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Mess Age
Scribble: Perspective drawing

Mess Age

Starting from Comic #148: Scribble: Perspective drawing
Scribble: Perspective drawing
Imagine looking over and down on a short cylinder with equally-spaced verticals, like a round fence with posts as seen here.
I've seen examples of getting the perspective right using vanishing points on the horizon, setting up the elliptical shape. But they don't show something seen in reality, that you'll see fewer verticals in the front than in the back.

This quick sketch shows why. The viewer would see three verticals in front, five in back. In perfect geometry terms, the viewer would always see less than 180° of the circle so for an even number of points they would always see less points in the front.

For an odd number of points there can be more on one half of the circle so it is possible the viewer could see more, like with five points the viewer could see three in front and two in back. The drawing of that is left as an exercise to the reader.

Reader Comments

good point, and what's also often not apparent is that the rear of the oval shape will be distorted the lower to the side that it's viewed. Especially when it's close to the viewer.

But that's a great diagram, showing why the back appears to have more posts.
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Research: No Covid hospitalization uptick
On June 26 there was this tweet purporting to show a possible uptick in COVID-19 hospitalizations after the George Floyd protests, using the graph seen there (which doesn't like to show up here).

Replication remains the hallmark of good science so I went searching. And learned a lot, mostly about spreadsheet charting with LibreOffice. Lots of drawing. For its price, free, it's well worth knowing how to use it. And it beats the pants off of Lotus 1-2-3.

Google puts out their COVID-19 Community Mobility Reports to let you know how much people are moving around. Don't know about the "Covid Hospital Census" but hospitalization numbers from the CDC are available here. Go Display by->Weekly Rate, not cumulative, select age range Overall, download.

For added fun, the CDC goes by numbered MMWR weeks, Morbidity & Mortality Weekly Report, they run Sun to Sat. The X-axis on the graph shows the end dates for the weeks.

The result? Two graphs that look practically the same except for one big difference. No Uptick. Despite the protests, the hospitalization rates according to latest CDC numbers keep going down as they have since the United States started reopening.

So even though there are localized hot spots flaring up, overall we're doing pretty good while opening up again, so far. Good News!

Reader Comments

Your graph certainly suggests that the protests made little or no impact. I'd surmise it's because the protestors are likely to be from a group with a lower risk of being ill if they caught it, or it maybe just doesn't spread that way.
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