Today Cary Roseth talked about the fundamental tension of research: what we want to know vs. what we can know. That’s right, we were yanked out of our ideal, “head in the clouds” world back to reality. It was a great foundation to think about how studies are structured and how they are a representation of this fundamental tension. Take a look at these examples:
Want to Know
|Measurement||True value||Measurement value|
|Construct||Conceptual definition||Operational definition|
When you think about research from this perspective, you see that validity is capturing the difference between our conceptual and operational concept. In other words, do we measure what we think we are going to measure? Reliability is another way to look at the tension as it looks at the relationship between the true value and the measurement value. It is looking at the consistency of a measure.