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281.
282.
For a dose finding study in cancer, the most successful dose (MSD), among a group of available doses, is that dose at which the overall success rate is the highest. This rate is the product of the rate of seeing non-toxicities together with the rate of tumor response. A successful dose finding trial in this context is one where we manage to identify the MSD in an efficient manner. In practice we may also need to consider algorithms for identifying the MSD which can incorporate certain restrictions, the most common restriction maintaining the estimated toxicity rate alone below some maximum rate. In this case the MSD may correspond to a different level than that for the unconstrained MSD and, in providing a final recommendation, it is important to underline that it is subject to the given constraint. We work with the approach described in O'Quigley et al. [Biometrics 2001; 57(4):1018-1029]. The focus of that work was dose finding in HIV where both information on toxicity and efficacy were almost immediately available. Recent cancer studies are beginning to fall under this same heading where, as before, toxicity can be quickly evaluated and, in addition, we can rely on biological markers or other measures of tumor response. Mindful of the particular context of cancer, our purpose here is to consider the methodology developed by O'Quigley et al. and its practical implementation. We also carry out a study on the doubly under-parameterized model, developed by O'Quigley et al. but not 相似文献
283.
John Ermisch 《Journal of population economics》2008,21(4):827-853
The paper presents a model of a non-resident father’s child support and contact with his child, which combines the public
good treatment of “child quality” with “trade” in father–child contact time in a setting of non-cooperative interaction. It
predicts that father’s income and mother’s non-labour income should have exactly the same effect on the frequency of father–child
contact if he chooses to make lump sum payments to the mother. If he does not or there is a binding child support payment
order, they have effects opposite in direction. A higher binding support order reduces father–child contact but may well raise
“child quality”.
相似文献
John ErmischEmail: |
284.
William Lavely 《Population and development review》2001,27(4):755-769
The 2000 census of China has several notable innovations, including a sample long form containing detailed items on migration, housing, and employment. Preliminary data indicate rapid urbanization and continued rapid social change in the 1990s, and apparent success in the government's drive to curtail population growth. Although a post‐enumeration survey indicates that overall data quality is good, the rise of a mobile “floating population” and pressures of the birth planning program caused problems for the enumeration of migrants and infants. Data released to date have been silent on two important issues, fertility and rising sex ratios. 相似文献
285.
Van Imhoff Evert Van Solinge Hanna Flim Bert Jan 《Population research and policy review》2001,20(6):457-481
Compared to other countries that have suffered from the Nazioccupation, the destructive impact of the Holocaust on theJewish population has been particularly strong in the Netherlands. This paper gives a demographicreconstruction of the Jewish population in the Netherlands by the end of the war (1945),disaggregated by age and sex. The reconstruction is based on two approaches: a forwardprojection 1941–1945, starting from registration data supplemented by information onHolocaust losses; and a backward projection 1966–1945, starting from an enumerationof Halachic Jews carried out in 1966. The two approaches yieldtwo estimates that are comfortingly similar. 相似文献
286.
Population and Environment - This article is a synopsis of a UN study, with emphasis on Italy and the United States. In March, 2000, the United Nations Population Division published a 143-page... 相似文献
287.
John Stillwell Martin Bell Marcus Blake Oliver Duke-Williams Phil Rees 《Journal of Population Research》2001,18(1):19-39
This paper explores the impact of net migration in Australia and the United Kingdom using measures of migration effectiveness
computed from period-age migration data for four consecutive five-year periods. Results reported in Part 1 of this paper (Stillwellet al. 2000) suggest that while the overall effectiveness of net migration at the scale of city regions has declined over the twenty-year
period in both countries, important geographical variations are evident. Part 2 considers how patterns of migration effectiveness
vary by age and presents a single classification of all the city regions on the basis of age-specific effectiveness. More
detailed analysis includes spatial patterns for particular age groups and net migration profiles of selected regions. Cohort
effects are shown to be important for explaining changes between time periods in these regions. 相似文献
288.
Two related streams of criticism of the analytic hierarchy process (AHP) have not yet been satisfactorily resolved, although both date from the early 1980s. The first relates to ambiguity in the meaning of the relative importance of one criterion as compared to another. The second is concerned with reversals of rank alleged to be possible when new options are introduced in an AHP problem. Both proponents and critics of AHP agree that rank reversals occur, but disagree on the legitimacy of such reversals. This paper shows that there is a necessary correspondence between the manner in which criteria importances are interpreted and computed and the manner in which the weights of the options under each criterion are normalized. In general, if this relationship is ignored, incorrect weights are generated for options under consideration regardless of whether new options are added or deleted. A rank reversal on the addition of an option is merely symptomatic of this fact, and such reversals do not occur when the correspondence condition is met. 相似文献
289.
Abstract The highly volatile auction system in Australia accounts for 85 percent of ex‐farm wool sales, with the remainder sold by forward contract, futures, and other hedging methods. In this article, against the background of an extensive literature on price risk strategies, we investigate title behavioral factors associated with producers' adoption of price risk‐management strategies (specifically futures and forward contracts) for selling wool. This research presents a behavioral model based on Diffusion of Innovations, the Theory of Reasoned Action, and the Theory of Planned Behavior. We found that the auction system is used as a price risk‐management tool because other selling methods are considered more risky. We also report on a curious relationship between risk and complexity in terms of wool producers' intentions to use forward contracts. We explored sociological factors in conjunction with focus‐group data in an attempt to understand this relationship. This exercise yielded some interesting findings on the impact that trust, habit, social cohesion, and networks have on decision making in the rural community. The significance of this article lies in its application of core sociological theory in a new research context: the Australian wool industry. 相似文献
290.
This study analyzes the image repair discourse by Chinese Health Minister Zhang Wenkang's discourse on SARS. The minister faced several accusations: the SARS outbreak was growing, the Chinese government had covered up the severity of this problem, the Chinese government ignored Taiwanese who suffered from SARS, and the Health Ministry provided information that was neither timely nor accurate. He employed several image repair strategies (denial, defeasibility, bolstering, minimization, differentiation, attack accuser, and corrective action). However, his messages were contradictory and apparently related on false information, so his efforts were unsuccessful and he was stripped of his office. 相似文献