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Summary A sequential testing procedure called 2-SPRT for the meanμ of the negative binomial distribution with known exponentk is presented. For any fixedμ 0(μ 1<μ 0<μ 2), the 2-SPRT provides an asymptotic solution to the modified Kiefer-Weiss problem. Determination ofμ 0 such that the test provides an approximate solution to the Kiefer-Weiss problem is described. The behavior of the 2-SPRT and the Sequential Probability Ratio Test is investigated using Monte Carlo methods. The error probabilities and the average sample numbers are compared. All the computations were carried out on the Alabama Supercomputer.  相似文献   
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This paper focuses on the construction of forecasts over long horizons where a typical long-horizon forecast might span four years using 20 to 40 years’ data. It is argued that the presence of persistence in the form of unit or near-unit autoregressive roots poses substantial difficulties for long-horizon interval and point forecasting. These difficulties may not be overcome even by efficient pre-testing or model-selection procedures and might, in general, lead to point forecasts with large asymptotic root mean squared errors and undesirably wide prediction intervals.  相似文献   
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A growing awareness of workplace hazards and identification of airborne contaminants, coupled with a changing safety and health regulatory environment, created an unexpected demand for new and innovative respirators in the early 1980s. 3M's Occupational Health and Environmental Safety Division broke new ground by taking the team concept further than ever before in the company. The division's Action Teams successfully designed, built and introduced products in less than half the time it would have taken previously. Robert Hershock, Charles Cowman and Douglas Peters describe how 3M learned important lessons about team selection, training, performance and motivation, the importance of project sponsors, and the role of middle management.  相似文献   
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To compensate for low civil service incomes, most lecturers at Indonesia's public universities hold one or more other jobs. The career path of the typical lecturer is away from teaching: the higher the classification the greater is the number of outside jobs and the smaller is the time devoted to undergraduate teaching. In effect, public universities cannot now compete for the time of their lecturers. Indonesia has been attempting to increase the quality of undergraduate education by investing in further education of lecturers. Our findings show that such efforts will be futile unless concomitant changes are also made on the demand side.  相似文献   
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This paper surveys the theoretical and empirical literature on the relationship between advertising, fees and quality in the self–regulating professions. Much of the literature is derived from the perspective of advertising as an information–enhancing device, helping to reduce the information asymmetry between professional and client. This is consistent with the majority of the empirical studies which suggest that advertising tends to have a downward effect on professional fees, with little if any adverse effect on quality. There are, however, important issues of method and measurement which may lessen the force of this conclusion  相似文献   
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In 1986 The O.M. Scott & Sons Company, the largest producer of lawn care products in the U.S., was sold by the ITT Corporation in a divisional leveraged buyout. The company was founded in Marysville, Ohio in 1870 by Orlando McLean Scott to sell farm crop seed. In 1900, the company began to sell weedfree lawn seed through the mail. In the 1920s, the company introduced the first home lawn fertilizer, the first lawn spreader, and the first patented bluegrass seed. Today, Scott is the acknowledged leader in the “do-it-yourself” lawn care market, with sales of over $300 million and over 1500 employees. Scott remained closely held until 1971, when it was purchased by ITT. The company then became a part of the consumer products division of the huge conglomerate, and operated as a wholly-owned subsidiary for 14 years. In 1984, prompted by a decline in financial performance and rumors of takeover and liquidation, ITT began a series of divestitures. Over the next two years, total divestitures exceeded $2 billion and, after years of substandard performance, ITT's stock price significantly outperformed the market. On November 26, 1986, in the midst of this divestiture activity, ITT announced that the managers of Scott, along with Clayton & Dubilier (C & D), a private firm specializing in leveraged buyouts, had agreed to purchase the stock of Scott and another ITT subsidiary, the W. Atlee Burpee Company. The deal closed on December 30. Clayton & Dubilier raised roughly $211 million to finance the purchase of the two companies. Of that $211 million, almost $191 milion, or 91% of the total, was debt: bank loans, subordinated notes, and subordinated debentures. The $20 million of new equity was distributed as follows: roughly 62% of the shares were held by a C & D partnership, 21% by Scott's new subordinated debtholders, and 17.5% by Scott management and employees. After this radical change in financial structure and concentration of equity ownership, Scott's operating performance improved dramatically. Between the end of December 1986 and the end of September 1988, sales were up 25% and earnings before interest and taxes (EBIT) increased by 56%. As shown in Table 1, this increase in operating earnings was not achieved by cutting back on marketing and distribution or R & D. In fact, spending on marketing and distribution increased by 21% and R & D spending went up by 7%. Capital spending also increased by 23%.  相似文献   
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