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991.
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993.
The purpose of this paper is to examine changes in stock return variances following option introduction. The sample consists of National Market System stocks and employs both transaction returns and returns based on bid and ask quotes. Variances are decomposed into portions attributable to bid-ask spreads, return autocorrelations, and intrinsic variances. Spreads play a negligible role in explaining variance changes. A generally positive component to short-term autocorrelations falls following option introduction, increasing variances over short holding periods. Intrinsic variances fall prior to the October 1987 crash, but do not change after the crash with option introduction.  相似文献   
994.
A model to simulate the costs and returns of an individual dairy cow over 14 years under various assumptions of genetic potential, health status and management was developed especially to evaluate the effects of diseases that reduce production and reproduction efficiency and to evaluate alternative management interventions. Data were collected from the Food Animal Health Resource Management System (FAHRMX), Today's Electronic Planning (TELPLAN), Today's Electric Farm Accounting (TELFARM) databases and secondary sources at Michigan State University. A case study of cystic ovaries was analysed using the model. The results showed that it is more economical to treat cystic ovaries than not to treat, and treatment with Gonadotropin Releasing Hormone (GNRH) was superior to Human Chrionic Gonadotropin (HCG). Four to five lactations were the optimum for keeping a dairy cow to replacement and it was estimated that there is a loss of US$0.45 per day of extended calving interval (days open beyond the optimal 70 days).  相似文献   
995.
The behaviour of stock prices on the Colombo Stock Exchange (CSE) is examined with a view to determine its consistency with the weak form of the Efficient Markets Hypothesis (EMH). Runs, Autocorrelation and Cointegration tests are applied to daily, weekly and monthly CSE index data for the period of January 1991–November 1996. Results of Runs, Correlation and Cointegration tests overwhelmingly reject the serial independence hypothesis, leading to the conclusion that the behaviour of stock prices in the Colombo Stock Exchange is not consistent with the weak form of the Efficient Markets Hypothesis. Tests of the-day-of-the-week-effect, however, show that there is no evidence of such a phenomenon on the Colombo Stock Exchange stock prices. Results of the tests of the-month-of-the-year-effect lead to the conclusion that CSE prices do not display any month-specific behaviour.  相似文献   
996.
Migration from the mountain areas of pre-industrial Europe has been seen as the product of poverty. While hardship controlled the strategies of the more marginalized households, better placed families used their migration experience to establish themselves in commerce. Over generations they used contacts and kinship systems to develop important informal trading networks. It is difficult to establish the effects of this hidden activity on local mountain economies, but dowry payments and post mortem inventories are used to expose the impact of inflowing capital and its circulation.  相似文献   
997.
Abstract:   This paper examines the characteristics of firms that account for deferred tax liabilities related to government investment grants under an extended adoption timing period. Not only the recognition but also the timing decision is associated with changes in future performance and changes in the debt structure. Recognisers outperform non‐recognisers in the future, while early recognition is related to post recognition performance but only for those firms that currently perform well. Changes in the balance sheet structure are also related to both decisions. Firms with recent increases in the debt level tend to postpone recognition, while currently well‐performing firms that increase their future debt level are less likely to recognise deferred taxes.  相似文献   
998.
The economic impact of adopting herd health programs for mastitis and reproduction by small-scale dairy producers of Central Thailand was assessed using a policy analysis matrix (PAM). Following a reduction in the incidence of bovine disease on adopter farms, an increase in private net profits is observed. More importantly the social costs of supporting dairy farmers is reduced; the PAM effective protection coefficient was reduced by 35% for mastitis program adopters and by 44% for reproductive program adopters, indicating improved social efficiency of dairy policy. Other indicators of efficiency and policy implications are discussed.  相似文献   
999.
1000.
Earnings Performance and Discretionary Disclosure   总被引:12,自引:1,他引:11  
While the influence of earnings performance on disclosure is a fundamental issue in the disclosure literature, our understanding of this influence is limited. In this paper, I examine a comprehensive set of disclosures from a sample of firms experiencing an extended period of seasonally adjusted earnings increases. I study how these firms adjust disclosure in response to earnings increases, how disclosure changes as the period of strong earnings performance nears an end and how firms disclose during a subsequent period of earnings decline. I find an increase in disclosure during the period of increased earnings. This increase is pervasive across all types of disclosure and tends to be bundled with earnings announcements. The market responds positively to this disclosure. Firms continue to disclose at a high level as they approach earnings declines. However, they shift to disclosures that focus on the positive short-term results and do not discuss the impending decreases. While this behavior is systematic, the market does not appear to anticipate the subsequent earnings declines. Once the firms announce earnings declines, the magnitude of disclosure returns to the level provided prior to the increased earnings.  相似文献   
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