Ethan Zuckerman published a very interesting review of our paper Personal Web searching in the age of semantic capitalism: Diagnosing the mechanisms of personalization" which we recently published in First Monday. He makes a very problematic point much clearer that we have: the constantly shifting nature of the "object" (that is, the Google search algorithm) in relation to being researched. He speculates how it might be continuously adapting itself in order to optimize our behavior. Here's how he puts it:

I was struck by the apparent discontinuities in how often personalized search results appeared for the three different profiles. In one training session, there’s a sharp spike in personalization between sessions, a test of results where personalization appears three times as often as in other sessions. In another, there are two, smaller spikes, and in the third, a three-session long spike. With no easy way to explain what’s causing these spikes, it’s possible to speculate that Google’s algorithms for personalization are not just opaque and complex, but adaptive and changing. While the authors are experimenting with Google, it’s reasonable to assume that Google is experimenting with them, changing levels of personalization to see whether Google is able to achieve its desired result: clicks on ads.

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Deep in Feuz, Fuller and Stadler’s paper is the sense that there’s something unheimlich about the idea that something as important an influencer as Google being as mercurial as it is. Personalization is disturbing to the extent to which it separates us from the real, true, stable search results, the ur-results Google is withholding from us in the hopes of selling us ads for effectively… but even more disturbing is the idea that there’s no solid ground, no single set of best results Google could deliver, even if it wanted to.