for capital goods (investment) as being performed by a group of people distinct from the consumers (and so, answering Negishi's point, there is a prince in Hamlet!), (b) Unlike other models (like the recent paper by Glustoff), it does not rely on nominal wage rigidity to explain unemployment, but instead, again answering Negishi's remark, it explains rather than postulates why real wages do not adjust in the presence of unemployment so as to eliminate it. (c) It verifies the validity of Clower's proposition that in the Keynesian System Walras' Law holds only in equilibrium. (d) It reconsiles Bent Hansen's original quasi-equilibrium model with the Keynesian proposition of an unemployment equilibrium, against the apparent view of Hansen that to do that would require the assumption of a Phillips curve, a view also shared by Arrow and Hahn, and many others.An earlier version of this paper was presented in the December 1974 meeting of the Econometric Society in San Francisco. The author wishes to thank Prof. R. Clower, Prof. B. Hansen, Prof. S. Black, and Dr. G. Winckler for their valuable comments, but he obviously claims any errors for himself.     

Putting supplies at the bedside via the Friesen concept

Hospitals designed using the concepts of architect Gordon Friesen are especially conducive to reengineering for patient-focused care. The Nurserver, a closet-like space outside each patient's room, makes it very easy for hospitals to redesign their methods for delivering supplies so that caregivers seldom have to go more than a few feet to get what they need. In this article, staff of Monongalia General Hospital in Morgantown, West Virginia, describe how they have used the Friesen design to modify supply distribution processes.