What's a learning curve and why is steep not h

Question

• What exactly is a learning curve?
• And why is it wrong to use the term "steep learning curve" for something which has high entry barriers and takes quite some time to get into?

As to the why-ness of this question:

• The terms are used often and inconsistently on Stack Overflow
• I myself have been confused by it
• Mostly the newbies are confronted with these terms when they for example ask questions like "what's the best php development framework"

Answer 1

There are a few possible interpretation of "learning curve", but a fairly natural one would be "time elapsed" on the X axis and "knowledge gained" on the Y axis. A steep curve, in that mapping, would imply that you gain a lot of knowledge, fast.

The only interpretation I can think of where "steep" is the same as "hard" is where you map "knowledge gained" on the X axis and "effort expended" on the Y axis and that is not a very natural mapping.

Answer 2

It's a battle of intuitiveness. On one hand, you've got "steep=hard to climb" association, on the other hand you have "time on the horizontal axis" convention (but "proficiency on the horizontal axis" isn't "wrong", just "less popular"). So, IMHO it's not a matter of "right" vs "wrong" but rather "intuitive" vs "more intuitive".

I think that "steep=hard to climb" will win, because it appeals to anyone who at any point in their life has climbed a stair, as opposed to the x-y curve which even people trained in mathematics sometimes mix up.

Answer 3

(from unix.rulez.org/~calver)

_{(source: rulez.org)}

This (very unserious) diagram subscribes to the steep == "hard to climb" interpretation, for anyone keeping score. Emacs. So true. ;-)

Answer 4

from Widipedia:

The term learning curve refers to the graphical relation between the amount of learning and the time it takes to learn.

The term "steep learning curve" is often wrongly used for things which need some time to wrap ones mind around. Also here on Stack Overflow I've seen it used wrongly many times and hence this Question and my own answer to it.

In fact a steep learning curve is given, when it is relatively easy to start of with a new skill/technique/...

it means that the relationship between "learning progress (y)" and "time invested (x)" is greater than 1.

Answer 5

See wikipedia.

"steep learning curve" is a buzz-phrase that doesn't have any actual meaning. It used to mean that you'd make quick progress. "Over time, the misapprehension has emerged that a "steep" learning curve means that something requires a great deal of effort to learn..."

Conclusion: people who use the phrase don't know that it's unclear. You should get details from them on what specific things are hard to learn and get past the buzz-phrases and platitudes.

Answer 6

A "learning curve" originally had total elapsed time [or total cumulative units manufactured/learned] on the X axis and the time required to produce/learn a single unit on the y axis. Your first unit always takes more time than the 100th or 1,000th. The "steepness" of the curve depends on how fast you get good at producing/learning a thing. Learn quickly and you have a "steep" curve; slowly and you have a flat curve.

I agree that the uninformed have morphed the original meaning of the term, but to be accurate steep is easy. People get upset because those of us who paid attention to using language correctly in school rarely get to take part in this type of evolution.