Bayesian–Walrasian equilibria: beyond the rational expectations equilibrium

In general rational expectations equilibrium (REE), as introduced in Radner (Econometrica 47:655–678, 1978) in an Arrow–Debreu–McKenzie setting with uncertainty, does not exist. Moreover, it fails to be fully Pareto optimal and incentive compatible and is also not implementable as a perfect Bayesian equilibrium of an extensive form game (Glycopantis et al. in Econ Theory 26:765–791, 2005). The lack of all the above properties is mainly due to the fact that the agents are supposed to predict the equilibrium market clearing price (as agent’s expected maximized utility is conditioned on the information that equilibrium prices reveal), which leads inevitably to the presumption that agents know all the primitives in the economy, i.e., random initial endowments, random utility functions and private information sets. To get around this problematic equilibrium notion, we introduce a new concept called Bayesian–Walrasian equilibrium (BWE) which has Bayesian features. In particular, agents try to predict the market-clearing prices using Bayesian updating and evaluate their consumption in terms of Bayesian price estimates, which are different for each individual. In this framework agents maximize expected utility conditioned on their own private information about the state of nature, subject to a Bayesian estimated budget constraint. Market clearing is not an intrinsic part of the definition of BWE. However, both in the case of perfect foresight and in the case of symmetric information BWE leads to a statewise market clearing; it then becomes an ex post Walrasian equilibrium allocation. This new BWE exists under standard assumptions, in contrast to the REE. In particular, we show that our new BWE exists in the well-known example in Kreps (J Econ Theory 14:32–43, 1977), where REE fails to exist. This work was done in the Spring of 2005, when EJB was a visiting professor at the University of Illinois.     

On an optimal consumption problem for p-integrable consumption plans

A generalization is presented of the existence results for an optimal consumption problem of Aumann and Perles [4] and Cox and Huang [10]. In addition, we present a very general optimality principle. Received: July 14, 1999; revised version: September 9, 1999     

Launch Decisions and New Product Success: An Empirical Comparison of Consumer and Industrial Products

Many articles have investigated new product development success and failure. However, most of them have used the vantage point of characteristics of the product and development process in this research. In this article we extend this extensive stream of research, looking at factors affecting success; however, we look at the product in the context of the launch support program. We empirically answer the question of whether successful launch decisions differ for consumer and industrial products and identify how they differ. From data collected on over 1,000 product introductions, we first contrast consumer product launches with industrial product launches to identify key differences and similarities in launch decisions between market types. For consumer products, strategic launch decisions appear more defensive in nature, as they focus on defending current market positions. Industrial product strategic launch decisions seem more offensive, using technology and innovation to push the firm to operate outside their current realm of operations and move into new markets. The tactical marketing mix launch decisions (product, place, promotion and price) also differ markedly across the products launched for the two market types. Successful products were contrasted with failed products to identify those launch decisions that discriminate between both outcomes. Here the differences are more of degree rather than principle. Some launch decisions were associated with success for consumer and industrial products alike. Launch successes are more likely to be broader assortments of more innovative product improvements that are advertised with print advertising, independent of market. Other launch decisions uniquely related to success per product type, especially at the marketing mix level (pricing, distribution, and promotion in particular). The launch decisions most frequently made by firms are not well aligned with factors associated with higher success. Additionally, comparing the decisions associated with success to the recommendations for launches from the normative literature suggests that a number of conventional heuristics about how to launch products of each type will actually lead to failure rather than success.     

Dynamic portfolio optimization across hidden market regimes

Regime-based asset allocation has been shown to add value over rebalancing to static weights and, in particular, reduce potential drawdowns by reacting to changes in market conditions. The predominant approach in previous studies has been to specify in advance a static decision rule for changing the allocation based on the state of financial markets or the economy. In this article, model predictive control (MPC) is used to dynamically optimize a portfolio based on forecasts of the mean and variance of financial returns from a hidden Markov model with time-varying parameters. There are computational advantages to using MPC when estimates of future returns are updated every time a new observation becomes available, since the optimal control actions are reconsidered anyway. MPC outperforms a static decision rule for changing the allocation and realizes both a higher return and a significantly lower risk than a buy-and-hold investment in various major stock market indices. This is after accounting for transaction costs, with a one-day delay in the implementation of allocation changes, and with zero-interest cash as the only alternative to the stock indices. Imposing a trading penalty that reduces the number of trades is found to increase the robustness of the approach.     

Cyclicality in losses on bank loans

Based on unique data we show that macro variables, the default rate and loss given default of bank loans share common cyclical components. The innovation in our model is the distinction between loans with either severe or mild losses. The variation in the proportion of these two types drives the cyclic behavior of the loss given default and constitutes the links with the default rate and macro variables. These links vary according to loan and borrower characteristics. During downturns, the proportion of defaults with severe losses increases, but the distribution of losses conditional on their being mild or severe does not change. although loans are monitored more closely than bonds and are more senior, the cyclical variation in their losses resembles those for bonds, albeit around a lower average level. This variation leads to an increase in the capital reserves required for loan portfolios.     

Valuing Curb Appeal

The Journal of Real Estate Finance and Economics - We recover the value of curb appeal in residential housing by using photos obtained from Google Street View, a deep learning classification...     

Do data policy restrictions inhibit trade in services?

Review of World Economics - This paper examines whether restrictive data policies are related to trade in services. The authors have collected comparable information on a variety of policy measures...     

Ist das österreichische Rentensystem nachhaltig?

Wirtschaftsdienst - In der deutschen Debatte zur Rentenpolitik wird in letzter Zeit immer wieder auf das Beispiel Österreich verwiesen. Das hohe österreichische Leistungsniveau provoziert...