Hacker News Reader

It's actually "Top 100 [Trending] Searches." They could have been more clear about that.

http://www.google.com/trends/topcharts?date=2013

Yes, it's trending searches, not most popular ones. By the way, non-engineers/non-analytical people usually have trouble differentiating the two. I can't recall how many meetings with product/business people that I have to explain the concepts.

Fairly sure they've filtered out what might constitute "low importance" searched like terms such as 'weather'. Searches for the weather probably remain relatively stable and don't really tell us anything.

I also wondered why the death of Paul Walker was in the video. Surely Lou Reed was more influential, yet his death wasn't mentioned.

I imagine this is a variant of a Latent Dirichlet Allocation[0]. Informally, this will identify words "most associated" with 2013, which is not the same thing as the most searched words in 2013.

Put another way, unless there's a huge spike of interest in the weather in 2013 compared to other years, "weather" won't be included.

[0] https://en.wikipedia.org/wiki/Latent_dirichlet_allocation