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In 1991 the FCC implemented a price cap plan for local exchange carriers' interstate access service designed to deal with the regulatory boundaries problem arising from the breakup of AT&T in 1984. The experience with the price cap plan demonstrates the difficulty of predicting productivity growth accurately and makes clear that regulators cannot depend upon a pure price cap plan to keep prices within a reasonable range of costs. With periodic reviews to readjust plan parameters, however, a price cap plan can maintain the rate-of-return close to the target rate-of-return without diminishing the price cap plan's incentives for efficient production. A simple method of recalculating the X-factor based on the rate-of-return over the previous three years worked well in simulations. If this procedure had been used over the price cap period 1991 to 2000, prices would have been 20 percent lower and expenditures on LECs' telecommunications service subject to a price cap would have been $3.8 billion lower.  相似文献   
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South Korea sent troops to Iraq not because of any perceived threat from an Iraqi nuclear programme, but to seek influence over American foreign policy towards North Korea. At no point did the general public support the American invasion and war in Iraq; most South Koreans also opposed sending troops to Iraq. However, the government chose to send first non-combat and later combat troops to Iraq, and the public approved of the former choice and support was growing for the latter. The liberal President Roh Moo-Hyun had to persuade the public on this issue, even in opposition to his core supporters, risking political isolation. What the public and the President aimed at was a peaceful resolution of the North Korean nuclear issue and business opportunities. The national interest that South Korea pursued in sending troops to Iraq was policy influence over the US guarantee not to use military power against North Korea.  相似文献   
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While the concepts of race and ethnicity have been abused historically, they are potentially invaluable in epidemiology and public health. Epidemiology relies upon variables that help differentiate populations by health status, thereby refining public health and health care policy, and offering insights for medical science. Race and ethnicity are powerful tools for doing this. The prerequisite for their responsible use is a society committed to reducing inequalities and inequities in health status. When this condition is met, it is irresponsible not to utilize these concepts.  相似文献   
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The present study measured the existence of traumatic stress symptomatology as reported by certified law enforcement officers within the State of Delaware. A questionnaire was devised which documented age, sex, race, education, years of service, marital status, children, rank, position, and shift work. The questionnaire was divided into parts which assessed the exposure and the frequency of specific traumatic incidents experienced in the line of duty, and the frequency of experienced traumatic symptomatology criteria: re-experiencing, numbing, and arousal.  相似文献   
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