Intraday Value at Risk (IVaR) using tick-by-tick data with application to the Toronto Stock Exchange

This paper investigates the use of tick-by-tick data for intraday market risk measurement. We propose a method to compute an Intraday Value at Risk based on irregularly spaced high-frequency data and an intraday Monte Carlo simulation. A log-ACD–ARMA–EGARCH model is used to specify the joint density of the marked point process of durations and high-frequency returns. We apply our methodology to transaction data for three stocks actively traded on the Toronto Stock Exchange. Compared to traditional techniques applied to intraday data, our methodology has two main advantages. First, our risk measure has a higher informational content as it takes into account all observations. On the total risk measure, our method allows for distinguishing the effect of random trade durations from the effect of random returns, and for analyzing the interaction between these factors. Thus, we find that the information contained in the time between transactions is relevant to risk analysis, which is consistent with predictions from asymmetric-information models in the market microstructure literature. Second, once the model has been estimated, the IVaR can be computed by any trader for any time horizon based on the same information and with no need of sampling the data and estimating the model again when the horizon changes. Backtesting results show that our approach constitutes reliable means of measuring intraday risk for traders who are very active in the market.     

Price competition during and after promotions

We provide a framework for setting regular prices and using promotional discounts in a duopoly where long‐term promotional effects are present and the firms' pricing and promotional strategies are common knowledge (e.g., as in online markets). We show that at equilibrium, the two firms may not promote and instead adopt an Everyday Low Price (EDLP) strategy. Consumers' tendency to stockpile promoted products, the level of brand loyalty and product differentiation, and the possibility of a postpromotional sales increase critically influence regular prices, price discount rates, and profits. Under some conditions consumer stockpiling intensifies promotional competition and reduces firms' profits while the possibility of attracting new consumers reduces the need to heavily promote and ensures better profits. Managerial implications are discussed. Copyright © 2007 ASAC. Published by John Wiley & Sons, Ltd.     

Asset pricing models with errors-in-variables

This paper revisits Fama and French [Fama, Eugene F., French, Kenneth R., (1993) Common risk factors in the returns on stock and bonds. Journal of Financial Economics 33 (1), 3–56] and Carhart [Carhart, Mark M., 1997. On persistence in mutual fund performance. Journal of Finance 52 (1), 57–82] multifactor model taking into account the possibility of errors-in-variables. In their well known paper, Fama and French [Fama, Eugene F., French, Kenneth R., 1997. Industry costs of equity. Journal of Financial Economic 43 (2), 153–193] concluded that estimates of the cost of equity for the three-factor model of FF (1993) were imprecise. We argue that this imprecision is even more severe because of the pervasive effects of measurement errors. We propose Dagenais and Dagenais [Dagenais, Marcel G., Dagenais, Denyse L., 1997. Higher moment estimators for linear regression models with errors in the variables. Journal of Econometrics 76 (1–2), 193–221] higher moments estimator as a solution. Our results show that estimates of the cost of equity obtained with Dagenais and Dagenais estimator differ sharply from popular OLS estimates and shed a new light on performance attribution and abnormal performance (α). Adapting the Generalized Treynor Ratio, recently developed by Hübner [Hübner, Georges, 2005. The generalized treynor ratio. Review of Finance 9 (3), 415–435], we show that the performance of managed portfolios with multi-index models should be revisited in presence of errors-in-variables.     

Energiesparen: Warum wird Beratung gefördert?

Home renovation is generally asserted to be a highly effective means to increase residential energy efficiency and thereby contribute to climate protection from reduced energy consumption. As part of a larger package of measures in the residential sector, the German government is consequently providing financial support for home audits from recognized energy experts who provide advice on retrofitting options. To date, the question concerning the effectiveness these home audits has largely escaped empirical scrutiny. The present paper fills this void by providing evidence for considerable free-rider effects within the home audit program, yielding serious reservations with respect to both the effectiveness of the program and its fiscal costs. Moreover, given the substantial differences between the gross- and net effects of home audits that are revealed by this analysis, the program’s contribution to climate protection and thereby the central justification for the associated government outlays is called into question. The social benefit of the program emerges only from those retrofits that would not have been undertaken in the absence of the home audit.     

Product Unbundling in the Travel Industry: The Economics of Airline Bag Fees

This paper provides theory and evidence on airline bag fees, offering insights into a real‐world case of product unbundling. The theory predicts that an airline's fares should fall when it introduces a bag fee, but that the full‐trip price (the bag fee plus the new fare) could either rise or fall. The empirical evidence presented in the paper provides strong confirmation of the first prediction. The data also suggest that the average fare falls by less than the bag fee itself so that the full price of a trip rises for passengers who choose to check bags.     

Schlechter Wein in alten Schläuchen—Eine Replik auf Helmedag

In der Januarausgabe des WIRTSCHAFTSDIENST ver?ffentlichten wir einen Aufsatz von Professor Fritz Helmedag über die „Abh?ngigkeit der Besch?ftigung von Steuern, Budgetdefiziten und L?hnen“. Hierzu eine Replik von Professor Bernd Lucke und eine Erwiderung von Professor Fritz Helmedag.     

Spieltheoretische Analyse von Konflikt und Kooperation

Mit dem diesj?hrigen Nobelpreis für Wirtschaftswissenschaften wurden die Forscher Robert Aumann und Thomas Schelling für ihre spieltheoretischen Beitr?ge zu Konflikt und Kooperation in (wiederholten) Spielen ausgezeichnet. Inwieweit haben die beiden Forscher die Spieltheorie weiterentwickelt? Auf welche zentralen sozialwissenschaftlichen Fragestellungen lassen sich ihre Erkenntnisse anwenden?     

Small businesses as a research subject: Some reflections on knowledge of small businesses and its effects on economic theory

Most economists agree in their view of small and medium-sized enterprises, or small businesses (SMEs), as a marginal scientific subject. They may go so far as to ignore them, either because they think these economic units do not lend themselves to conventional economic studies — studies which, for instance, take into account the sacred cow theory of economies of scale — or because they see them as being not really different from big businesses.However, at least a few economists have recognized, first, the many characteristics differentiating SMEs from big firms, and second, their increasing importance in terms of numbers and job creation within economies. Among these few, Schumpeter was one of the first to show the importance of entrepreneurs and SMEs as the main variable of change in an economy. Simon and Lucas also explained the difference between small and big firms through the differing abilities required by managers to run them. Penrose looked at the question from another point of view by highlighting the interstices taken up by SMEs to fulfil needs that cannot be fulfilled by bigger units. Critics of the theory of economies of scale showed that such economies may be offset by a number of diseconomies, thus justifying the efficiency of many SMEs. More recently, Mills and Schumann suggested that SMEs compensate for their lack of economies of scale by their production flexibility, particularly in today's turbulent economy.The limits of traditional economic theory are clearly demonstrated by the fact that it does not take account of all these theories, concepts and ideas. It thus neglects a number of important economic phenomena, including the persistence and current expansion of SMEs. Consideration of such phenomena may lead to the development of a new economic theory based on the concepts of instability and contingency, together with the behaviour of entrepreneurs and small firms, thus tending to contradict, in particular, the concept of equilibrium in conventional economic theory.A first version of this paper has been presented as invited speaker at the symposium of TETRA Group at Lyon, France, 30–31 May 1990. I thank the colleagues Fritz Rieger, Frances Solé Parrellada, Jacques Filion and the two referees for their very interesting suggestions on a preliminary second version.     

It's a secret: Marketing value and the denial of availability

Marketing thrives on secrets, yet surprisingly little formal attention has been paid to how the marketing of secrecy and the secrecy of marketing can play a significant role in contemporary organizations. We draw upon the fields of organizational studies, psychology, and marketing to develop a typology of secrets that reflects their marketing value and their knowledge value. Marketing secrets can have value to the firm (strategic value), to the customer (marketing value), or to both parties. Based on these two dimensions, we identify four different types of marketing secrets: (1) appealing secrets have high strategic value, as well as high marketing value; (2) mythical secrets mean little to the firm but a lot to the customer; (3) plain secrets are critical to the firm but are irrelevant to customers; and (4) weak secrets have neither strategic value nor marketing value. Our typology enables academics to formulate research questions regarding secrecy in marketing, and serves as a guide for practitioners in the construction of strategies that can exploit the strategic value of secrets by ‘romancing’ them, and increase their knowledge value by ‘educating’ the secrets.