به سوی سنتز نئو داروینی اقتصاد رفتاری و نئوکلاسیک
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|6795||2012||15 صفحه PDF||سفارش دهید||13256 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Journal of Economic Behavior & Organization, Available online 17 December 2012
There is a schism within economics between the neoclassical and behavioral schools. A primary cause of the behavioral ascent is the experimental evidence of deviations between actual behavior and the neoclassical prediction of behavior. While behavioral scholars have documented these “anomalies,” they have made little progress explaining the origin of such behavior. This paper proposes a biological and evolutionary foundation for the anomalies of behavioral economics by separating proximate and ultimate causation. Such a foundation may allow for a re-uniting of economics; a neo-Darwinian synthesis of neoclassical and behavioral economics.
Economics is divided into two competing schools based on divergent views of human nature. This paper argues that the two schools of economics can be re-connected by incorporating insights from the natural sciences. In particular, the concepts of proximate and ultimate causation may allow a synthesis of neoclassical and behavioral economics that reconciles and combines the competing perspectives. Behavioral economics has made significant advances in recent decades. An important source of these successes is the documentation of divergences between neoclassical predictions of human behavior and actual human behavior. Richard Thaler labels these divergences as “anomalies.” Neoclassical economists dismiss the behavioral anomalies as interesting quirks, laboratory artifacts, or small-stakes effects that can be ignored when working on important, real-world issues. Mainstream economic textbooks, economic teaching, and applied economics are still based primarily on the neoclassical assumptions. While much of economics maintains the status quo, behavioral economists, in turn, dismiss neoclassical economics as irrelevant, applied math. The two groups of economists do not communicate productively, and the schism is a major obstacle to improving economics. The field of economics is divided, and faces a crisis. Biologists have faced similar issues regarding the behavior of non-human animals. Animals exhibit sophisticated behaviors, but animals can also behave in ways that appear counterproductive. While economics has fragmented over the apparent contradiction of animals as both optimizers and bumblers, biology accommodates both in a single, unified view of behavior. Economists may benefit by incorporating the insights of natural scientists. Natural selection favors optimization, but the maximization is achieved by specific physical machinery that does not maximize in all settings (Mayr, 1961, Tinbergen, 1963 and Tinbergen, 1968). There is no schism in biology over maximization because natural scientists differentiate between the “ultimate” and “proximate” causes of behavior. The ultimate cause of a behavior is based in the evolutionary payoffs. The proximate cause of a behavior is based in specific machinery or “mechanism” that produces the behavior. Proximate cause can lead to behaviors that appear destructive or anomalous in the spirit of behavioral economics. An integrated view of behavior, that combines both ultimate and proximate causation, is richer and more productive than any single idea of causation. This paper is entitled “caveman economics” to highlight the difference between ancestral human environments and modern industrial or agricultural environments. Proximate mechanisms are more likely to lead to anomalous behavior in evolutionarily novel environments. The behaviors that puzzle economists occur primarily in two types of evolutionary novel environments: Laboratories for economic experiments, and modern industrialized societies. The caveman economic hypothesis is that behavioral anomalies are caused, in significant part, by an “evolutionary mismatch” between human proximate decision-making machinery and specific environments. The term evolutionary mismatch describes situations when traits are out of equilibrium with important aspects of the environment (Bowlby, 1969, Crespi, 2000, Lloyd et al., 2012, Tooby and Cosmides, 1989, Tooby and Cosmides, 1990 and Wilson, 1978). This paper focuses primarily on genetic mismatch; the notion that genes can be out of sync with the environment. If human preferences evolved by natural selection, and genetic mismatch is an important issue, then preferences were shaped in ancestral environments. Attempts to understand human economic preferences and behavior should, therefore, model the ancestral and not modern world. The caveman economics hypothesis is that a number of important puzzles in economics, including the anomalies of behavioral economics, may be resolved by understanding proximate and ultimate causation. Many puzzles in economics disappear when we consider the world of our ancestors and the implications for behavior. There are important caveats and uncertainties in the caveman economic approach. First, mismatch takes place for cultural evolution in addition to genetic evolution. This paper focuses on genetic mismatch, without explicit reference to cultural mismatch. However, it should be noted that culture is implicit. For example, evolutionary mismatch is frequently the product of cultural change. Genes and culture co-evolve so that cultures have been selecting genes as much as genes have been selecting cultures for a long time (Stoelhorst and Richerson, 2013 and Witt and Schwesinger, 2013). Second, humans have a unique ability to modify and control behavior; we are not lumbering robots, hard-wired to carry out genetic programs. Human genes build flexible behavior that is acutely sensitive to cultural nuances and social norms. This flexibility is greater than that found in other animals, and may even be qualitatively different. For example, our closest animal ancestors, the chimpanzees, have a harder time suppressing certain types of urges (Boysen et al., 1999) and capuchin monkeys appear to have an even harder time at delaying gratification than chimpanzees (Evans et al., 2012). Third, human brains may be uniquely able to adapt to evolutionary mismatch, thus mitigating the negative consequences. ‘Niche construction’ is a process where animals alter the environment. Some scholars argue that humans are so skilled at niche construction that the negative effects of the lag between genetic evolution and environmental change are mitigated (Laland and Brown, 2006). Furthermore, while this paper argues that the proximate/ultimate distinction will help economics, there is a new literature that de-emphasizes related ideas in the natural sciences (Bolhuis et al., 2011, Dean et al., 2012 and Laland et al., 2011). These three ideas highlight human cultural transmission and human behavioral flexibility, which may limit the benefit of incorporating genetic proximate and ultimate distinctions into economics. The benefit of focusing on genetic mismatch is that the clarity of the perspective may allow insights not available with a more nuanced perspective. The risk, of course, is that the simplification is too extreme, and leads to incorrect conclusions. These ideas are revisited in the discussion. In summary, economics is a field divided upon itself with the two main camps diverging. The specific goal of this paper is to demonstrate the utility of the distinction between proximate and ultimate causation for understanding behavioral anomalies. The longer term goal is to place economics into a consilient framework where human economic behavior is studied within the same framework as human non-economic behavior and non-human behavior. The remainder of this paper is structured as follows. In the next section, the schism between neoclassical and behavioral economics is elaborated in more detail. Next, the proximate/ultimate framework is introduced. Using this framework, biology is able to reconcile sophisticated behavior with other behaviors that appear anomalous. The subsequent section discusses two lines of research in economics using the proximate/ultimate framework. In these cases, the biological framework produces novel, testable hypotheses that are different from neoclassical and behavioral frameworks. The empirical data in the handful of studies that have been completed support the value of the biological framework to understanding economic behavior. The final discussion section looks forward to an economics based on an evolutionary and biological foundation.
نتیجه گیری انگلیسی
The debate between behavioral and neo-classical economics can be viewed, in significant part, as a failure to understand proximate and ultimate causation. Natural selection favors maximization of fitness, but the biological mechanisms that effect behavior use specific physiologic cues. Thus, these proximate causes can produce the anomalies of behavioral economics. Let us consider altruism, risk, and intertemporal discounting. Altruism and spite exist in laboratory situations when subjects earn less than they could either to help someone else (altruism) or to hurt someone else (spite). Outside the laboratory there are a number of situations that appear to fall into these categories, however, because of reputational effects it is much harder to document altruism and spite outside the laboratory. Caveman economics explains altruism and spite by a combination of mechanism and environment. The mental machinery that lubricates social exchange evolved in the ancestral environment. Based on archeological and anthropological evidence, it is likely that human ancestral environments involved fewer interactions with strangers, and much less privacy. Thus, behavioral anomalies that appear to be costly in the laboratory may have been produced by mechanisms that favored maximization in the ancestral environments. In short, altruism and spite in the laboratory are produced by the evolutionary novel feature of an interaction with no future and no reputation impact. Such settings, it is hypothesized, were sufficiently rare in the ancestral environment that the optimal decision rule, reified in human nature, is to act as if there is some substantial likelihood of repeat interaction or public disclosure of behavior (Burnham and Johnson, 2005, Fehr and Henrich, 2003, Johnson et al., 2003 and Trivers, 2004). Similar to this explanation for altruism, the caveman economic explanation for the behavioral anomalies regarding time preference is also a combination of mechanism and environment. Natural selection favors organisms that optimally trade-off behaviors between time periods. Squirrels, myriad bird species, and many other animals store food even though they earn negative interest rates in the form of retrieving less food than stored. Squirrels behave this way, presumably, because the marginal benefit of an acorn is high when the squirrel is hungry, high enough to justify the loss. Given the proficiency of non-human animals at delaying consumption, why do many behavioral experiments document too high a level of current consumption? The caveman economic hypothesis is that up until the invention of agriculture and ceramic pots around 10,000 years ago, it was much harder for humans to save. Without food preservation technology, it pays to eat everything, or give it away, as opposed to leaving the food to rot. Modern financial instruments, that allow people to earn positive real returns, are very recent inventions. In summary, the caveman economic explanation for so-called hyperbolic discounting is an ancestral environment with bad savings technology. In such a world, it pays to consume today (Daly and Wilson, 2005). Finally, what about loss aversion and other behavioral anomalies regarding risk? The caveman economic hypothesis is the same in this area as in altruism and discounting; the behavioral anomaly is produced in particular settings by mechanisms that arose in an ancestral setting. Are all the behavioral anomalies produced by proximate causes in particular environments? Natural scientists who study non-human behavior work with this assumption. Non-human behavior is studied through an integrated view of causation. There is no ‘behavioral’ school in biology that posits, for example, other-regarding preferences for non-human animals. Anomalous behavior that appears to be disadvantageous is the used by natural scientists as the beginning of a process of discovery. If it is true that biology reconciles non-human animal behavior into a unified framework, will the same approach work for humans? Not necessarily, and possibly because of the caveats regarding caveman economics in the introduction. Humans may be qualitatively different in transmitting ideas through culture, and in behavioral flexibility (Gould and Lewontin, 1979, Laland and Brown, 2006, Laland et al., 2011, Bolhuis et al., 2011 and Dean et al., 2012). Thus, the natural sciences approach may be more limited in explaining human behavior than non-human behavior. Most important economic behavior takes place outside the laboratory. Much of this paper has been devoted to investigating and explaining behavioral anomalies that are documented in laboratory experiments. Laboratory experiments play an important role because of the high-level of control. A person who makes an altruistic donation in the last stage of anonymous game cannot be repaid within the experiment. Analogous behaviors outside the laboratory, such as tipping a waiter on vacation, allow the possibility for reputation formation and are less clear evidence of deviations for neoclassical economics. While the laboratory is important for understanding, ‘real world’ behavior is more significant for most people. The caveman economic view based in proximate and ultimate causation may be central to many of the most important human issues (Burnham and Phelan, 2000). Many individuals in rich societies eat too much. This issue is easily reconciled with proximate mechanisms that arose in ancestral worlds with less food (Irons, 1998). Drug addiction is another problem where pleasure-seeking mechanisms that were good for our ancestors cause problems in modern settings. Moving more directly to financial decisions, people in some countries save very little. This can cause problems for individuals and societies. The novelty of savings instruments may lay at the foundation or our problems to use such financial instruments wisely. Caveman economics provides a path to a modern synthesis in economics. Both neoclassical and behavioral economics find support in the natural sciences view of human nature. Preferences arose via evolution by natural selection. In equilibrium, human behavior would conform more closely to the predictions of neoclassical economics. Because human genes are not in equilibrium with important aspects of our environment, however, maximization of preferences leads to the anomalies of behavioral economics.