Quarterly Labour Force Survey 2010, Quarter 2

Version 2.0 of the QLFS 2010 Q2 was downloaded from the Statistics South Africa (Stats SA) website by DataFirst in January 2012. This version differs in a number of ways from a version obtained by DataFirst (from Stats SA) at some undeteremined time prior.

The first of the observable differences between old and new versions is the way in which observations that fit into "unspecified", "not applicable" or "missing" type categories are coded for certain variables. For example, in the older version of the QLFS 2010 Q1 the "Occup" variable is coded 88, with the associated label "Not applicable", for 65,445 observations. In the newer version this category of responses is assigned the code 0 and is not labelled (as it was in the previous version) for the same 65,445 observations. This recoding process has been applied to a large number of categorical variables in the datafile. A few other categorical variables have been recoded in a similar vein but as different (non-zero) values. For example, values of 888 for "Q4212TOTALHRS" have been redefined as having the value 88.

Second, a number of extra variables were introduced in the later version. It is unclear why these are not present in the older version of the datafile as they are detailed in metadata that was released at the same time as the original data:

1. "Metro_code" - Metropolitan area code (e.g. Cape Town, eThekwini, Johannesburg, etc.)
2. "Status_Exp" - Expanded unemployment status.
3. "Stratum" - 6 digit number representing stratum formed during master sample 2006 where digit 1 represents province, based on 2005 provincial boundaries, digits 2-3 represent the metro/non-metro area and digit 4 confers geography type.

Third, there are substantive differences between versions for “Geo_type” variable values. In total, there are 88 differences between versions for the “Geo_type” variable. These differences can be summarised as follows:

· 7 observations that were previously coded as “1” are now coded as “2”
· 3 observations that were previously coded as “0” are now coded as “1”
· 78 observations that were previously coded as “0” are now coded as “2”

The reason for these changes is unclear.

Finally, the two versions have different weights. To DataFirst's knowledge, the weighting changes are not clearly documented by Stats SA. The most likely explanation for the difference between the two sets of weights is that the newer version is calibrated to an updated set of mid-year population estimates. Users are advised to remain aware of these slight calibration differences when employing weights.

A new version of this dataset was released in 2014. The new version (our version 2.1) was reweighted to reflect the new population benchmarks from Census 2011.

This version, version 2.1, includes the new weights for the QLFS 2008-2013 series.