Study Suggests the Number-Line Concept Is Not Intuitive

An anonymous reader writes "The Yupno people of New Guinea have provided clues to the origins of the number-line concept, and suggest that the familiar concept of time may be cultural as well. From the article: 'Tape measures. Rulers. Graphs. The gas gauge in your car, and the icon on your favorite digital device showing battery power. The number line and its cousins – notations that map numbers onto space and often represent magnitude – are everywhere. Most adults in industrialized societies are so fluent at using the concept, we hardly think about it. We don't stop to wonder: Is it 'natural'? Is it cultural? Now, challenging a mainstream scholarly position that the number-line concept is innate, a study suggests it is learned."

Re:Ordered sets

[Anonymous Coward]

If you read the article, you'll see that the subjects of the study do understand order, but that they lack the intuition of another property of the number line that you are so accustomed to that you're not aware of it. When asked to place numbers from 1 to 10 in order, control subjects (from the US) produce an arrangement like this:

1...2...3...4...5...6...7...8...9...10

The people of the Yupno Valley tend to do something more like this:

1.2.3.4...................5.6.7.8.9.10

A number line has more than order; it also has equal spacing. That idea seems not to be innate.

Americans don't understand number lines either

[phantomfive]

In the original task, people are shown a line and are asked to place numbers onto the line according to their size, with "1" going on the left endpoint and "10" (or sometimes "100" or "1000") going on the right endpoint.

Go to a class of college students in america, ask them to mark 10, 1 million, and 1 billion on a line, and 99% of them will draw 1 million closer to 1 billion. Usually a lot closer.

I read the article, and it wasn't clear to me what these people have discovered. Maybe I'll have to read the actual study. Or maybe anthropologists are better at understanding primitive cultures than their own.

Re:Valleys and Language

[JoshuaZ]

The Piraha are in South America and they have a language that is lacking many words considered normal in other cultures. http://en.wikipedia.org/wiki/Pirah%C3%A3_language [wikipedia.org]. They give directions primarily in terms of the relation to the river (towards or away from the river or up or down the river) which may be what you are thinking of. There's a highly readable book about the tribe and their language- "Don't Sleep, There Are Snakes" by Daniel Everett, a linguist who spent decades with them. However, there's some degree of question by other scholars about how accurate Everett's description of their language was, and research is ongoing.

Re:Anyone who has ever taught math knows this

[ShanghaiBill]

If your 10 year old doesn't ALREADY understand the number line, you have failed. Hell, if your 6 year old doesn't understand it, you've failed.

Then I guess I failed. My seven year old son is at the top of his 2nd grade class in math. Be he was doing the number line exercise in Khan Academy [khanacademy.org] about two weeks ago, and he needed some help. Once I explained the concept, and gave him a few examples, he "got it", and was able to do the exercises. But it was not intuitive. He needed an explanation.

Re:Anyone who has ever taught math knows this

[Kergan]

Math is logically consistent in itself.

*Cough*

http://en.wikipedia.org/wiki/Hilbert's_second_problem [wikipedia.org]