Minimizing the Probability of Ruin When Consumption is Ratcheted

Abstract

We assume that an agent’s rate of consumption is ratcheted; that is, it forms a nondecreasing process. We assume that the agent invests in a financial market with one riskless and one risky asset, with the latter’s price following geometric Brownian motion as in the Black-Scholes model. Given the rate of consumption, we act as financial advisers and find the optimal investment strategy for the agent who wishes to minimize his probability of ruin. To solve this minimization problem, we use techniques from stochastic optimal control.     

Controlling Investment Decisions: Depreciation- and Capital Charges

This paper examines a multiperiod principal-agent model in which a divisional manager has superior information regarding the profitability of an investment project available to his division. The manager also contributes to the periodic operating cash flows of his division through personally costly effort. We demonstrate that it is optimal for the principal to delegate the investment decision and to base the manager's compensation on the residual income performance measure. Our analysis points to a class of depreciation rules and to a particular capital charge rate which together ensure that a profitable (unprofitable) project makes a positive (negative) contribution to residual income in every period. As a consequence, the compensation parameters for each period can be chosen freely so as to address the moral hazard problems without impacting the manager's investment incentives.     

Robust portfolio choice with stochastic interest rates

We determine the optimal investment strategy for an ambiguity-averse investor in a setting with stochastic interest rates. The investor has access to stocks, bonds, and a bank account and he is ambiguous about the expected rate of return of both bonds and stocks. The investor can have different levels of ambiguity aversion about the two types of risky assets. We find that it is more important to take model uncertainty about the stock dynamics than model uncertainty about the bond dynamics into account. Furthermore, the investor’s ambiguity increases his hedging demand. Consequently, the bond/stock ratio increases with his ambiguity and implies less extreme positions in the bank account. Altogether, our model yields portfolio allocations which are more in line with what is implementable in practice. Finally, we demonstrate that neglecting model uncertainty implies significant losses for the investor.     

上市公司可持续发展问题研究

本文认为，上市公司经营的稳定性、业绩的成长性和发展的持续性界定为可持续发展。本文通过对123家可持续发展能力不足和11家具有较强可持续发展能力的两类上市公司研究发现，完善的公司治理则是可持续发展的基础，大股东掏空上市公司、违规担保和委托理财、盲目进行不相关多元化投资、欺诈上市是导致上市公司难以持续经营的主要原因，而专注主业、善于资本经营，品牌、创新和管理优势是实现上市公司可持续发展的关键因素.     

On a property of the sequential t-test

Abstract

1. Introduction. In one of his papers [1], and later in his book on sequential analysis [2], Wald introduced a general method for constructing sequential tests of composite hypotheses and applied the method to construct a sequential t-test. Since Wald devoted a considerable amount of space and mathematics on his t-test, it has been taken for granted that he proved certain optimum properties of the test. It is the purpose of this note to show that the test cannot possess one of the properties thought to hold for it.     

Back where we belong

If you were the CEO of Pitney Bowes, the postage meter maker, how would you envision the future of the business? The company has an undeniable core competence in the solutions it provides to high-volume postal service users. But with snail mail on the decline, some would say that core has about as much future as the buggy whip. In this article, Pitney Bowes chairman and CEO Michael Critelli gives us a glimpse of how he leads his company's strategy development--and how that development has supported a counterintuitive return to the company's core after decades of diversification. He and others in the company begin the process by tapping into deeply knowledgeable people and organizations to understand key trends in the business and the rate at which change is occurring. Then, it's a question of the firm reshaping the environment in which it does business, whether through R&D investments or work with regulators and policy makers who influence market forces; this is especially important in emerging markets. Focusing on a core business area enables a company to find adjacent high-margin opportunities and to offer comprehensive solutions to customers. What stands out most sharply in this account, however, is the importance of having a strategist's mind-set. Whether Critelli is reading the day's news, visiting a key account, or spending an hour with his own people working in the context of a customer mail room, he is constantly extrapolating possible long-term competitive implications from the immediate facts. Often inspired by strategic thinkers, Critelli believes that the greatest thing he can do for his organization is to shift the terms of the debate. "Rarely am I credited with sterling words or bold, symbolic actions", he writes. "Instead, I help people to see the business we are in differently and to reach a shared vision as to where we want to end up. And, little by little, things move in the right direction".     

The center-cut solution

Timothy Firnstahl owns five successful restaurants in Seattle, but he recently came very close to owning none. In the early 1990s, he found himself, like so many restauranteurs, facing rising costs, inefficient management, and a recession. Confronting financial annihilation, Firnstahl had to act quickly: since he had no peripherals to trim, he cut off the head of his company. Remarkably, it worked. Firnstahl's problem was his new and innovative restaurant, Sharps Fresh Roasting. The heart of the Sharps concept was a unique long-roasting technique that made lean, inexpensive meats taste as juicy and delicious as fattier, expensive cuts. The process also lent itself to faster service and lower labor costs. But it wasn't working. Sharps wasn't breaking even, and his other restaurants couldn't make up the difference. He needed a solution fast. Firnstahl got his answer from Mikhail Gorbachev: slash the centralized command and liberate the company. In doing so, he would also transfer virtually all power and responsibility to his line managers. And after five months of intensive study and planning, he accomplished what he set out to do. He fired most of his corporate staff, empowered his restaurant managers with "100% Power and Responsibility," and, finally, undertook a massive promotion campaign. A year later, Sharps Fresh Roasting is the gold mine Firnstahl always believed it could be. He's done away with bureaucracy and turned business around in a down market. All this because his managers are managing themselves.     

徐曙光 董事长专业户的成功法则

他曾连续成功创业,并跨越不同的国家、涉足不同的领域。他正是董事长专业户徐曙光。     

The best advice I ever got

A young manager faces an impasse in his career. He goes to see his mentor at the company, who closes the office door, offers the young man a chair, recounts a few war stories, and serves up a few specific pointers about the problem at hand. Then, just as the young manager is getting up to leave, the elder executive adds one small kernel of avuncular wisdom--which the junior manager carries with him through the rest of his career. Such is the nature of business advice. Or is it? The six essays in this article suggest otherwise. Few of the leaders who tell their stories here got their best advice in stereotypical form, as an aphorism or a platitude. For Ogilvy & Mather chief Shelly Lazarus, profound insight came from a remark aimed at relieving the tension of the moment. For Novartis CEO Daniel Vasella, it was an apt comment, made on a snowy day, back when he was a medical resident. For publishing magnate Earl Graves and Starwood Hotels' Barry Sternlicht, advice they received about trust from early bosses took on ever deeper and more practical meaning as their careers progressed. For Goldman Sachs chairman Henry Paulson, Jr., it was as much his father's example as it was a specific piece of advice his father handed down to him. And fashion designer Liz Lange rejects the very notion that there's inherent wisdom in accepting other people's advice. As these stories demonstrate, people find wisdom when they least expect to, and they never really know what piece of advice will transcend the moment, profoundly affecting how they later make decisions, evaluate people, and examine--and reexamine--their own actions.     

Knowledge,risk and Beck: Misconceptions of expertise and risk

Ulrich Beck's work is beginning to alter how risk is understood. This paper maps out the core of Beck's argument and provides a critique of his analysis. In particular it argues that this emerging concept of risk is flawed because it is not rooted in an ontological view of knowledge and, hence, it misunderstands the relationship between experts, expert knowledge and lay knowledge. Because of his downgrading of ontology, Beck under-theorizes the politics of expertise and the sociality of knowledge hence we should be cautious in our use of his analysis of risk and organization in late modernity.

It has been said civilization is a race between education and catastrophe. With Katrina, we have had the catastrophe, and we are racing inexorably toward the next. Americans want to know; what have we learned?

(US Select Bipartisan Committee, 2006; ix)

     

利益相关者会计行为的分析

本文把利益相关者纳入到会计行为分析的框架中进行分析,认为每一类利益相关者对待会计信息的态度都具有两面性。一方面,每一类利益相关者的经济利益都和会计信息有着密切的联系,自利的本性使他们都有通过操纵会计信息而谋取私利的动机,在条件具备时,这种动机就会转化为实际的操纵会计信息的行为;另一方面,各类利益相关者的经济利益之间存在着相互制约、此消彼长的关系,因此,可能遭受损失的利益相关者就会对其他利益相关者操纵会计信息的行为进行监督。这种两面性说明,每一类利益相关者的利益都可能受到来自其他类利益相关者操纵会计信息的威胁,因此,必须建立利益相关者相互之间进行会计监督的体系。     

The effects of dividend yield and dividend policy on common stock prices and returns

This paper suggests that it is not possible to demonstrate, using the best available empirical methods, that the expected returns on high yield common stocks differ from the expected returns on low yield common stocks either before or after taxes. A taxable investor who concentrates his portfolio in low yield securities cannot tell from the data whether he is increasing or decreasing his expected after-tax return by so doing. A tax exempt investor who concentrates his portfolio in high yield securities cannot tell from the data whether he is increasing or decreasing his expected return. We argue that the best method for testing the effects of dividend policy on stock prices is to test the effects of dividend yield on stock returns. Thus the fact that we cannot tell, using the best available methods, what effects dividend yield has on stock returns implies that we cannot tell what effect, if any, a change in dividend policy will have on a corporation's stock price.     

Retirement income adequacy: good news or bad?

Estimating replacement rate targets, and using them to assess the current state of retirement savings adequacy, has been the focus of much attention and analysis. Building on his earlier work published in Benefits Quarterly, the author conceptually defines retirement income adequacy, estimates replacement rate targets and reviews research on the current state of baby boomers' retirement savings. He concludes that, despite existing data limitations, researchers have made considerable strides in recent years in thinking about saving for retirement and the adequacy of workers' preparation for it. These advances suggest that singular rules of thumb for replacement rates are naive and that estimates should take into account the unforeseen risks that individuals face.     

Strategic intensity: a conversation with world chess champion Garry Kasparov

It's hard to find a better exemplar for competition than chess. The image of two brilliant minds locked in a battle of skill and will-in which chance plays little or no apparent role-is compelling. Even people who have scant knowledge of the game instinctively recognize that chess is unusual in terms of its intellectual complexity and the strategic demands it places on players. Can strategists learn anything from chess players about what it takes to win? To find out, H BR senior editor Diane L. Coutu talked with Garry Kasparov, the world's number one player since 1984. Kasparov believes that success in both chess and business is very much a question of psychological advantage; the complexity of the game demands that players rely heavily on their instincts and on gamesmanship. In this wide-ranging interview, Kasparov explores the power of chess as a model for business competition; the balance that chess players strike between intuition and analysis; the significance of his loss to IBM's chess-playing computer, Deep Blue; and how his legendary rivalry with Anatoly Karpov, Kasparov's predecessor as World Chess Champion, affected his own success. Kasparov also shares his solution to what he calls the champion's dilemma, a question for all world masters, whether they are in business, sports, or chess: Where does a virtuoso go after he has accomplished everything he's ever wanted to, even beyond his wildest imagination? If you are lucky, says Kasparov, your enemies will push you to be passionate about staying at the top.     

毕凌峰“另类”法则

作为一家2007年成立的新兴基金,行健资本(Stepstone)不同于传统的FOF基金"一揽子"的投资策略,而是针对不同的大型基金,根据该基金的特点、需求、定位等要求提出针对其一家公司的投资组合策略,这在私募股权市场上无疑是一种新的尝试。这种新的尝试很快通过了市场的检验,在行健资本成立短短的4年时间,创造了管理330多亿美元的神话。而之所以取得如此的成绩,都在于其创始人在基金成立之初对于行健资本的规划。     

Bob's meltdown

Annette Innella is just coming into the lunchroom at Concord Machines when Bob Dunn starts screaming at her. After throwing his lunch tray against the wall, he stomps out, leaving Annette stunned. Naturally, Annette, the new senior VP for knowledge management, is beside herself. She knows her proposal to establish a cross-functional knowledge management committee is progressive thinking for this oldline manufacturer, but Bob's reaction is totally over the line. If Bob stays, she goes--that's all there is to it. Bob is contrite, but he's under a lot of pressure. The general manager of the Services Group, he's just returned from a two-week trip around the globe to gear up his troops to beat revenue targets again, despite shrinking budgets and hiring freezes. And what does he see when he gets back? An e-mail from Annette requesting that two of his best people devote half their time to what he calls her "idiotic" Knowledge Protocols Group. He's carrying the company on his back, and she's throwing this nonsense at him. Graphics specialist Paula Chancellor is surprised. Sure, Bob's gruff, but his staff loves him, and he's the only one of the big shots who ever talks to her. But HR director Nathan Singer is incensed; Bob's never been a team player, Singer complains, and it's time he learned a lesson. CEO Jay Nguyen is in a bind. Bob is his top manager; he brings in all the money. And even though future revenues are going to have to come from somewhere else, Jay is not totally behind Annette's initiative in the current business climate. He can't afford to lose Bob. But if he reins in Annette, it will look like he's condoning Bob's outburst. What should he do? Four commentators offer advice in this fictional case study.     

Managerial Disclosures and Shareholder Litigation

This paper explores the link between shareholder lawsuits brought under Rule 10b-5 of the Securities Exchange Act of 1934 and managerial disclosures of prospective information. When the manager's information is such that there is no affirmative duty to disclose under Rule 10b-5, previous research has shown that the manager will withhold his information if it is sufficiently unfavorable and will disclose it otherwise. When the manager's information is such that there exists an affirmative duty to disclose under Rule 10b-5, it is shown here that the manager will release either good news or news that is sufficiently bad. Further, the good news disclosures are expected to be more precise than those that reflect unfavorable information. It is also demonstrated that the probability of a disclosure will increase with both the precision of the manager's information and the variability of his firm's earnings.     

New Leadership at the Federal Reserve*

As Chairman of the Federal Reserve for the past 18 years, Alan Greenspan deserves praise for his stewardship of monetary policy. He has guided the Fed and monetary policy in a way that has led to low and stable inflation. But if Greenspan's record clearly deserves praise, he could have done more to move monetary policy into the 21st century and prepare the institution for the future. Greenspan has relied heavily on his personal judgment and has argued repeatedly that the Fed must have extensive flexibility to respond to the economic environment. But if Greenspan's judgment, skill, and luck have served him and the country well, it is dangerous to rely so heavily on the judgment of a single individual. When he departed, he took with him his skill and judgment, as well as his credibility and his personal commitment to low inflation. The Fed he leaves behind has no explicit institutional commitment to long‐run price stability. This article argues that by operating with a set of rules and guidelines, or at a minimum clearly stated institutional objectives, the Fed would eliminate much of the second guessing about what it is doing and why, and the associated volatility in markets. More generally, the benefits of more explicit guidelines for monetary policy include:

• ? Increasing public understanding of monetary policy, including what it can and cannot do.
• ? Increasing transparency and accountability. Most organizations have clear goals and we hold their leaders accountable. The Fed is different. The Fed seems to be held accountable for all things economic and thus it is truly accountable for nothing. It never has to explain its actions and what went right or wrong.
• ? Establishing a clear focus for the Fed regarding its goals and objectives.
• ? Creating increased confidence that sound monetary policy will be followed in the future.

     

PAPER PROPHETS AND THE CONTINUING CASE FOR THINKING DIFFERENTLY ABOUT ACCOUNTING RESEARCH

This review of Tony Tinker’s Autocritique presented at the First International Accounting Seminar, Department of Finance and Accounting, Glasgow Caledonian University, is not a critique of what Tinker thinks of his own book. He should know best about what he wrote or wanted to write. It also does not assess the validity of his interpretation of the works of Marx or Hegel. What it does is to reflect further on an important issue underlying much of Tinker’s presentation—namely, the concern with research methodology. The review welcomes Tinker’s desires for change in approaches to accounting case studies but suggests that the underlying problems are more complex than Tinker suggests and demands a broader scale of response than that highlighted in his presentation.     

Buyer Brokerage: Incentive and Efficiency Implications

This article examines the incentive and efficiency implications of buyer brokerage. We show that it is possible to perfectly align the interests of the seller with those of his agent and the interests of the buyer with those of his agent. Furthermore, effort levels can be efficient. This result is a departure from earlier conclusions in the literature that the agent's effort level can neither be perfectly aligned with the principal's interests nor be efficient. The departure is primarily due to the feature of our model that it recognizes the costs as well as the benefits of an agent's effort to her principal, and vice versa. Finally, we discuss the implications of buyer brokerage for the future of MLS services.