Comment Re:IBM (Score 1) 99
It's poorly worded above, but perhaps a better way to say it is that the time-dependent churn in a particular model is negligible (to a statistical irrelevance) if you can get enough data quickly enough. Effectively, once your data stream outpaces the time-dependent effects, those effects may no longer be relevant variables in your calculations.
For example, I'd expect that Google can collect enough data in an hour to determine if a UI improvement is helpful, or if a particular change to PageRank results in more accurate results. Because Google has such a high volume of data collection all of the time, a very short sampling duration all but eliminates the variation due to the time of day, day of the week, or season of the year.
I'm not suggesting that a Big Data solution is somehow magically independent of time. Rather, what I'm saying is that the "store first, ask questions later" approach that is central to Big Data lends itself readily to collecting useful samples quickly enough that delta-t is negligible.