Because those sites use ad code from AliMom, which is owned by Alibaba, as is Taobao.

As for the principle of this thing itself, it is to identify and record the user's search behavior through cookies, and then summarize and match it in the background through data analysis and machine learning.Amazon has been using this way to recommend products to you for a long time.

That said, this is actually a manifestation of the very popular term "big data".

Expanded:

Big data has a wide range of applications in modern life, with the Los Angeles Police Department and the University of California collaborating to use it to predict crime. Google Flu Trends (GoogleFluTrends) uses search terms to predict the spread of bird flu.

Statistician Nate Silver (Nate Silver) is one of the first to use big data to predict the spread of avian flu. Silver (NateSilver) using big data to predict the 2012 U.S. election results. The Massachusetts Institute of Technology uses cell phone location data and traffic data to create city plans.

Macy's real-time pricing mechanism. Based on demand and inventory, the company's SAS-based system adjusts prices for up to 73 million items in real time.

The healthcare industry has long encountered the challenge of massive amounts of data and unstructured data, and in recent years many countries have been actively promoting the development of healthcare informatization, which has allowed many healthcare organizations to have the funds to do big data analysis.

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