Professor Colin Richards, a former primary school teacher and a former HMI, writes:
“Pisa’s latest findings and rankings are published tomorrow. In the participating countries that have received advanced notice, civil servants and ministers will be picking over the findings to find those that support their already-established ideological positions and to prepare their ammunition for the media.
Because such positions are capable of elastic interpretation and because Pisa’s findings are so numerous, there is bound to be apparent “matches” somewhere in the myriad of data. Those precious matches will be seized on and highlighted in order to achieve a predetermined result or stance – cherry-picking on an international scale.
John Bangs’ opinion piece (“Pisa contains powerful arguments for those fighting to prevent the fragmentation of England’s educational system”) is a classic case. In reflecting on past Pisa findings, he highlights four general policy conclusions with which he concurs and a specific “insight” over climate change with which he agrees. He is engaging in a process for which he roundly (and rightly) criticises politicians, but then as a former union man he is an educational politician.
I happen to support both his four conclusions and the “insight” he cites, but not on the basis of a Pisa methodology that is increasingly under scrutiny and criticism, as illustrated by contributors to recent TES articles and the Radio 4 programme Pisa Global Tables Tested. In addition to deficiencies in the statistical modelling used, there are major issues over cultural bias, over contested values and over limitations of coverage.
According to Wikipedia (like Pisa an apparently authoritative "source"), “the cherry is the fruit of many plants of the genus Prunus and is a fleshy drupe “. The Pisa findings trumpeted tomorrow and for the rest of the week will contain many “cherries” of different ideological flavours, some of which will be used to “prune” ideologically unwanted developments.
In view of Pisa’s limitations, any policy-maker or pundit making too much of his/her selected “cherries” could well be seen as a “drupe” without the 'r'."