How Search Algorithms Work

You Can't Beat an Algorithm.

Summary: People find new information online three ways:

  1. Digital publications (usually via email notifications to subscribers)

  2. Social media feed posts (shared from within their filter bubble community)

  3. Search Engine feed (results pages) links

Unlike publications, which are curated by humans, both social feeds and search feeds are created by algorithms that maintain the user's filter bubble and leverage the power of AI to select for content that generates engagement, actions and ads.

In this series of activities, students transfer / translate some of the Social Dilemma content about algorithms and business models to Search Engines, which have replaced human librarians as guides to finding answers, for good and for ill.

Fun Pair Activity: Become the Algorithm

Nim is a simple counting game. There are many versions out there - this one is also called "21". There is a discoverable mathematical pattern which means the second player always wins (or any player wins once one makes an error). Our programming students code the game with a "Simple" and "Trainer" mode. In the "Simple" mode, the computer takes random turns; in "Trainer", it wins every time.

Playing this verbally, students figure out how to win. Once one has seen the pattern, they demonstrate it (and give hints) until the partner sees it. Social Media feeds are created by algorithms which, like Nim players who know the secret, will always win*. *Google Search is now hiding or deprecating some categories of disinformation, such as anti-vaccine propaganda. Users who want that content are switching to the Duck Duck Go search engine. If you want to find disinformation, use that.

Essential Question: How do Search Algorithms work?
: Video, Pair Share, Present
Learning Objectives: Students will:

  1. Optional: try random vs algorithmic play.

  2. Play the counting game Nim verbally (21)

  3. Read a flow chart to "train the algorithm"

  4. Experience algorithmic winning.

  5. Help a partner learn how to win.

How Search Works by Matt Cutts (Google)

This is a 15-year-0ld oldie but a goodie (transcript). The animations are very helpful at showing how search algorithms work. Pause for comparison with Social Platform algorithms. Topics:

  1. Searching Google's Index of metadata

  2. The PageRank Algorithm that ranks responses

  3. Advertisements are included in search results

Google's search engine looks a lot different now (see 2007 and 2010). Try "cheetah running speed" and see how much new content Google shows before the actual results.

A Two-Way Street

How Google uses you when you use Google. It's fast, easy and free...but there is a hidden cost. It's great for finding recent articles or buying stuff.

Google's algorithm puts you in a "filter bubble" where you only see certain results, based on things you have clicked on before. That's called "personalization". It's helpful if you're doing what you normally do, but not if you want to see new parts of the world.

That can be particularly problematic when you are doing academic research. You don't see what you're not allowed to see.

Online Activity: Algorithms (Checkology)

This interactive activity can be done full-class with talk pauses and a student response system for making choices - even as simple as hand voting for options. The link is a demo version, so create an account to see all of it. Topics:

  1. Algorithms

  2. Filter Bubbles

  3. Personalization, good and bad

4b FNF: Where To Find Misinfo

Where the Misinfo At?

If you're wondering why you haven't been reading about how vaccines cause Autism, or how Trump actually won the 2020 election, or why Climate Change is a hoax, it's because Google and the major social platforms are suppressing it (thankfully!)

There are darker places where you can easily find it, without having to learn the Dark Web and Tor. The slides at left introduce you to DuckDuckGo, Fox News, and even Truth Social (which needs a mobile phone).

When you find something that strikes you as obvious disinformation, use the form on the last slide to share it with us! Try Google Dorking techniques below.

Google Dorking (a.k.a Google Hacking)

Even if Google is suppressing misinformation, you can get past that by using advanced search techniques and prefix operators that find exactly what you're looking for. "Exposing the Invisible: The Kit ... a collaborative, self-learning resource that makes investigative techniques and tools used by experienced investigators more accessible."

OR: jump directly to their page on Google Dorking where you can learn Boolean searching, as well as special search prefix operators like:

  • inurl:

  • intext:

  • site:

  • feed:

  • language: