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How many flies are in my apartment?

saml98.github.io

41–50 of 158 posts

Re: How many flies are in my apartment?

#41
post #40

In my statistics class we were taught a technique for estimating the number of flies in a barn. You capture a fixed size sample of flies, e.g. 100, and give them each a little white dot on the back, then release them all back in the barn. Leave them to mingle for a while, then capture another fixed number of flies, e.g. 100. If 5 of them have a white dot on them, then you estimate that the 100 flies you captured orig…

If they’re randomly distributed, that makes sense.

Re: How many flies are in my apartment?

#42
post #8

Earlier quoted context omitted.

Open windows for air, but have a finely masked net covering the opening so insects don’t get in.

This is the norm in the south asian country I come from. But ever since I moved to the EU, there have been no nets, then again there are noticeably fewer flies here too.

In Kazakhstan we're using nets because of mosquitos. Flies are not a real issue, they're a nuisance, but not a big deal. Mosquitos on the other hand are real night-killers. Few of them might keep me awake until sunset with their buzzing. Of course preventing flies is a good side effect.

In South Asia, I could imagine that mosquitos are more dangerous because of diseases they transmit.

Re: How many flies are in my apartment?

#43

Earlier quoted context omitted.

Dont the windows have screens? In the US pretty much every window has a permanent screen outside the panel for this purpose...just assumed it was the same in europe

They do not, and it's unfathomable why. One of the first things I did after moving to Berlin was put screens on our major windows. My European friends constantly complain about insects coming in (wasps are a big offender in Berlin - and technically you can't kill them) but for some reason never just put up a screen.

> They do not, and it's unfathomable why.

Our current windows pivot in the middle which makes a fixed screen impossible.

(They do have a "pane inside" mode which would let you put a screen on the outside but we're 3 floors up and it would be a bit tricky, not to mention inconvenient when the temperature drops.)

Re: How many flies are in my apartment?

#44
post #29

Earlier quoted context omitted.

They do not, and it's unfathomable why. One of the first things I did after moving to Berlin was put screens on our major windows. My European friends constantly complain about insects coming in (wasps are a big offender in Berlin - and technically you can't kill them) but for some reason never just put up a screen.

Maybe because screens make the appartment darker?

I mean generally you can't tell from more than 5 feet away so...idk seems like a minor difference

Re: How many flies are in my apartment?

#45
post #33

Earlier quoted context omitted.

Dont the windows have screens? In the US pretty much every window has a permanent screen outside the panel for this purpose...just assumed it was the same in europe

Not in south of Europe unless is a mosquito disco location. One of the main purposes of windows is to see out. The more transparent, the better. Another factor is the light level. If you have a lot of days with rain or low light, like UK or many other places have, nets reduce even more the level of light entering in the house. Lacking of a lot of the dangerous mosquito borne diseases than tropical places have, the co…

Idk I've just never even considered losing light because of the screens, it's so little.

Maybe I'm just used to it.

Also it's not only like a cultural thing, I legally had to put screens in every window of my house before it was able to be occupied. Just an anecdote...

It's weird how we never question things like that.

Re: How many flies are in my apartment?

#46
post #40

In my statistics class we were taught a technique for estimating the number of flies in a barn. You capture a fixed size sample of flies, e.g. 100, and give them each a little white dot on the back, then release them all back in the barn. Leave them to mingle for a while, then capture another fixed number of flies, e.g. 100. If 5 of them have a white dot on them, then you estimate that the 100 flies you captured orig…

Reminds me of how the Allies estimated the production capacity of German tanks during WW2: https://medium.com/dataseries/how-data-science-gave-the-alli...

Re: How many flies are in my apartment?

#47
post #40

In my statistics class we were taught a technique for estimating the number of flies in a barn. You capture a fixed size sample of flies, e.g. 100, and give them each a little white dot on the back, then release them all back in the barn. Leave them to mingle for a while, then capture another fixed number of flies, e.g. 100. If 5 of them have a white dot on them, then you estimate that the 100 flies you captured orig…

Fun idea, but presumably there is a big bias in that some flies will be easier to catch for various reasons. I suppose lots of population studies on birds, cetaceans or whatever have this bias, since you can't just slap a quadrat down and catch everything. In fact with these more advanced animals, perhaps they're harder to observe a second time since they've learned to be wary of humans.

Re: How many flies are in my apartment?

#48
post #8

Earlier quoted context omitted.

This is the norm in the south asian country I come from. But ever since I moved to the EU, there have been no nets, then again there are noticeably fewer flies here too.

Dont the windows have screens? In the US pretty much every window has a permanent screen outside the panel for this purpose...just assumed it was the same in europe

When I lived in Europe there were no screens on the windows.

However, there were also pretty much no bugs; we kept the windows and doors open regularly without an issue - if you tried that were I live now in the US you'd have flies inside making a racket and be eaten alive by mosquitoes.

Re: How many flies are in my apartment?

#49
post #34

All these models ignore how insects actually zero in on a smell. For a fly outside, the source of the smell is the gap in the window. What looks like random direction changes is actually a search pattern for that source.

You are right. Even though it is probably a great exercise to improve your skills as data scientists, I'm afraid that without understanding how the insects actually "work/think", it is nothing more than garbage in, garbage out (GIGO).

Re: How many flies are in my apartment?

#50
post #35
post #34

All these models ignore how insects actually zero in on a smell. For a fly outside, the source of the smell is the gap in the window. What looks like random direction changes is actually a search pattern for that source.

Slightly related: Anemotaxis https://www.youtube.com/watch?v=hIqmIQbQkW8

Thanks, that was actually the screensaver I was thinking of when I wrote my comment :-)

But I don't actually know whether flies do use this pattern.

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