Comments’ Extraction by User ID,Keywords, and Anchor Texts from the Thread of a Bulletin Board System

Bulletin Board Systems (BBSs) on the Web are used by many users posting comments on threads. Each thread carries a subject of discussion. Most users post comments related to a subject. However, unrelated comments are also posted. The unrelated comments distract users and diminish their understanding of the entire story of a thread. Comments unrelated to a subject have to be filtered automatically. This paper proposes a method that extracts comments related to a thread subject from a thread of BBS. The method extracts two types of comments: comments related to a thread subject (main comments), and comments related to main comments (sub-comments). The main comments are extracted by a user ID and keywords in the comments. The sub-comments are extracted by explicit and implicit anchor texts in the comments. We experimented with the proposed method and verified that comments extracted by the proposed method support participants in understanding the entire story of a thread.     

Stability of the cooperative equilibrium in N-person prisoners' dilemma with sequential moves

Summary. Nishihara [3] showed that N-person prisoners' dilemma has a cooperative Nash equilibrium, if the players decide their actions sequentially in the order determined by Nature under a certain information structure, and if each player's payoffs satisfy a certain inequality. This paper examines the stability of this cooperative equilibrium against two matters: players' slight mistakes and deviations by coalitions. The main results are as follows: (i) if the inequality on each player's payoffs strictly holds, then the cooperative equilibrium is a strictly proper equilibrium; (ii) if N≤3, and if full cooperation is Pareto efficient in N-person prisoners' dilemma, then the cooperative equilibrium is a strong Nash equilibrium; (iii) the cooperative equilibrium is in general a coalition-proof Nash equilibrium. Received: June 23, 1997; revised version: December 2, 1997     

The Role of Ethics and Social Responsibility in Organizational Success: A Spanish Perspective

Ethics has assumed a dominant position in the current economic debate, and this study focuses on ethics as a legitimate underpinning to good business decision making. Using a self-response survey of marketing managers in Spain, the current theory on ethical decision making is extended. Results support the mediating influence of the PRESOR construct (an individual’s perception of the importance of ethics and social responsibility for the effectiveness of the organization) on relativistic and idealistic moral thinking when one is considering the moral intensity of a situation. In addition, the study found support for the relationship between relativism (negative), idealism (positive), corporate ethical values, and job satisfaction, thereby providing additional support for the prior theory. Finally, a thorough review of the extant literature and suggestions for future ethics research in the marketing field are included.     

Agency cost of debt overhang with optimal investment timing and size

The concept of debt overhang (that is, an equity‐maximizing levered firm will under‐invest relative to a firm‐value‐maximizing firm) is well established in the literature. A number of papers have demonstrated it as delayed investment (when investment size is specified) or smaller investment (when investment time is specified). However, there is no work on the underinvestment effect when the firm chooses both size and timing of investment, as it usually does in real life. This is what our paper focuses on. When the firm has the flexibility to choose both size and time, the effect is complicated by the fact that delayed investment results in larger investment, which suggests that the underinvestment problem might be mitigated. We find, however, that the effect depends on how underinvestment is measured. When measured by the expected present value of investment, flexibility can mitigate or exacerbate the underinvestment problem, depending on the cost of installing capacity. But when measured by the agency cost, flexibility always exacerbates the underinvestment problem. It is shown numerically that, at the optimal leverage ratio, the agency cost with plausible parameter values can be economically significant. Thus, with the flexibility of choosing both time and size of investment, the debt overhang problem can be of significant practical relevance in corporate investment decisions.     

A resolution of N-person prisoners' dilemma

Summary. The purpose of this paper is to show that cooperation is possible in N-person prisoners' dilemma if players have incomplete information on the order of their moves. We consider a modified version of N-person prisoners' dilemma in which players sequentially move in the order determined by Nature, and during the play they get some information about others. We provide an information partition and a condition of payoffs for which cooperation is attained in an equilibrium. Further, for the case that full cooperation is not attained, we examine the largest partial cooperation which is achieved in an equilibrium. Received: March 5, 1995; revised version August 11, 1996     

The Effects of Reversible Investment on Capital Structure and Credit Risks

We propose a structural model with an optimal switching of diffusion regimes that integrates a wide range of investment reversibility. The default boundary and switching thresholds are endogenously determined, and they enable us to comprehend the interrelated problems of the investment decision, capital structure, and credit risks. We examine not only the under/overinvestment but also the under/overdisinvestment. The leverage ratio decreases when the firm has an option to invest in a reversible project, which can alleviate the capital structure puzzle. Furthermore, the model significantly reduces the wide dispersion of yield spreads depending on the credit grade of bonds.     

Preemption,leverage, and financing constraints

This paper investigates the interactions between preemptive competition and leverage in a duopoly market. We investigate both a case in which the firms have optimal financial structures, and a case in which financing constraints require firms to finance their investments by debt. Our findings are that the second mover always leaves the duopoly market before the leader, although the leader may exit before the follower's entry. The leverage effects of debt financing can increase the value of a firm and accelerate investment, even in the presence of preemptive competition. Notably, financing constraints can delay preemptive investment and improve firm values in preemptive equilibrium. Indeed, the leader's high leverage due to financing constraints can lower the first-mover advantage and weaken preemptive competition. Especially with strong first-mover advantage, the financing constraint effects can dominate the leverage effects. These findings are almost consistent with the empirical evidence, which shows that high leverage leads to competitive disadvantage and mitigates product market competition.     

OPERATING LEVERAGE AND UNDERINVESTMENT

Using a contingent claims model, we examine the impacts of both operating leverage and financial leverage on a firm's investment decisions in the context of capacity expansion. Our model shows that quasi‐fixed operating costs could significantly mitigate the underinvestment problem for debt‐financed firms. The existing debt induces equity holders to delay equity‐financed expansion because the expanded earnings base will also benefit the debt holders by lowering the bankruptcy risk. The operating costs decrease this type of wealth transfer from equity holders to debt holders by magnifying the bankruptcy risk of the existing debt upon investment. By applying the Cox proportional hazard model on a large sample of publicly traded U.S. firms over 1966–2016, we offer empirical support for the theoretical predictions. The results are robust to various measures of operating leverage.     

The effects of external financing costs on investment timing and sizing decisions

We develop a dynamic model in which a firm exercises an option to expand production on either a small or large scale with cash reserves and costly external funds. An intermediate level of cash reserves, which is insufficient for the large-scale investment but sufficient for the small-scale investment, provides an incentive for the firm to invest early in the small-scale project. These results fill the gap between two types of results: (i) empirical findings of a U-shaped relation between the investment volume and internal funds and (ii) empirical predictions of a U-shaped relation between the investment timing and internal funds. In addition, our results have real-world implications for investment in alternative projects.