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using or others could use this book in courses, seminars and workshops that deal<br />

with useful theory for real investment problems.<br />

The 1975 edition was used by many students and faculty and helped evolve<br />

the then young field of optimization under uncertainty models of theory and<br />

economic results. Part I on mathematical tools focuses on expected utility<br />

theory, convexity and the Kuhn-Tucker conditions and dynamic programming.<br />

Each of these areas was well developed in 1975; however, progress has<br />

continued in all three areas. Fishburn's comprehensive theory of subjective<br />

probabilities and expected utilities still provides an excellent introduction to<br />

utility theory. A notable subsequent area of expected utility theory is the prospect<br />

theory of Kahneman and Tversky (1979, 1982), work for which Kahneman<br />

won the Nobel prize in economics in 2003. They devised a utility theory to<br />

analyze the notion that individuals typically fear loss greater than they enjoy<br />

gains, that there is framing of decisions with different decisions made in identical<br />

situations except the way it is presented and that low probability events are<br />

typically overestimated and high probability events underestimated. These ideas<br />

are used in many places in mainstream academic finance, financial engineering,<br />

fund management and other areas, and some date from much earlier. For<br />

example, articles on the favorite-longshot bias, related to the third Kahneman<br />

and Tversky area, were originally published in 1949 and 1956. They are<br />

reprinted in the racetrack efficiency studies volume of Hausch, Lo and Ziemba<br />

(1994). The bias there is that high probability events have somewhat higher<br />

expected average returns and low probability events are greatly overestimated.<br />

The advent of betting exchanges such as Betfair and rebate betting has flattened<br />

this bias somewhat but it is still strong; see Hausch and Ziemba (2007). Hausch,<br />

Ziemba and Rubinstein (1981) introduced the notion that biases might be<br />

exploitable in racetrack betting if you use probabilities from simple markets in<br />

complex markets. That paper and Hausch and Ziemba (1985) introduced Kelly<br />

log utility betting into racetrack betting models. This area has grown immensely<br />

as well and a recent survey with updated results is in Hausch and Ziemba<br />

(2007). Tompkins, Ziemba and Hodges (2003) show that biases are similar in<br />

the S&P500 and the FTSEIOO stock indices as well. The two papers by<br />

Mangasarian on pseudo-convex and composite functions remain classics to this<br />

day and are constantly used in portfolio theory by those who know about them.<br />

Dynamic programming remains an active field and it is frequently used in<br />

economic and financial studies. My (Ziemba) paper is still a useful introduction<br />

to the theory and concepts. See Bertsekas (2005) for a through treatment, in<br />

discrete and continuous time. Campbell and Viceira (2002) is a recent example<br />

XIV PREFACE AND BRIEF NOTES TO THE 2006 EDITION

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