39 research outputs found
An integer programming Model for the Hospitals/Residents Problem with Couples
The Hospitals/Residents problem with Couples (hrc) is a generalisation of the classical Hospitals/Residents problem (hr) that is important in practical applications because it models the case where couples submit joint preference lists over pairs of (typically geographically close) hospitals. In this paper we give a new NP-completeness result for the problem of deciding whether a stable matching exists, in highly restricted instances of hrc. Further, we present an Integer Programming (IP) model for hrc and extend it the case where preference lists can include ties. Further, we describe an empirical study of an IP model for HRC and its extension to the case where preference lists can include ties. This model was applied to randomly generated instances and also real-world instances arising from previous matching runs of the Scottish Foundation Allocation Scheme, used to allocate junior doctors to hospitals in Scotland
The Hospitals/Residents Problem with Couples: complexity and integer programming models
The Hospitals / Residents problem with Couples (hrc) is a generalisation of the classical Hospitals / Residents problem (hr) that is important in practical applications because it models the case where couples submit joint preference lists over pairs of (typically geographically close) hospitals. In this paper we give a new NP-completeness result for the problem of deciding whether a stable matching exists, in highly restricted instances of hrc, and also an inapproximability bound for finding a matching with the minimum number of blocking pairs in equally restricted instances of hrc. Further, we present a full description of the first Integer Programming model for finding a maximum cardinality stable matching in an instance of hrc and we describe empirical results when this model applied to randomly generated instances of hrc
The Dutch health insurance reform: switching between insurers, a comparison between the general population and the chronically ill and disabled
Background: On 1 January 2006 a number of far-reaching changes in the Dutch health insurance
system came into effect. In the new system of managed competition consumer mobility plays an
important role. Consumers are free to change their insurer and insurance plan every year. The idea
is that consumers who are not satisfied with the premium or quality of care provided will opt for
a different insurer. This would force insurers to strive for good prices and quality of care.
Internationally, the Dutch changes are under the attention of both policy makers and researchers.
Questions answered in this article relate to switching behaviour, reasons for switching, and
differences between population categories.
Methods: Postal questionnaires were sent to 1516 members of the Dutch Health Care Consumer
Panel and to 3757 members of the National Panel of the Chronically ill and Disabled (NPCD) in
April 2006. The questionnaire was returned by 1198 members of the Consumer Panel (response
79%) and by 3211 members of the NPCD (response 86%). Among other things, questions were
asked about choices for a health insurer and insurance plan and the reasons for this choice.
Results: Young and healthy people switch insurer more often than elderly or people in bad health.
The chronically ill and disabled do not switch less often than the general population when both
populations are comparable on age, sex and education.
For the general population, premium is more important than content, while the chronically ill and
disabled value content of the insurance package as well. However, quality of care is not important
for either group as a reason for switching.
Conclusion: There is increased mobility in the new system for both the general population and
the chronically ill and disabled. This however is not based on quality of care. If reasons for switching
are unrelated to the quality of care, it is hard to believe that switching influences the quality of care.
As yet there are no signs of barriers to switch insurer for the chronically ill and disabled. This
however could change in the future and it is therefore important to monitor changes.
Dutch healthcare reform: did it result in performance improvement of health plans? A comparison of consumer experiences over time
<p>Abstract</p> <p>Background</p> <p>Many countries have introduced elements of managed competition in their healthcare system with the aim to accomplish more efficient and demand-driven health care. Simultaneously, generating and reporting of comparative healthcare information has become an important quality-improvement instrument. We examined whether the introduction of managed competition in the Dutch healthcare system along with public reporting of quality information was associated with performance improvement in health plans.</p> <p>Methods</p> <p>Experiences of consumers with their health plan were measured in four consecutive years (2005-2008) using the CQI<sup>® </sup>health plan instrument 'Experiences with Healthcare and Health Insurer'. Data were available of 13,819 respondents (response = 45%) of 30 health plans in 2005, of 8,266 respondents (response = 39%) of 32 health plans in 2006, of 8,088 respondents (response = 34%) of 32 health plans in 2007, and of 7,183 respondents (response = 31%) of 32 health plans in 2008. We performed multilevel regression analyses with three levels: respondent, health plan and year of measurement. Per year and per quality aspect, we estimated health plan means while adjusting for consumers' age, education and self-reported health status. We tested for linear and quadratic time effects using chi-squares.</p> <p>Results</p> <p>The overall performance of health plans increased significantly from 2005 to 2008 on four quality aspects. For three other aspects, we found that the overall performance first declined and then increased from 2006 to 2008, but the performance in 2008 was not better than in 2005. The overall performance of health plans did not improve more often for quality aspects that were identified as important areas of improvement in the first year of measurement. On six out of seven aspects, the performance of health plans that scored below average in 2005 increased more than the performance of health plans that scored average and/or above average in that year.</p> <p>Conclusion</p> <p>We found mixed results concerning the effects of managed competition on the performance of health plans. To determine whether managed competition in the healthcare system leads to quality improvement in health plans, it is important to examine whether and for what reasons health plans initiate improvement efforts.</p
Transformations to Symmetry and Homoscedasticity
Transformations to Symmetry and Homoscedasticit