The science behind predictability: why certain data can (really) help you choose the right person
Can we really predict a candidate's success at work?
This is the big question, not only in HR, but in all areas where decisions are made about human beings. When we talk about predictability, especially in the world of psychometric assessment, we’re not talking about crystal balls or managerial intuition. We’re talking about data, science, and validated and tested models.
At TalenTest, we like to go beyond simple fit or interview impressions. We rely on science to offer tools that truly predict behavior, performance, and adaptability. And that’s possible thanks to what we call psychometric predictability.
This topic resonates particularly with Sylvain Brodeur, a well-known figure in the HR world who stands out for his human, nuanced, and strategic approach. His perspective on predictability is invaluable: he reminds us that behind every piece of data is a person, a team, an impact. For him, the challenge is not to predict for the sake of predicting, but to do so in order to better support, better guide, and better decide.
In this article, Sylvain provides an accessible (yet rigorous) overview of the science behind predictability. Why is it important? How does it work? And above all: how does it actually change your HR decisions?
1. What is predictability?
In simple terms, predictability refers to the ability of a tool or indicator to predict a future outcome. In HR, this outcome could be job performance, job stability, ability to collaborate, or even job satisfaction.
Concrete example:
If a test measures logical ability and people who score high perform better in analytical positions, we can say that this test is predictive of performance in this type of role.
But be careful:
For a tool to be truly predictive, it is not enough for it to “seem” relevant. It must have been scientifically validated, i.e., studies must have demonstrated that there is a significant correlation between the test result and the target criterion (e.g., performance, commitment, long-term success).
2. Predictability is a matter of correlation... but not only that
In scientific jargon, we often talk about predictive validity. It is measured using correlation coefficients, generally between 0 and 1. The higher the correlation, the more predictive the tool.
Here are some benchmarks:
- 0.1 to 0.3: weak correlation
- 0.3 to 0.5:moderate correlation
- 0.5 and above:strong correlation (and very rare in the humanities)
But the science of predictability is not limited to a simple equation. It takes into account several contextual factors, such as:
- The nature of the position
- The work environment
- The skills sought
- Potential biases
And this is where good psychometric tests make all the difference: they are designed to isolate relevant variables, limit bias, and adapt to the professional context.
3. What research (really) tells us about the best predictors of performance
Several studies have compared the selection methods used in companies to identify those that best predict performance.
Here’s what science tells us:
Conclusion? Well-designed tests—and especially well-used ones—have strong predictive power. And when they are combined (e.g., aptitude test + personality test + structured interview), the predictability becomes even stronger.
4. Why it's essential in 2025 (and beyond)
In a tight labor market, where retention, diversity, and performance issues are more critical than ever, relying on predictive tools is no longer a luxury—it’s a necessity.
Reliable predictions enable you to:
- Hire better from the start (and therefore reduce turnover)
- Build more complementary teams
- Support talent development
- Make decisions more objectively, thereby reducing unconscious bias
And that has a direct impact on employer branding, profitability, and the work environment.
5.The common mistake: confusing intuition with prediction
Some managers still believe that their instincts are the best tool for evaluation. However, research is clear: intuition alone is a very poor predictor of performance.
Why? Because it is colored by:
- Cognitive biases (halo effect, similarity bias, etc.)
- Emotions
- Past experiences… sometimes irrelevant ones
It’s not that intuition is useless. It can guide or raise doubts. But to make an informed decision, it must be validated with objective and predictive data.
6. How TalenTest puts predictability at the service of HR
At TalenTest, all our tests are designed to offer a high level of predictability without complicating the process. How?
- By relying on validated psychometric models
- By testing the reliability and validity of each tool
- By providing reports that are easy to interpret (even for non-psychologists!)
- By allowing customization according to the type of position or organization
In other words: we give you the right indicators, at the right time, to make the right decisions.
Conclusion: predict, yes... but responsibly
Predictability is not a magic formula, but a powerful tool. Used correctly, it allows us to better understand, better anticipate, and ultimately… better support.
In a constantly changing world of work, it becomes a compass. Not to tell us exactly where to go, but to keep us from going around in circles.
At TalenTest, we believe in a human science that is accessible and useful. To inform judgment, not replace it.
What if we really used the power of data… to build smarter, more inclusive, and more effective environments?
Do you have questions or want to chat with one of our experts?
Our specialists are here to help you understand how the science behind predictability can be applied to your HR challenges. Whether you want to optimize your selection processes, equip your managers, or just explore best practices in psychometric assessment, we’ll take the time to talk it over with you.