Why are there two folders called Weight91 and Weight96 on this CD? 


There are two folders because the May 1999 RTSS data file was weighted twice.  The first time
the 1991 Census was used, and the second time the 1996 Census was used.




Why was the 1999 May RTSS weighted twice?

The Residential Telephone Service Survey (RTSS) is administered to a sub-sample of the
dwellings in the Labour Force Survey (LFS) sample, and therefore its weighting and population
estimates are closely tied to those of the LFS.

In the past the LFS calculated its population totals based on population projections using the
1991 Census.  In January 2000, the Labour Force Survey began calculating its population totals
based on population projections using the 1996 Census.  This resulted in a decrease in the
estimate of the total population.   For RTSS, this resulted in population totals reported in the May
2000 RTSS to be lower than those reported in the August 1999 RTSS.  

Because of this, users were not able to make comparisons between the household counts seen in the May
2000 RTSS and any previous RTSS. Users could, however, continue to compare rates as rates are
robust to changes in totals.

To address this issue, the weights on the May 1999 RTSS microdata file were re-calculated
using the 1996 Census population projections.  This means that users can now compare household
counts in the re-weighted May 1999 RTSS to any household counts in any RTSS collected
after 1999.




When should I use the 1991 weights versus the 1996 weights?

The 1991 weights should be used if:
- you want to compare household counts in the May 1999 RTSS to household counts in the 
August 1999 RTSS, or;
- you want to compare household counts in the May 1999 RTSS to household counts from any 
RTSS that occurred prior to May 1999.

The 1996 weights should be used if:
- you want to compare the May 1999 RTSS with any RTSS that occurred after 1999.

However, if you want to compare rates i.e. the percentage of households without a phone line, 
you can compare May 1999 rates using either weight, with any other RTSS.


Please note:  Both the May 1998 and May 1999 RTSS data files were weighted again using the
1996 Census so that their household counts could be compared with the May 2000 RTSS.