2011 Census row grows

Statistician-general Pali Lehohla

A former Stats SA deputy ­director-general claims that he and a colleague were axed because they refused to fiddle with the numbers.

Dr Jairo Arrow is at the centre of a row over the accuracy of the R3.4 billion 2011 Census.

However, Statistician-General Pali Lehohla insists the two were removed because they hadn’t done their work properly. Arrow was responsible for the census post-enumeration survey (PES), a second, smaller and independent population survey to establish how many people had been missed in the main count.

He has hit back at his former Stats SA boss in a statement after Lehohla confirmed the behind-the-scenes drama in a City Press report two weeks ago.

At the heart of the dispute is the issue of the census “undercount”.

The undercount estimates how many households were missed in the survey and if the undercount is high, it could mean that the population estimate is unreliable.

Stats SA had targeted a single-digit undercount for the survey, but Arrow said in a statement, when he and a subordinate, Marlize Pistorius, presented Lehohla with preliminary findings, it showed the census undercount was 18.6%, with a population of 41.2 million.

The official population settled on in published census findings was 51.7 million.

Lehohla questioned the pair’s findings and wanted the calculations to be redone.

Arrow said he and Pistorius ­refused because Lehohla’s estimates of the real undercount and total population were “not substantiated on a scientific basis”.

Lehohla told City Press that the initial calculations presented to him did not make sense, and internal correspondence shows that he was seriously considering establishing a commission of inquiry with leading international experts to establish why Arrow and Pistorius’ total count was so low and the undercount so high.

Upon interrogating Pistorius’ findings, Lehohla said he found a significant amount of data gathered during the PES had been omitted from the calculations.

He then established a team, still under Pistorius, to recalculate the PES using all the available data. Pistorius was later removed from the project. Arrow, meanwhile, confirmed he sent an SMS to Planning Minister Trevor Manuel, which City Press has since established read that

Lehohla’s actions were “a massive attempt to obtain different results of the PES than what we have communicated to (Lehohla)”.

Arrow said in his statement that the inclusion of data that had initially been omitted contributed to the final undercount dropping from 18.6% to 14.6%.

He said he and Pistorius “diligently followed established international practice in all aspects of the (PES) and acted throughout with total integrity and professionalism in relation to (the survey), and have always held the best interests of Stats SA as paramount. There were no ‘methodological or computational ­irregularities’.”

He said the disciplinary charges of dereliction of duty and gross incompetence “have not been substantiated with any concrete evidence at all”.

Arrow added that he “refused to plead guilty to any charges levelled against him and had been prepared to proceed with the hearing”.

Following mediation, Arrow had acknowledged that he could have followed internal dispute procedures instead of approaching Manuel and then apologised for not doing so.

City Press twice asked Arrow to further clarify how Lehohla’s reopening of the survey would constitute improper behaviour or a manipulation of the results, but he declined, insisting that his statement be published verbatim. Howard Gabriels, chairperson of Statistics Council SA, said his council had experts from the US, Australia and the United Nations advising them on the methodology following the reopening of the PES, and he was satisfied with the outcome of Census 2011.

- Jeanne van der Merwe