Talk:2286: 6-Foot Zone

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Ok... 34 feet, in total, but how many hands? (All of which you should wash!) 23:34, 27 March 2020 (UTC)

Well, a typical horse stands 15.2 hands tall. You do the math. Cellocgw (talk) 01:09, 29 March 2020 (UTC)

Love it. Given the extra 1.7 feet for the person, a radius of 20.53 hands. If it were just 6 feet, 18 hands -- brad -- 00:55, 28 March 2020 (UTC)
For a horse of 16 hands (from the USFS document), 130 hands (8x16 'hands' + 2 hands). Or 123 and three loose fingers using Cellocgw's value, with that sounding like it's from actual practical experience. 19:09, 29 March 2020 (UTC)

So Randall is figuring about 1.7 feet diameter for the person. -- 00:40, 28 March 2020 (UTC)

The 190,000 people / mile^2 assumes (I'm guessing) flat ground. Skyscrapers make a difference [citation needed] -- brad -- 00:55, 28 March 2020 (UTC)

Interesting that the population density he gives ignores circle packing. Population should be 174,000. -- coyne -- 04:06, 28 March 2020 (UTC)

Circle packing is unimportant since he's just giving the population of this one circle. He's taking a radius of 6 foot around that person without specifying what he considers to be the radius of the person, but it can be inferred from the numbers:
from area: \sqrt{145/\pi} \approx 6.8,
from circumference: 43/(2\pi) \approx 6.8,
from population density: \sqrt{1/190000/\pi} \cdot 5280 \approx 6.8,
so apparently he considers a person to have a radius of 0.8 ft, or about 0.5 m diameter, which seems reasonable. Zmatt (talk) 05:11, 28 March 2020 (UTC)
For what it's worth, Randall's "6' zone" appears to be an ellipse, not a circle. It appears that Megan is 2.65 feet wide:
  • circumference = 2 × π × 6' + 2 × 2.65' ≅ 42.999'
  • area = π × 62 + 2.65 × 2 × 6 ≅ 144.894 ft2
Scs (talk) 18:14, 20 June 2020 (UTC)
Note that even if you want to know the population of optimally packed people, your number is still wrong since the circles overlap: your circle is supposed to exclude other people, it doesn't exclude other people's circles. Optimally you'd have a triangular lattice of people with a lattice distance of 7.6 ft (assuming we want 6 ft between people and we consider people to be circles of radius 0.8 ft). This yields a population density of 1 person per \tfrac{1}{4}\sqrt{3} \cdot 7.6^2 \text{ ft}^2, which is about 1.1 million people per square mile. Zmatt (talk) 05:24, 28 March 2020 (UTC)
But some people still live in cities. So they are not packed 2-dimensional but sometimes in very high skyscrapers. We need to bringt globes into this calculation instead of circles. --Lupo (talk) 06:40, 30 March 2020 (UTC)

Much as I love thinking about circle packing density in the plane, I think the above explanation is slightly overthinking the issue. The population density figure appears to be using the idea that one person's zone contains one person; 1 person / (145 ft^2) does indeed equal 192,000 people/square mile. So, he's not saying that 'given these constraints, we can pack people at this maximum density'. He's saying 'given this area, and counting it as a tiny sovereignty, we can calculate its population density to be this'. For this reason, I don't think you should say that the 'population density' figure has an error, only that it is calculated in a different sense than you were thinking about. Dextrous Fred (talk) 18:58, 28 March 2020 (UTC)

I agree. My first instinct on what the population density figure means was the same as one used in the comic. 22:29, 28 March 2020 (UTC)

Possibly a play on the fact that horses are measured in hands? --orbitalbuzzsaw--

Page 207 of US Forest Service Equestrian Design Guidebook for Trails, Trailheads, and Campgrounds says minimum corral size is 12x12 feet. I didn't find a more likely sounding Forest Service publication. So I assume the handbook in the comic is a fictional publication. Hamjudo (talk) 13:15, 28 March 2020 (UTC)

Don't look for corrals. Look for how are you supposed to pack the horses for traveling eg. in train or truck/trailer. -- Hkmaly (talk) 00:22, 29 March 2020 (UTC)

Always knew cities were bad for humanity. As are airplanes. Need them both to create a pandemic. Seebert (talk) 18:32, 28 March 2020 (UTC)

Thanks for that explanation! When I saw the title text, I was worried that WHO had increased the recommendation and I'd missed it. TobyBartels (talk) 00:47, 29 March 2020 (UTC)

Cool. I didn't know the US Forestry Service designed horses. These Are Not The Comments You Are Looking For (talk) 06:00, 29 March 2020 (UTC)

Should it be noted that Randall used horses as units of measurement and/or as reference objects before? i.e. 1461 Elektrizikekswerk (talk) 08:52, 30 March 2020 (UTC)

I'm relatively surprised that nobody is discussing the 'real estate' value in these comments. I guess I'm the odd one out. The value of $195k was, to my surprise, very accurate. currently lists that the average real estate price per square foot in Manhattan is $1,371, which, when multiplied by Randall's approximate 145 square feet, gives $198,795. I can't believe the rest of you are putting this much research into horse dimensions. 23:55, 30 March 2020 (UTC)

I'm with you, there should be a comment on that reference to NYC Real Estate. I wasn't too sure about how, exactly, to do the math. The Real Estate market actually has those 145 square feet stacked up, so I was thinking about 145 square feet of _land_, but the zillow numbers are for 145 square feet of _floor_. Since your numbers work out, that probably means Randall was going for that reading. MAP (talk) 03:38, 31 March 2020 (UTC)
But of course, NYC is not only Manhattan; i'm pretty sure that the rest of the city is cheaper.