On a daily basis we are confronted with a multitude of statistics in the media.
"The 2009 national road toll is running almost six per cent ahead of the number of people killed on our roads last year." AAP, September 14, 2009.
"Mobile wireless broadband subscriber numbers have increased by 51 per cent in the past six months, taking the mobile wireless market share from 20 per cent to 27 per cent, the ABS said." AAP, September 14, 2009.
"Australia's unemployment rate is currently at 5.8 per cent according to the Bureau of Statistics' official survey, despite the loss of 27,100 jobs during August." ABC News, September 17, 2009.
"80 per cent of jobs lost in Western Australia's accommodation sector occurred in regional areas." ABC News, July 15, 2009.
In most cases little or no justification is given for these figures and we are left to make a decision on whether to accept them as facts or pursue our own exploration of their validity. Unfortunately the first exposure one has to an issue can influence their opinion and "mis-facts" may become accepted as "facts".
Responsible journalists are expected to check their sources and substantiate their information. In a time when much of what is reported is in the form of numbers, surely that responsibility extends to the numbers they quote. Is it too much to ask that they be held accountable for misleading the public using poorly quoted statistics?
Tourism in Crisis?
Consider the following article posted on the ABC News website on July 15, 2009. There was no author name attached to the article and no reference to the figures quoted.
Regional WA feels accommodation job losses
ABC News July 15
An Australian Bureau of Statistics survey has found 80 per cent of jobs lost in Western Australia's accommodation sector occurred in regional areas.
The CEO of the Tourism Council of WA, Graham Moss, says tourists could be opting to stay with family and friends rather than spending money on tourist accommodation during the economic downturn.
Mr Moss believes seasonal changes may have led to the job losses.
"I guess for the south-west and also perhaps the mid-west, who are out of season at the moment, there would've been a lot of casual jobs that have been lost," he said.
"But there obviously has been a slight downturn in the tourism industry."
To explore the validity of the article, an investigation of the relevant Australian Bureau of Statistics (ABS) data is necessary . It is often assumed that it is hard to get more reliable data than that presented by the ABS and there is a temptation to simply take the figures and use them. However, no matter where data is sourced from, it is important for the user to be aware of how the data was collected and any inclusions, omissions or assumptions that have been made.
Today, ABS provides a large range of information and statistics to the general public on its website free of charge. Each table comes with explanatory notes to help the user understand the context in which the data was collected, and any assumptions made. To make informed, reliable inferences and to avoid misinterpretation, there is no excuse for not accessing the full data and its accompanying notes.
Although there is no reference to the actual data used in the tourism article above, it appears that the data relates to the ABS release of a quarterly Survey of Tourist Accommodation (STA). The STA is a census of all in-scope  accommodation establishments within Australia. In general, response rates of at least 80% have been achieved. This method of collecting the data suggests that it should be reliable, provided that most employment is in larger establishments. The most current results at the time were released on 14 July 2009 (ABS Cat No. 8635.5.55.001DO001_200903) and refer to the March 2009 quarterly survey. It is natural to assume the article is comparing this release with the previous quarter or some other previous release.
A summary of the results of the STA survey for the March 2009 quarter is given in Table 1, along with the previous four quarters. It is immediately apparent that the article cannot be comparing March 2009 quarterly figures with those from December 2008, as the total number of jobs in WA's regional accommodation sector increased by five between December 2008 and March 2009, while those in Perth decreased by 225.