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21.
Abstract. This research re-examines whether there are differences in the forecast accuracy of financial analysts through a comparison of their annual earnings per share forecasts. The comparison of analyst forecast accuracy is made on both an ex post (within sample) and an ex ante (out of sample) basis. Early examinations of this issue by Richards (1976), Brown and Rozeff (1980), O'Brien (1987), Coggin and Hunter (1989), O'Brien (1990), and Butler and Lang (1991) were ex post and suggest the absence of analysts who can provide relatively more accurate forecasts over multiple years. Contrary to the results of prior research and consistent with the belief in the popular press, we document that differences do exist in financial analysts' ex post forecast accuracy. We show that the previous studies failed to find differences in forecast accuracy due to inadequate (or no) control for differences in the recency of forecasts issued by the analysts. It has been well documented in the literature that forecast recency is positively related to forecast accuracy (Crichfield, Dyckman, and Lakonishok 1978; O'Brien 1988; Brown 1991). Thus, failure to control for forecast recency may reduce the power of tests, making it difficult to reject the null hypothesis of no differences in forecast accuracy even if they do exist. In our analysis, we control for the differences in recency of analysts' forecasts using two different approaches. First, we use an estimated generalized least squares estimation procedure that captures the recency-induced effects in the residuals of the model. Second, we use a matched-pair design whereby we measure the relative forecast accuracy of an analyst by comparing his/her forecast error to the forecast error of another randomly selected analyst making forecasts for the same firm in the same year on or around the same date. Using both approaches, we find that differential forecast accuracy does exist amongst analysts, especially in samples with minimum forecast horizons of five and 60 trading days. We show that these differences are not attributable to differences in the forecast issuance frequency of the financial analysts. In sum, after controlling for firm, year, forecast recency, and forecast issuance frequency of individual analysts, the analyst effect persists. To validate our findings, we examine whether the differences in the forecast accuracy of financial analysts persist in holdout periods. Analysts were assigned a “superior” (“inferior”) status for a firm-year in the estimation sample using percentile rankings on the distribution of absolute forecast errors for that firm-year. We use estimation samples of one- to four-year duration, and consider two different definitions of analyst forecast superiority. Analysts were classified as firm-specific “superior” if they maintained a “superior” status in every year of the estimation sample. Furthermore, they were classified as industry-specific “superior” if they were deemed firm-specific “superior” with respect to at least two firms and firm-specific “inferior” with respect to no firm in that industry. Using either definition, we find that analysts classified as “superior” in estimation samples generally remain superior in holdout periods. In contrast, we find that analysts identified as “inferior” in estimation samples do not remain inferior in holdout periods. Our results suggest that some analysts' earnings forecasts should be weighted higher than others when formulating composite earnings expectations. This suggestion is predicated on the assumption that capital markets distinguish between analysts who are ex ante superior, and that they utilize this information when formulating stock prices. Our study provides an ex ante framework for identifying those analysts who appear to be superior. When constructing weighted forecasts, a one-year estimation period should be used because we obtain the strongest results of persistence in this case. 相似文献
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This paper applies principles of transition to land tenure and squatting in South Africa. Political transition in South Africa reassigned political property rights, which produced contestable, and rent‐seeking incentives for squatting as a means to privatize land and redistribute wealth. Government failure to establish and protect private property rights in a squatter camp resulted in common‐pool problems that resisted private and public resolution with consequent rent dissipation and social loss. In response to this retreat from duty, informal agents emerged to claim their own share of the prize. Without enforceable rules of capture, the growth of squatter camps in South Africa will continue. JEL classification: D7, H8, K1, K4, R1, R4. 相似文献
24.
This article reviews the law regarding Title VII employment discrimination protection from religious discrimination. The issues surrounding the principal legal protection in this regard are explored in the context of a recent controversial case in which an author, Forrest Mims, was not hired as a regular contributor forScientific American magazine, ostensibly because of his belief in the theory of creation over the theory of evolution. The definition of what constitutes a protected religious belief or practice is seen to have expanded over time. However, a belief in creationism is not necessarily seen as being tantamount to a religious belief under present legal interpretation of Title VII. The implications of this finding for future needed Title VII revision are discussed. 相似文献
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Rudy K. Moenaert William E. Souder Arnoud De Meyer Dirk Deschoolmeester 《Journal of Product Innovation Management》1994,11(1):31-45
Rudy Moenaert, William Souder, Arnoud De Meyer, and Dirk Deschoolmeester report the results of their study of forty technologically innovative Belgian companies to examine the interaction between marketing and R&D. They studied one commercially successful and one commercially unsuccessful technological product innovation project in each participating company and collected data from one marketing and one R&D respondent per project. Communication flows between marketing and R&D are increased under conditions involving formalization of projects, decentralization, positive interfunctional climate, and role flexibility. 相似文献
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D. P. O'Brien 《英国劳资关系杂志》1992,30(2):253-285
This paper is concerned with one central question: the choice between theories, and the role played by data in that choice. It deals with the uses economists may make of data and the importance of understanding the institutional basis that gives rise to the data - an area in which labour economists have traditionally been particularly strong - and with the relevance of assumptions. It deals with the ultimate need to choose between competing theories (despite the role of conventionalism) on the basis of data rather than retreating into a comfortable 'methodological pluralism'. It considers the role of test replication, with reference to the practice in natural science (and its role there in checking scientific fraud) and concludes that, despite extensive technical problems of testing, economists have to accept a data check if the rhetoric of mathematical technicality is not to overwhelm the need to explain. Parallels are drawn with experience in physics (and the implications of the development of Chaos and Catastrophe for a naively predictionist view are noted), medicine and history (of which, it is argued, modern economists are far too neglectful). 相似文献
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