The relationship between evidence and theory

Summary

• Evidence tells us that a particular approach is effective in improving learning.
• Learning theory explains why this and other methods are effective (or ineffective)

Reliable evidence

The process of getting reliable evidence using the empirical method is well documented:

• Make an observation or measurement
• Create a hypothesis which might explain the evidence
• Carry out an experiment or take further measurement to test the hypothesis
• If wrong, reject the hypothesis and try a new one
• If it looks promising, get others to repeat the test etc.

For the natural science, such as physics or engineering, only a few measurements etc are needed because we can do a ‘control the variables’ type experiment where we only change one thing.

For all other areas, like biology, medicine, education, agriculture etc (a) we cannot control all the variables and (b) individual people, plants etc are different.  For reliable evidence in these areas we need to rely on two things:  

• a large data set (we will get average results)
• some sort of comparison or ‘control’ group to compare

Using this method we can, for example, conclude that ‘spaced repetition’ by students greatly increases their long-term memory of that topic.

The need for theory

The limitation of this evidence is that it only tells us, for example, that spaced repetition is effective, it does not tell you why.  For this you need an underlying theory or model. Apart from education, almost all other professions have such an underlying model.  Midwives, for example, learn basic anatomy etc. related to childbirth.

These theories or models are developed from the reliable evidence is much the same way as described above.

• Look at a range of reliable evidence, for example, 6 classroom methods which have been shown to be effective, and see if we can see an underlying pattern or set of principles which could explain many of them.
• Formulate a hypothesis.
• Test it
• Etc.

Benefits of a theory of Learning

The theory now creates the potential to suggest other methods which may work well or help explain that a method cannot work.  Nearly all other professions use theory this way.

Without a shared learning theory teaching will continue to be dogged with fads, gurus, authors, school leaders, minsters etc, all offering ‘solutions’ based on little more that ‘this feels right’.

Draft Feb 2025