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

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.