The inverse Banzhaf problem

Let ${\mathcal{F}}Let F{\mathcal{F}} be a family of subsets of the ground set [n] = {1, 2, . . . , n}. For each i ? [n]{i \in [n]} we let p(F,i){p(\mathcal{F},i)} be the number of pairs of subsets that differ in the element i and exactly one of them is in F{\mathcal{F}}. We interpret p(F,i){p(\mathcal{F},i)} as the influence of that element. The normalized Banzhaf vector of F{\mathcal{F}}, denoted B(F){B(\mathcal{F})}, is the vector (B(F,1),...,B(F,n)){(B(\mathcal{F},1),\dots,B(\mathcal{F},n))}, where B(F,i)=\fracp(F,i)p(F){B(\mathcal{F},i)=\frac{p(\mathcal{F},i)}{p(\mathcal{F})}} and p(F){p(\mathcal{F})} is the sum of all p(F,i){p(\mathcal{F},i)}. The Banzhaf vector has been studied in the context of measuring voting power in voting games as well as in Boolean circuit theory. In this paper we investigate which non-negative vectors of sum 1 can be closely approximated by Banzhaf vectors of simple voting games. In particular, we show that if a vector has most of its weight concentrated in k < n coordinates, then it must be essentially the Banzhaf vector of some simple voting game with n − k dummy voters.     

Credit this: how the banks decide your credit score

In February, internet bank Egg announced its decision to cancel the credit cards of 161 000 of its customers. Egg were "not comfortable with the level of risk" that these customers represented. Bank customers are judged by their credit scores. So what is credit scoring? How do lenders assess your creditworthiness? And how can you improve your credit score with them? David Edelman provides some answers.     

FAIR DIVISION OF INDIVISIBLE ITEMS

This paper analyzes criteria of fair division of a set of indivisible items among people whose revealed preferences are limited to rankings of the items and for whom no side payments are allowed. The criteria include refinements of Pareto optimality and envy-freeness as well as dominance-freeness, evenness of shares, and two criteria based on equally-spaced surrogate utilities, referred to as maxsum and equimax. Maxsum maximizes a measure of aggregate utility or welfare, whereas equimax lexicographically maximizes persons' utilities from smallest to largest. The paper analyzes conflicts among the criteria along with possibilities and pitfalls of achieving fair division in a variety of circumstances.     

New directions for management accounting

Using a general systems rationale, this paper develops a theoretical structure for approaching the problem of management accounting. The management control problem is explicated in terms of maintaining a relationship between the enterprise's structure and its environment. An enterprise's structure is composed of three elements (and their inter-relations): a decision and control subsystem; a financial funds subsystem and an operating (physical transforms) subsystem. Portrayed in these terms, the problem of management accounting is shown to require a methodology which is able to take cognizance of economic, sociological, psychological and other aspects of the enterprise system. The model described here provides a general intellectual frame of reference for ordering the problem.     

"This area has been declared a prostitution free zone": discursive formations of space, the state, and trans "sex worker" bodies

The mayorally instituted and police-enforced Prostitution Free Zones in Washington, DC, serve as a tool of nation-state disciplinarity, wherein many transgender women of color, viewed as ideologically suspect, are profiled as "sex workers," facing police harassment and arrest. This article explores here how this process is not merely about sex work but rather about discourses that are evoked in the displacement of the always-already displaced-racial, sexed, and gendered "others" through interviews with activists and trans community members, as well as District of Columbia government publications.     

Diversification and Performance in Developed and Emerging Market Contexts: A Review of the Literature*

The link between diversification and performance has become an important topic for research in diverse fields such as strategic management, industrial organization and financial management. However, a synthesis of the research done in developed and emerging markets is missing. This paper attempts such a synthesis by comparing and contrasting the past cumulative empirical research evidence on the relationship between diversification and firm performance in the context of developed economies to the more recent work in the emerging economies. The empirical literature has been divided into three broad perspectives, and the paper highlights the considerable diversity in its findings in developed and emerging markets across each of these perspectives. Based on this study, it is proposed that related diversification is preferable in developed economies and should be based on specific resources, whereas unrelated diversification is appropriate in emerging economies and should be based on generic resources. Although agency problems exist in both contexts, it is argued that the type of problem differs in developed and emerging markets. The paper concludes by identifying three directions for future research. First, the relationship between diversification and performance should be examined across each industry separately and not in aggregate. Secondly, future research needs to examine the organizational mechanisms required to make diversification successful. Finally, the relationship needs to be examined under unstable and dynamic situations such as the current global economic downturn.     

Bad News about Bad News: The Disclosure of Risks to Insurability in Research Consent Processes

Many people have difficulty in generating random numbers. This difficulty suggests that potentially fabricated numbers encountered in investigations of scientific misconduct be examined for nonrandom behavior. The present paper shows that even with a conscious effort to construct random digits, many subjects are unable to produce digits with a uniform distribution. For this study, subjects were directed to try to produce random digits in three places in order to fabricate a series of “pick 3”; lottery numbers. Subjects were most successful at producing a random (uniform) distribution of digits for the leftmost place; however, success at one place was not associated with success at another. In addition, subjects did not select all digits with equal frequency. Of 8,280 digits chosen in this study, the order from most to least chosen was 1, 2, 3, 6, 4, 9, 7, 0, 8, 5. Finally, no strong correlations among subjects’ digit choices were found. The conscious effort by these subjects to produce random digits stands in contrast with the usual case of data fabrication in which the fabricator must devote a conscious effort to choose leftmost digits so the number has the magnitude desired and pays little or no attention to the fact that the rightmost digits should be random. The results of the present paper indicate that even if a data‐fabricator were aware that error digits would be examined for uniformity, success in constructing uniform error distributions is not guaranteed. The difficulty that people have in creating random error digits supports the utility of examining such digits in investigations of scientific misconduct.