Abstract:
:We propose a semiparametric method for estimating ROC surfaces for continuous diagnostic tests based on two test measurements. Such a three-class diagnostic problem based on two test measurements arises naturally from some DNA amplification-related diagnostic scenarios. Simulation results show that our proposed semiparametric ROC surface estimator is more efficient than the nonparametric counterpart and is quite comparable with the parametric counterpart when model assumption of the data is correctly specified for the parametric method. Moreover, when the parametric model assumption is not true, our proposed semiparametric method is superior to both nonparametric and parametric methods. Some discussions and a simulated example along with R programs for implementation of the proposed method are also provided.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Wan S,Zhang Bdoi
10.1002/sim.3625subject
Has Abstractpub_date
2009-08-15 00:00:00pages
2370-83issue
18eissn
0277-6715issn
1097-0258journal_volume
28pub_type
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