Monitoring the parameter changes in general ARIMA time series models

We propose methods for monitoring the residuals of a fitted ARIMA or an autoregressive fractionally integrated moving average (ARFIMA) model in order to detect changes of the parameters in that model. We extend the procedures of Box & Ramirez (1992) and Ramirez (1992) and allow the differencing parameter, d to be fractional or integer. Test statistics are approximated by Wiener processes. We carry out simulations and also apply our method to several real time series. The results show that our method is effective for monitoring all parameters in ARFIMA models.     

TEEAL and AGORA: Improving Access to Agricultural Journals in Low-Income Countries

The Essential Electronic Agricultural Library (TEEAL) and Access to Global Online Research in Agriculture (AGORA) are programs that will provide low-income countries with access to agricultural journal literature that advances their agricultural research and education objectives. Developed by Cornell University's Mann Library and launched in 1999, TEEAL is a self-contained agricultural research library with full-text articles and graphics of 140 major journals related to agriculture from 1993 through 2003, stored and indexed on over 400 CD-ROMs. In mid-2005, most of the collection also became available for use over local area networks. Launched in October 2003, AGORA is an Internet-based journal delivery system led by the UN Food and Agriculture Organization (FAO), with Mann Library as a principal partner. AGORA offers almost 800 journals from twenty-seven international publishers to 113 low-income countries and territories for free or a nominal fee.     

Patterns in Cross Shopping for Groceries and their Implications for Co-operation in Retail Location

One determinant of the success of a retail outlet is its location. The location strategies adopted by many retailers of convenience products, including those marketing groceries, have been based upon the principle of siting stores away from competition. Recent moves by leading grocery retailers to develop out of town and other sites jointly, where they would trade side by side, mean that methods are needed to appraise the selection of location partners to supplement or replace traditional, spatial analyses. A method based on similarity of image and cross-shopping behaviour is proposed and tested on two substantial data bases. A concept, drawn from theory on brand switching, that customers would treat outlets seen as similar in a similar way, is found not to apply to source switching. Source switching behaviour is found instead to vary with the source itself, according to two distinct patterns. In one, shoppers cross shop more to retailers perceived to be similar; in the other, shoppers cross shop more to retailers perceived to be different. The strategies currently adopted by four grocery retailers in joint site development are appraised against the model of source switching that can be defined from these patterns. Some location alliances are predicted to be potentially more valuable to one partner than another both in the short and long term. The anomalies identified in the selection of location partners are analysed by reference to concepts drawn from the literature on co-operation. Two different types of relationship exist between the various retail partners; a longer term alliance at each site and shorter co-operation between head offices. It is suggested that the nature of the second could prejudice the outcome of the first.     

Married women's retirement behavior

In this paper we examine the economic and family determinants of married women's retirement behavior. A life cycle model of wives' retirement decisions is tested empirically using data on working married women from the Longitudinal Retirement History Survey. This exploratory analysis indicates that family considerations are more important in wives' retirement decisions than own economic opportunities. These findings contrast with those obtained previously for male workers and if substantiated by other research could have important implications for policy questions regarding pension and Social Security reform.This research was funded by the 1986–7 Small Grants Program sponsored by the University of Wisconsin, Madison, Institute for Research on Poverty, the Cornell Institute of Social and Economic Research, and the New York State School of Industrial and Labor Relations. Excellent programming assistance was provided by Vivian Fields. We are grateful to Glen Cain and two anonymous referees for useful comments. Any opinions expressed herein are those of the authors and not those of the above-named persons or institutions.     

Strategic planning for the board

Although the planning operation is regarded by some observers as unrealistic in conditions of rapid change and increasing competition, the discipline of strategic thinking and the need for strategic leadership continue to be of vital importance. The author examines the purpose of the Board of Directors and its role in the management of strategy.     

The changing structure of food retailing in europe: the implications for strategy

European food retailers have increased their scale and scope while concentrating sales into large stores. Strategic implications include the need for scale to compete and organisational relationships to move from supply push to demand pull retailing. Consequences are different for private label and for branded manufacturers, who must respond to the demands of retail supply chains whilst retaining control of product development. Further concentration in both sectors is likely. Consumers are more mobile, but more captive to the retailer in store. Public policy makers are challenged to find new measures of retail power and both allow for innovation and ensure equitable shopping opportunities.