"Internet advertising has been the fastest growing advertising channel in recent years
with paid search ads comprising the bulk of this revenue. We present results from a series
of large-scale field experiments done at eBay that were designed to measure the causal
effectiveness of paid search ads. Because search clicks and purchase intent are correlated,
we show that returns from paid search are a fraction of non-experimental estimates. As an
extreme case, we show that brand-keyword ads have no measurable short-term benefits. For
non-brand keywords we find that new and infrequent users are positively influenced by ads
but that more frequent users whose purchasing behavior is not influenced by ads account for
most of the advertising expenses, resulting in average returns that are negative."
http://faculty.haas.berkeley.edu/stadeli...MA_rev.pdf
Der Artikel ist schon relativ alt, aus 2014. Die Wahrheit darin scheint aber noch nicht durchgedrungen zu sein, nämlich dass personalisierte Werbung gar nicht funktioniert.
Siehe auch :
https://www.handelsblatt.com/finanzen/an...13512.html