TITLE: Imputating Missing Values in Diary Records of Sun-exposure Study
AUTHORS: A. Szymkowiak, P.A. Philipsen, J. Larsen, L.K. Hansen, E. Thieden, H.C. Wulf
Informatics and Mathematical Modelling, Building 321
Technical University of Denmark, DK-2800 Lyngby, Denmark
Department of Dermatology, Bispebjerg Hospital
University of Copenhagen, Bispebjerg Bakke 23
DK-2400 Copenhagen, Denmark
In a sun-exposure study, questionnaires concerning sun-habits were
collected from 195 subjects. This paper focuses on the general
problem of missing data values which occurs when some, or even all,
the questions have not been answered in a questionnaire. Here only
missing values of low concentration are investigated.
We consider and compare two different models for imputating missing values: the
Gaussian model and the non-parametric $K$-Nearest
To appear in Proc. of NNSP-2001, Falmouth, Massachusetts, Sept. 10-12, 2001.