(this page is part of my 2011 report on “Open Data: Emerging trends, issues and best practices”. Please follow that link to reach the Introduction and Table of Content, but don’t forget to also check the notes for readers! of the initial report of the same project, “Open Data, Open Society”)

Boris Müller, professor for interface and interaction design at the University of Applied Sciences in Potsda, said in an April 2011 interview: “I think that really a citizen needs to know how visualizations work in order to really evaluate the quality of the data and the quality of the evaluation." As data visualization and analysis becomes more popular easier to use (even as a tool for manipulating the public opinion), it’s important for the public to:

• understand that, before becoming digital, information was coded, stored and used in many ways, through social norms and human interactions more complex than computer ones (cfr the digitization of India land ownership records), therefore making exact, one-to-one equivalence between analog and digital procedures hard or impossible in many cases

• think critically about where data comes from

• remember to always follow the development of data-based stories, or accusation.

Here’s an example of why the two last things are important. In April 2011, during a prime time TV talk-show, Italian MP Enrico Letta asked Education Minister Gelmini to justify further cuts to Public Schools declared in the new State budget. Gelmini knew nothing about such cuts to the budget of her own Ministry, so all she could reply at the moment was that Letta’s assertions were inconsistent.

Two days later, two bloggers “proved” that Gelmini was right and Letta’s analysis wrong because he had cited gross figures instead of net ones and ignored that school budget cuts from 2012 onwards were not new at all, but had been already approved in 2008. Right after this debunking, a third blog asserted that everybody was wrong: Letta, Gelmini and also the first two bloggers who, for unknown reasons, had associated to the Education budget alone all the cuts to the whole public sector, and then based all their calculations on a different (and wrong) summary table, not the one used (still wrongly, but for other reasons) by Letta.

As far as we’re concerned, the real issue here is not who was right and why, exactly, all the others made certain mistakes. The actual problem is: how many of the people who saw Gelmini unprepared on TV the day this case started also followed up the story in the next days and found out that things weren’t exactly as they had looked in that talk show, even if Letta had “proved” his case with actual, exact “data”? How many citizens are educated to follow the analysis of some data over time?