All Things Data Science

Those of you who already have attended a meetup of the Brussels Data Science Community know that, besides excellent talks, those meetups are fun because of the traditional drinks afterwards. So after the last meetup we were on our way to a bar on the campus of the University of Brussels and I had this chat with @KrisPeeters from Dataminded. Now if you are expecting wild stories about beer and loose women (or loose men for that matter), I'm afraid I'll have to disappoint you. Instead we discussed ... sampling. Kris was questioning whether typical sample sizes market research companies work with (say in the hundreds or a few thousand at the max) still matter these days, given that we have other sources that give us much larger quantities of data. I told him everything depends on the (business) question the client has. To start with we can look at history to answer this question. In 1936 the Literary Digest poll had a sample size in the millions. But, obviously, that sample wa...

Currently there is a debate in Belgium about the construction of Uplace, a huge shopping mall on the outskirts of Brussels. A marketing professor of the Vlerick School, Gino Van Ossel, did a survey which showed that, contrary to popular believe, quite a big group was actually in favor rather than opposing the plans. So far so good, but the professor's methodology was questioned in the media. The arguments used against the survey findings were not very strong, I believe, and I will not discuss them here. However, a part of the reasoning used by Gino Van Ossel looked rather odd to me and made me think about a more general problem that I would like to discuss here. Those of you who understand Dutch can find all the details on www.marketingblog.vlerick.com . In short, he found that in a sample of 654, representing the total Belgium, 33% was in favor, while in the region where the shopping mall would located, with a sample of 182, 46% were in favor. This was against the popular believ...