How data analysts experience cognitive biases and how to recognise them: Part 5

31 May 2018

Cognitive biases: We all have them and we regularly encounter them in everyday life. But how do data analysts actually experience these biases? And how can you recognise them? In this series we will discuss cognitive biases in the context of analysts. Each blog picks out 3 biases from 20 categories.
In this blog, there are two biases from the “Need To Act Fast” Spectrum: the Sunk Cost effect, the IKEA effect and another bias from the “What Should We Remember?” Spectrum: the Google effect.


Sunk Cost effect

This bias says that if you have invested in something – either in time or money – you don’t want it to have been for nothing. Let’s say you’ve bought tickets to a presentation on the future of the Internet of Things. As it happens, when the evening comes, you really don’t feel like going. But you are still inclined to go anyway because of the Sunk Cost effect – otherwise “the tickets go to waste”. Even though on a financial level it makes no difference whether you go to the lecture, the costs have already been incurred.
Time can work in the same way. You have been working on a MOOC on time series analysis for quite a while but the course is just awful. But you stick with the MOOC to the end anyway, because after all you’ve paid for it and you’re more than half-way through it now. So it’s a waste if you stop now!


IKEA effect

No, this effect isn’t about the parts you have left at the end of your project. The IKEA effect describes how people tend to value things they have made (partly or entirely) themselves more than things that were made by other people. So it isn’t that your churn model is necessarily so much better than the model your colleagues made. And your slides don’t look better and aren’t easier to understand that your colleague’s slides – it’s just that you made them yourself and therefore you value them more.


Google effect

Do you also sometimes realise that you’re looking up exactly how to do anti-join in SQL for the 10th time now? That’s what the Google effect is about: you forget information more quickly because you know you can look whatever it is up online in no time at all, e.g. on Google. Because you know that this source is (almost) always available, you remember information less well. So don’t blame it on your bad memory when you are looking up how CASE and CONVERT work for the 10th time in quick succession – rather, you should be blaming Google. And for that annoying colleague who struggles with the Google effect but somehow struggles to look things up for themselves: LMGTFY!


Cartoon biases series 3-panel 1: churn analysis

Cartoon biases series 3-panel 2: marketing - customers


Also read the other parts:

Part 1: Self-relevance effect, Confirmation bias and the Bias blind spot.

Part 2: Availability heuristic, Contrast effect and Clustering illusion.

Part 3: Essentialism, the Positivity Effect and the Appeal to Probability Fallacy.

Part 4: Curse of Knowledge, the Hindsight Bias and the Hard-Easy Effect.

Part 6: Ambiguity Bias, Appeal to Novelty and False-Consensus Effect.



Do you want to know more about this subject? Please contact us on +31 (0)33 258 28 30 or

Latest news

In 2022, we are going to have a great year of celebration! Many weddings expected

21 February 2022

Plan your calendar free and make sure you have plenty of party clothes in your closet,... read more

Can you escape our “Power BI Escaperoom”?

7 April 2021

In these boring lockdown-times we are all desperately looking for ways to still interact with our... read more

Building a book recommender from scratch

1 April 2021

Almost every day we go online we encounter recommender systems; if you are listening to your... read more

Subscribe to our newsletter

Never miss anything in the field of advanced analytics, data science and its application within organizations!