Average Fail - Why Averages Can Be a Terrible Idea in Data Analysis
Short 20 minute session for SQLBits 2026Saturday - 25 Apr 2026 - 14:40 - 15:00 Room 1BTL; DR
Averages can bite you - repeatedly. Come see how and why, and have a laugh and a cry at the same time!
Session Details
What is the easiest way of getting a number controlled for various factors? An average.
Most people stop thinking about the consequences right about here, but the harsh reality is that in many cases, an average is a terrible idea - especially if you don't know the data you're working with in the first place!
Consider what would happen if you start using averages to fill in missing data. or the potential for disasters with trying to average qualitative data expressed as numbers.
I'll spend 20 minutes raking the concept of averages over the coals. Bring marshmallows.
Most people stop thinking about the consequences right about here, but the harsh reality is that in many cases, an average is a terrible idea - especially if you don't know the data you're working with in the first place!
Consider what would happen if you start using averages to fill in missing data. or the potential for disasters with trying to average qualitative data expressed as numbers.
I'll spend 20 minutes raking the concept of averages over the coals. Bring marshmallows.
3 things you'll get out of this session
Why averages are bad
How averages can skew results
What Chicago adds to the story
How averages can skew results
What Chicago adds to the story
Speakers
Alexander Arvidsson's other proposed sessions for 2026
Turning insights into action: The art of data communication - 2026
Fabric FinOps - Cost Optimization for Fabric - 2026
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