Common Learning with Intertemporal Dependence

Consider two agents who learn the value of an unknown parameter by observing a sequence of private signals. Will the agents commonly learn the value of the parameter, i.e., will the true value of the parameter become approximate common-knowledge? If the signals are independent and identically distributed across time (but not necessarily across agents), the answer is yes (Cripps, Ely, Mailath, and Samuelson, 2008). This paper explores the implications of allowing the signals to be dependent over time. We present a counterexample showing that even extremely simple time dependence can preclude common learning, and present sufficient conditions for common learning.Common learning, common belief, private signals, private beliefs

A general theory of intertemporal decision-making and the perception of time

Animals and humans make decisions based on their expected outcomes. Since relevant outcomes are often delayed, perceiving delays and choosing between earlier versus later rewards (intertemporal decision-making) is an essential component of animal behavior. The myriad observations made in experiments studying intertemporal decision-making and time perception have not yet been rationalized within a single theory. Here we present a theory-Training--Integrated Maximized Estimation of Reinforcement Rate (TIMERR)--that explains a wide variety of behavioral observations made in intertemporal decision-making and the perception of time. Our theory postulates that animals make intertemporal choices to optimize expected reward rates over a limited temporal window; this window includes a past integration interval (over which experienced reward rate is estimated) and the expected delay to future reward. Using this theory, we derive a mathematical expression for the subjective representation of time. A unique contribution of our work is in finding that the past integration interval directly determines the steepness of temporal discounting and the nonlinearity of time perception. In so doing, our theory provides a single framework to understand both intertemporal decision-making and time perception.Comment: 37 pages, 4 main figures, 3 supplementary figure

Universal banks and relationships with firms : [Version Mai 2003]

Some of the most widely expressed myths about the German financial system are concerned with the close ties and intensive interaction between banks and firms, often described as Hausbank relationships. Links between banks and firms include direct shareholdings, board representation, and proxy voting and are particularly significant for corporate governance. Allegedly, these relationships promote investment and improve the performance of firms. Furthermore, German universal banks are believed to play a special role as large and informed monitoring investors (shareholders). However, for the very same reasons, German universal banks are frequently accused of abusing their influence on firms by exploiting rents and sustaining the entrenchment of firms against efficient transfers of firm control. In this paper, we review recent empirical evidence regarding the special role of banks for the corporate governance of German firms. We differentiate between large exchangelisted firms and small and medium sized companies throughout. With respect to the role of banks as monitoring investors, the evidence does not unanimously support a special role of banks for large firms. Only one study finds that banks´ control of management goes beyond what nonbank shareholders achieve. Proxyvoting rights apparently do not provide a significant means for banks to exert management control. Most of the recent evidence regarding small firms suggests that a Hausbank relationship can indeed be beneficial. Hausbanks are more willing to sustain financing when borrower quality deteriorates, and they invest more often than arm´s length banks in workouts if borrowers face financial distress

Modeling the Psychology of Consumer and Firm Behavior with Behavioral Economics

Marketing is an applied science that tries to explain and influence how firms and consumers actually behave in markets. Marketing models are usually applications of economic theories. These theories are general and produce precise predictions, but they rely on strong assumptions of rationality of consumers and firms. Theories based on rationality limits could prove similarly general and precise, while grounding theories in psychological plausibility and explaining facts which are puzzles for the standard approach. Behavioral economics explores the implications of limits of rationality. The goal is to make economic theories more plausible while maintaining formal power and accurate prediction of field data. This review focuses selectively on six types of models used in behavioral economics that can be applied to marketing. Three of the models generalize consumer preference to allow (1) sensitivity to reference points (and loss-aversion); (2) social preferences toward outcomes of others; and (3) preference for instant gratification (quasi-hyperbolic discounting). The three models are applied to industrial channel bargaining, salesforce compensation, and pricing of virtuous goods such as gym memberships. The other three models generalize the concept of gametheoretic equilibrium, allowing decision makers to make mistakes (quantal response equilibrium), encounter limits on the depth of strategic thinking (cognitive hierarchy), and equilibrate by learning from feedback (self-tuning EWA). These are applied to marketing strategy problems involving differentiated products, competitive entry into large and small markets, and low-price guarantees. The main goal of this selected review is to encourage marketing researchers of all kinds to apply these tools to marketing. Understanding the models and applying them is a technical challenge for marketing modelers, which also requires thoughtful input from psychologists studying details of consumer behavior. As a result, models like these could create a common language for modelers who prize formality and psychologists who prize realism

Learning Under Ambiguity

This paper considers learning when the distinction between risk and ambiguity (Knightian uncertainty) matters. Working within the framework of recursive multiple-priors utility, the paper formulates a counterpart of the Bayesian model of learning about an uncertain parameter from conditionally i.i.d. signals. Ambiguous signals capture responses to information that cannot be captured by noisy signals. They induce nonmonotonic changes in agent confidence and prevent ambiguity from vanishing in the limit. In a dynamic portfolio choice model, learning about ambiguous returns leads to endogenous stock market participation costs that depend on past market performance. Hedging of ambiguity provides a new reason why the investment horizon matters for portfolio choice.ambiguity, learning, noisy signals, ambiguous signals, quality information, portfolio choice, portfolio diversification, Ellsberg Paradox

The Role of Experienced Regret on Intertemporal Choice: An Experiment

Theoretical and empirical body of research have exposed the powerful role of experiencing regret in guiding choice behavior. In this paper, we examined the impact of experienced regret and rejoicing induced by feedback provided on a risk decision prior to a two-period intertemporal choice. To our knowledge, this is the first attempt to bring together experienced regret and choice over time. We used the two-component discounted utility model approach as a framework. We applied previous research findings on the effect of experienced regret on utility, and we performed an experiment to test whether experienced regret and rejoicing have an impact on the discount factor. We found that both experienced regret and rejoicing have an impact on the way people discount future: when regret is experienced the discount factor decreases, whereas when rejoicing is experienced the discount factor increases.intertemporal choice, regret theory

High temporal discounters overvalue immediate rewards rather than undervalue future rewards : an event-related brain potential study

Impulsivity is characterized in part by heightened sensitivity to immediate relative to future rewards. Although previous research has suggested that "high discounters" in intertemporal choice tasks tend to prefer immediate over future rewards because they devalue the latter, it remains possible that they instead overvalue immediate rewards. To investigate this question, we recorded the reward positivity, a component of the event-related brain potential (ERP) associated with reward processing, with participants engaged in a task in which they received both immediate and future rewards and nonrewards. The participants also completed a temporal discounting task without ERP recording. We found that immediate but not future rewards elicited the reward positivity. High discounters also produced larger reward positivities to immediate rewards than did low discounters, indicating that high discounters relatively overvalued immediate rewards. These findings suggest that high discounters may be more motivated than low discounters to work for monetary rewards, irrespective of the time of arrival of the incentives

Beliefs, Doubts and Learning: Valuing Economic Risk

This paper explores two perspectives on the rational expectations hypothesis. One perspective is that of economic agents in such a model, who form inferences about the future using probabilities implied by the model. The other is that of an econometrician who makes inferences about the probability model that economic agents are presumed to use. Typically it is assumed that economic agents know more than the econometrician, and econometric ambiguity is often withheld from the economic agents. To understand better both of these perspectives and the relation between them, I appeal to statistical decision theory to characterize when learning or discriminating among competing probability models is challenging. I also use choice theory under uncertainty to explore the ramifications of model uncertainty and learning in environments in which historical data may be insufficient to yield precise probability statements. I use both tools to reassess the macroeconomic underpinnings of asset pricing models. I illustrate how statistical ambiguity can alter the risk-return tradeoff familiar from asset pricing; and I show that when real time learning is included risk premia are larger when macroeconomic growth is lower than average.

Resource Boom, Productivity Growth and Real Exchange Rate Dynamics - A dynamic general equilibrium analysis of South Africa.

We study the impact of a natural resource boom on structural change and real exchange rate dynamics, taking into account the indirect effect via relative sectoral productivity changes. Our contribution relative to the Dutch disease literature is threefold. First, the productivity specification is extended from simple learning by doing to include trade barriers and technology gap dynamics, consistent with the modern understanding of productivity growth. Second, we offer a dynamic general equilibrium model with imperfect substitution between domestic and foreign goods. Third, the model is applied to South Africa and analyzes the macroeconomic impact of the gold price increase in the 1970s. Political pressure for rapid domestic spending after a surge in resource rents tends to generate myopic government behavior with unsustainable high consumption spending. Such fiscal response to higher resource income is captured by the model specification. Numerical simulations show how the resource boom can help explain the structural change and real exchange rate path observed in South Africa. Due to productivity effects the initial real appreciation is followed by gradual depreciation of the real exchange rate.gold price boom;Dutch disease;trade barriers;fiscal response;deindustrialization