aids                  package:boot                  R Documentation

Delay in AIDS Reporting in England and Wales

Description:

     The 'aids' data frame has 570 rows and 6 columns.

     Although all cases of AIDS in England and Wales must be reported
     to the Communicable Disease Surveillance Centre, there is often a
     considerable delay between the time of diagnosis and the time that
     it is reported.  In estimating the prevalence of AIDS, account
     must be taken of the unknown number of cases which have been
     diagnosed but not reported.  The data set here records the
     reported cases of AIDS diagnosed from July 1983 and until the end
     of 1992.   The data are cross-classified by the date of diagnosis
     and the time delay in  the reporting of the cases.

Usage:

     data(aids)

Format:

     This data frame contains the following columns:

     'year' The year of the diagnosis.

     'quarter' The quarter of the year in which diagnosis was made.

     'delay' The time delay (in months) between diagnosis and
          reporting. 0 means that the case was reported within one
          month.  Longer delays are grouped in 3 month intervals and
          the value of 'delay' is the midpoint of the interval
          (therefore a value of '2' indicates that reporting was
          delayed for between 1 and 3  months).

     'dud' An indicator of censoring. These are categories for which
          full information is not yet available and the number recorded
          is a lower bound only.

     'time' The time interval of the diagnosis. That is the number of
          quarters from July 1983 until the end of the quarter in which
          these cases were diagnosed.

     'y' The number of AIDS cases reported.

Source:

     The data were obtained from

     De Angelis, D. and Gilks, W.R. (1994) Estimating acquired immune
     deficiency syndrome accounting for reporting delay. _Journal of
     the Royal Statistical Society, A_, *157*, 31-40.

References:

     Davison, A.C. and Hinkley, D.V. (1997) _Bootstrap Methods and
     Their Application_. Cambridge University Press.

