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We present Bayesian models for finding the longitudinal causal effects of a randomized two-arm training program when compliance with the randomized assignment is less than perfect in the training arm (but perfect in the non-training arm) for reasons that are potentially correlated with the outcomes. We deal with the latter confounding problem under the principal stratification framework of Sommer and Zeger (1991) and Frangakis and Rubin (1999), and others. Building on the Bayesian contributions of Imbens and Rubin (1997), Hirano et al. (2000), Yau and Little (2001) and in particular Chib (2007) and Chib and Jacobi (2007, 2008), we construct rich models of the potential outcome sequences (with and without random effects), show how informative priors can be reasonably formulated, and present tuned computational approaches for summarizing the posterior distribution. We also discuss the computation of the marginal likelihood for comparing various versions of our models. We find the causal effects of the observed intake from the predictive distribution of each potential outcome for compliers. These are calculated from the output of our estimation procedures. We illustrate the techniques and ideas with data from the 1994 JOBS II trial that was set up to test the efficacy of a job training program on subsequent mental health outcomes.

In an evaluation of a job training program, the causal effects of the program on wages are often of more interest to economists than the program's effects on employment or on income. The reason is that the effects on wages reflect the increase in human capital due to the training program, whereas the effects on total earnings or income may be simply reflecting the increased likelihood of employment without any effect on wage rates. Estimating the effects of training programs on wages is complicated by the fact that, even in a randomized experiment, wages are truncated by nonemployment, i.e., are only observed and well-defined for individuals who are employed. We present a principal stratification approach applied to a randomized social experiment that classifies participants into four latent groups according to whether they would be employed or not under treatment and control, and argue that the average treatment effect on wages is only clearly defined for those who would be employed whether they were trained or not. We summarize large sample bounds for this average treatment effect, and propose and derive a Bayesian analysis and the associated Bayesian Markov Chain Monte Carlo computational algorithm. Moreover, we illustrate the application of new code checking tools to our Bayesian analysis to detect possible coding errors. Finally, we demonstrate our Bayesian analysis using simulated data.

Based on a continuous version of the Lanchester advertising model for a duopoly, a mathematical model is developed to determine the optimal advertising policy of a firm responding to the advertising pulsation policy of its competitor. A Dynamic Programming (DP) approach has been employed to arrive at the optimal solution.

It has been mainly demonstrated that under a concave or linear advertising response function, the focal firm's DP policy is superior to its Uniform Advertising Policy (UAP) counterpart (constant advertising spending over time), irrespective of the advertising pulsation policy employed by its rival. Under a convex advertising response function, on the other hand, the focal firm's DP policy is superior to its Advertising/Maintenance Pulsing Policy (APMP) and Advertising Pulsing Policy (APP) counterparts (alternating advertising spending at two levels), irrespective of the advertising pulsation policy used by the competitor.

The strength of personal selling lies in the fact that it allows for communicative interchange, a process more subtle but, at the same time, more hazardous than classical methods such as advertising, which rely on one‐way communication. In terms of efficiency, communicative interchange results in a reduction of reach losses; it is of primary importance in the marketing of commodities which have to be explained or demonstrated to the buyer and particularly, therefore, in industrial marketing and the marketing of services. It is recognised, however, that personal selling is a relatively expensive means of communication.The author undertakes a taxonomical review of the various constituents of the personal selling scene, analysing the tasks involved and the composition of the sales force. In the latter half of the monograph he selects certain sales force management problems of special importance to discuss in greater detail with regard to the optimisation of efficiency and job statisfaction.

This article examines the history, development, and application of the sandwich estimate of variance. In describing this estimator, we pay attention to applications that have appeared in the literature and examine the nature of the problems for which this estimator is used. We describe various adjustments to the estimate for use with small samples, and illustrate the estimator’s construction for a variety of models. Finally, we discuss interpretation of results.

In China, private equity placement (PEP) has become the most important equity refinancing method because most listed firms issue new stocks in this method. However, previous literature has not paid much attention to the impact of political connections on PEP. In this paper, the authors aim to focus on the effect of ultimate ownership types and political connections on approval, approval time, approval results and proceeds of PEP. Besides that the authors also explore the influence of different types and levels of political connections on PEP.

This study investigates the impact of ultimate ownership and political connections of private firms on the approval of PEPs. The authors obtain a final sample of 1,651 private placement events of Chinese-listed firms. To test the hypothesis that the authors developed in this paper, the authors use empirical models from the existing literature about political connections and corporate finance. They establish multiple linear regressions to test Hypothesis 1 and 3 and introduce a logit model to test Hypothesis 2.

First, this study documents that state-owned firms have significant advantages over private firms in approval procedure. Second, political connections seem to help private firms obtain approval of placements from China Securities Regulatory Commission. Third, political connections through government officers are not useful for firms to obtain refinance resources, whereas the connections of being members of Chinese People’s Political Consultative Conference and People’s Congress are the two valuable types of political connections to help private firms obtain approval.

This paper has three main contributions to the previous literature. The first contribution is to provide an evidence for the relation between political connections and PEP approval procedures. The second contribution is to provide a comparison between government officer’s connection and social title’s connection. The third contribution of this paper is to reveal the influence of non-disclosed political connection on PEP approval. All the three contributions are important for understanding the relation between political connections and firm refinancial policy.

This chapter presents first a theoretical model of conflict between two agents characterised by a two-sector economy. In a contested sector, two agents struggle to appropriate the maximum possible fraction of a contestable output. In an uncontested sector, they hold secure property rights over the production of some goods. Agents split their resource endowment between ‘butter’, ‘guns’ and ‘ice-cream’. Eventually, tradable goods made of both butter and ice-cream produced by conflicting parties are sold to the rest of the world. Therefore, the opportunity cost of conflict depends also on the relative profitability of contested and uncontested production. In particular, productivity of uncontested production and profitability of contested sectors are countervailing forces. The empirical section focused on a panel of Sub-Saharan African countries for the period 1995–2006. Results are not fully conclusive. However, there is robust evidence that prices of manufactures (interpreted as the uncontested ice-cream) are negatively associated with the likelihood of a civil war. Eventually, international price of manufactures is also associated with a higher GDP per capita growth rate. The concluding remark seems to be that an increase in world prices of manufactures would make civil wars less likely.

The relevant basic principle for overall distribution in macrojustice turns out to be the relevant equality of liberties. This study shows the consequence of this fact for the optimum distribution, taxation, and transfers of income. The liberties in question are social liberty (freedom from forceful interference, basic rights), and the possibilities offered by domains of choice which can provide equal liberty while being different for individuals with different productivities.

The method is deductive from the basic relevant concepts.

The result is that this distribution consists of an equal sharing of the proceeds of the same labour for all individuals (with their different productivities). The individuals choose freely their total labour (with no other tax). This redistributive structure is Equal-Labour Income Equalization or ELIE. It also has a number of other important meanings, such as: general balanced labour reciprocity (each yields to each other the proceeds of the same labour); equal basic universal income financed by an equal labour of all; and uniform linear concentration to the mean of the distribution of total incomes (including the value of leisure).

This result extends to multidimensional labour (duration, education, intensity, etc.), and to partial labour including unemployments.

The practical application relies on exemption of overtime labour from the income tax, and a tax credit. This is successfully applied in some countries.

This constitutes a new paradigm of optimum income distribution and taxation. The old paradigm was based on welfarism not found relevant by society for this application, and it has therefore never been applied.

Equilibrium is an important problem in mathematical economics. The paper deals with the problem by establishing pansystems models of equilibrium and introducing ε‐equilibrium solutions. Under the framework of these models, we discuss the existence of equilibrium solution and the ranges where prices, demand and supply commodities vary, respectively.

This chapter attempts to explicitly integrate the idea of reference group when measuring relative deprivation. It assumes that in assessing his situation in society an individual compares himself with individuals whose environment can be considered as being similar to his. By environment we mean the set of people with a similar set of observable characteristics such as human capital, household attributes, and location. We therefore propose to measure relative deprivation by comparing the actual income of an individual with the one he could have expected on the basis of the level of these characteristics. We then aggregate these individual comparisons by computing an index of “distributional change” that compares, on a non anonymous basis, the distributions of the actual and “expected” incomes. At the difference of other approaches to relative deprivation, our measure takes into account not only the difference between the actual and “expected” individual incomes but also that between the actual and “expected” individual ranks. We applied our approach to Moldova, the poorest country in Europe, using a survey that covered a period of six years (from 2000 to 2005). We then observed that our measure of deprivation is well suited to study wage deprivation across genders and is able to proxy subjective deprivation in living standards reported by survey respondents better than conventional measures of relative deprivation.