What even is this?

• What: This is a place where I share practical psychometrics, measurement, and applied statistics, in plain language, with code and examples when it helps.
• Why: Because “numbers” are not the goal. Better decisions are. I care about validity, fairness, and being honest about what data can and cannot support.
• To Whom: If you’re into assessment, ed tech, research methods, or you’ve ever looked at a test score and thought “wait, what does this really mean,” you’re in the right place.

What do you plan on posting here?

I’ll post a mix of:

• Psychometrics topics (IRT, DIF, reliability, validity evidence, model checking).
• Applied stats and modeling (GLMs, Bayesian ideas, simulations, and the occasional deep dive).
• Work notes and tutorials, especially the stuff that usually lives in messy notebooks.
• Career and learning reflections, because grad school and real projects both teach you the hard way sometimes.

I’m also going to keep this practical. If a method is “cool” but not useful, I’ll say so. If it’s useful but easy to misuse, I’ll say that too.

What is psychometrics?

Psychometrics is the science of measurement for things you can’t directly “weigh” on a scale, like ability, achievement, depression symptoms, attitudes, and other latent constructs. It’s where we build and evaluate tests, surveys, and scoring models so the numbers we produce are interpretable, defensible, and as fair as we can make them.

In real life, this shows up everywhere: school testing, licensure exams, employee assessments, health questionnaires, and research instruments.

How I work

My default approach is simple:

• Start with the construct and the use case.
• Check items and data quality before trusting any model.
• Prefer transparent diagnostics over “trust me” fit indices.
• Always think about fairness and consequences, not just p-values.

Where to find me

If you want to connect or follow along outside the blog:

• GitHub: https://github.com/fatiihozkann
• LinkedIn: https://www.linkedin.com/in/fatih-ozkan-a5b602158/
• Instagram: https://www.instagram.com/fatiih.ozkann

Conclusion

Thanks for stopping by. I’m glad you’re here. I’ll keep building this into a place that’s useful, readable, and grounded in real work, not just theory-for-the-sake-of-theory.

- Fatih