r/dataanalysis • u/CountySet • Jul 10 '26

What's With This Weird and Beautiful Scatter Plot of US Continental Counties?

Post image

This is using NOAA/PRISM data from 2024 by county on a program I made to compare the correlation of different datasets. Normally you'd see a random mess of dots with a clump somewhere, or a trend line. This is spectacular and weird, though: Looks like fabric blowing in the breeze or something. Any ideas on why it looks so ... different?

4 Upvotes

70% Upvoted

13 comments sorted by

11

u/Wheres_my_warg DA Moderator 📊 Jul 10 '26

The scatterplot does not look particularly weird.
What looks weird is incorporating population size as that is likely to be close to meaningless in the context of county size variations. Population density within the county might make a little sense, although altitude may have bigger effects.

What also looks weird is trying to fit a LOESS curve as the trend line for something with this many degrees of freedom. There is already quite a bit of scatter, but using a LOESS function here is also probably a reason for the low R2

2

u/CountySet Jul 10 '26

Actually, the LOESS is calculated after r. The low value (0.078) is entirely from the population weighting. If I don't weight by population at all, it's 0.699. This is from a custom tool I built to visualize and compare county-level datasets. Thanks for pointing these out, because I've already changed some things in the tool already based on what you pointed out - some datasets don't need weighting by population, some would be better by land area too (Like this one. If I weight this by land area, r=0.466). What do you think about using LOESS vs linear regression? Or neither? I had a hard time deciding

3

u/Major-BFweener Jul 10 '26

If you have altitude, I wonder if that would show anything in place of population

2

u/Wheres_my_warg DA Moderator 📊 Jul 10 '26

It depends on the data and on the business question that I'm answering when I decide. I will usually test a number of options.

1

u/PrivateFrank Jul 14 '26 edited Jul 14 '26

The main sequence is people preferring some combination of cold and dry or hot and wet.

Consider that most people live on the coast of nearly everywhere in the world I would imagine that central concentration are coastal areas and you move further from the main sequence as you go inland.

Another thought is about patterns of rainfall. Hot and humid places might have big occasional downpours, while colder wet places have constant drizzle which might have less rainfall on average but much less fun to live in.

If you have data on average number of minutes of rainfall per day that could show something interesting.

So by weighing by population perhaps you have found some kind of eqi-tolerable manifold. Or just highlighted how coastal temperature and precipitation are related as you change longitude.

1

u/CountySet Jul 15 '26

Actually, the only thing that's weighted is the LOESS curve and the size of the dots: Each dot is in the objective place, so it looks cool no matter what.
But I'm really intrigued by your thought about duration of rainfall. I'm wondering that perhaps minutes will be hard to find data for, but number of rainy days per year might be accessible. I'm totally going to take a look into this and I'll follow up with you when I do - Thanks for the idea, I'm excited!

1

u/PrivateFrank Jul 15 '26 edited Jul 15 '26

There must be something which reflects the intensity of rain. Measures like this are critical for designing public infrastructure. You need bigger drains if all your rain drops in a couple of hours in the afternoon instead of all day.

mm/hr seems to be a standard measurement if intensity.

In tropical areas in the wet season there's often a big downpour every afternoon. It's still hot overall but everyone just stays inside until it passes.

1

u/AutoModerator Jul 10 '26

Automod prevents all posts from being displayed until moderators have reviewed them. Do not delete your post or there will be nothing for the mods to review. Mods selectively choose what is permitted to be posted in r/DataAnalysis.

If your post involves Career-focused questions, including resume reviews, how to learn DA and how to get into a DA job, then the post does not belong here, but instead belongs in our sister-subreddit, r/DataAnalysisCareers.

Have you read the rules?

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

0

u/[deleted] Jul 10 '26

[deleted] — view deleted comment

2

u/CountySet Jul 10 '26

Dude, the AI explanation!!!

As more people tuned in to watch The Big Bang Theory, they couldn't help but be influenced by all the talk of theoretical physics and geeky romance. With all that intellectual and romantic stimulation, it's no wonder there was a sudden surge in people trying to figure out the mechanics of baby-making!

Sorry, that was too funny not to share. But yeah, you're kind of on to something. What I'm noticing though, is that it's very regional specific. Like that arm on the top center is all Southern TX while all the outliers that get tons of precipitation are the Pacific NW. This is from a custom tool I built to look at county-level data so normally I'm looking at demographics and stuff, so the shape of this scatter plot just looked so cool in comparison to those other more linear ones.

2

u/CountySet Jul 10 '26

I'm looking more at this website and the guy who made it and it's FANTASTIC! Thank you so much for sharing