In 1885, Hermann Ebbinghaus published the results of experiments he performed on himself, trying to understand how long he could remember a list of 3 letter nonsense words of the structure: Consonant-Vowel-Consonant (e.g. BUP, TOV, RUI etc.). The graph, he plotted from this experiment, is known as Ebbinghaus’ Forgetting Curve (see here) . Looking at the curve, mathematicians conclude that forgetting happens exponentially. Here is the formula describing the curve:
R = e-t/s (R = Retention, e = Euler’s constant, t = time elapsed after initial learning, s = strength of memory)
For the rest of us, this means that after a relatively short time, a big portion of the words is already forgotten and only a small proportion is retained over a longer period. Typically, 20 minutes after initial learning of the list of words, only 60% of them are retained. After one hour, the proportion of retained words drops to about 40%. After one day, the proportion is around 30%. After 31 days, the proportion of retained words has dropped to about 20%. These levels can vary with the strength of the memory of the test person.
The Good News
Spaced reviews of the list of words slows down the forgetting curve. With a first review one day after the initial learning, it will take 2 days until the retention level has dropped to the same level reached 1 day after the initial learning. A next review after these 2 days will then extend the time to 3 days after the first review for the retention level to drop to same level as after 1 day of the initial learning. After 5 reviews, the acquired knowledge can be expected to be permanent. E-learning platforms claim providing value in providing these spaced reviews. I also taught this in my graduate courses on sales management, when discussing training, until I was confronted with the revised Bloom’s taxonomy for learning Goals.
The Bad News
This made me understand that fighting the forgetting curve does not make sales training more effective. Bloom’s taxonomy defines 6 cognitive process dimensions. These process dimensions (remember, understand, apply, analyze, evaluate, create) can be understood as sophistication level of the learner; whereas “remember” is the lowest and “create” the highest level (more details here).
I hope you can agree with me that fighting the forgetting curve stabilizes the lowest sophistication level (remember). The British Philosopher Herbert Spencer (1820—1903) is known for his quote: “The great aim of education is not knowledge but actions”. Transposed to Bloom’s taxonomy, this means that education must at least reach level 3 (the first active action word in the taxonomy). This is also the minimum required for learning goals of my graduate courses. For my graduate course “Structuring an International Sales Force”, I have formulated the learning goal as:
Students can apply the ‘Design for Six Sigma’ process to analyze the voice of the customer, evaluate appropriate channels and levels of relationships to create the best suited ‘Go to Market’ strategy.
I posit, that for sales trainings in the field to be successful, learning goals must be as stringent as those for sales education at universities. This is a necessary but not a sufficient condition for a sustainable effect of sales trainings on sellers’ behavior. The second condition for reaching sustainability merits though its own article.