Hacker News Reader

Comment by lighttower | Hacker News Reader

I've always wanted a system that accounts for adjacent physical locations appearing to be far apart upon truncation because they happen to sit on opposite sides of the imaginary dividing line. E.g. 39.99 deg North looks very far from 40.00 deg North upon truncation

View on HN

I made this but for prices: I felt like I was subconsciously biased towards products priced just below some boundary. When looking at products, you don't necessarily come across them in order, and the prices are not always round (not just decimally round but I'd also say that 501 bucks is not round). Take the series 931, 900, 942, 878: at a glance (without carefully comparing them) I find it hard to know the relative differences. To solve this, I made this which calculates the relative difference on the scale of 10 to 20: http://lucb1e.com/rp/js/scale.htm

For coordinates, if you have point A at 39.99, point B at 40.00, and point C at 41.00, then this tool will show you that the relative distances are 10, 10.1 and 20. There is a huge gap between B and C, relative to between A and B.

I must say that I was surprised to see that it places B so low (only .1 from the base value), so my subconscious bias already shows!

Out of curiousity, how would you solve that? Seems unavoidable to me.

You would need to use two simultaneous coordinate systems. It could be long lat p and long lat with an offset. If the offset version does not change as many digits as the standard then use that one. station curious and so much for machines, where the calculation is cheap. But it's for when you are trying to figure out if someone is next to you on a map or not. All of the coordinate systems that are grid-based including UTM have this problem.

Reply on news.ycombinator.com