Learning Curves

Recently in class we discussed a case study on the wide-body aircraft industry. In that discussion Dr. Tufte suggested that the evidence supporting the learning curve is really quite flimsy. He said that most of the supporting evidence was gathered during WWII and the decreases in time were the result of lower quality not improved ability. He further stated that the decreases in costs in the wide-body case study came about because the fixed costs were being allocated over more units of production. I’m not sure I buy that. A person does get more proficient at a task with repetition. Dr. Tufte himself I think would admit this, one of the reasons he started one of his blogs was that he “was losing (his) ‘edge’ as a writer.” That would suggest to me a shift backwards along a learning curve. I will admit though that the discussion in class made me question whether or not learning curves are a valid as I had thought.


Cole said...

I thought the discussion of the learning curve was interesting also. I had not really known that it was a theory that was studied and tested in a business environment. I just thought it was a general idea about how we learn.

When we were discussing learning curves, I kept thinking of my 7th grade band teacher when he would say, "Practice does not make perfect! Perfect practice makes perfect!" In other words, just because you do something longer does not neccessarily mean that you do it better.

Ashton said...

Ya I thought that discussion was very interesting. I still believe in the idea of a learning curve. I think you have to be carefull to not classify every improvement as a learning curve. In my mind there is no question that the more you do something the better you get at doing it. I do believe that this only holds true up to a certain point.

Frank said...

I think that there is a learning curve, but just like the cost curve it can have a negative effect if taken to far, however it deals with the human factor more than the cost curve. How repetitive can a firm become without becoming discomplacent in its work. I agree that the average cost curve and the learning curve look the same over the short run, but question the results over the long run.

bryce said...

I also agree that the discussion was very interesting. The example that comes to my mind is changing my flat bike tires as a kid. The first few times it would take me an hour or two to fix the flat tire. By about my 10th time I could change the tire in under 20 minutes. To me, this is the learning curve in action. The discussion will make me take a closer look at the learning curve in the future.

Dr. Tufte said...

-1 on Seth's comment for grammatical problems.

In my defense, I did not say that learning curve effects were the same as economies-of-scale. More precisely, I noted that it is very hard to tell them apart, and most of the serious criticism of learning curve models has been to correct for hidden economies-of-scale effects. And ... the whole point is to get you less focused on that idea.

I do personally believe in learning curve effects, albeit small ones. But, it's my job to be open minded, and if someone who specializes in that area says the evidence is a lot flimsier than we thought, then I pass it on to you.