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Suspicious discontinuities (2020)

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Re: Suspicious discontinuities (2020)

#81

Post by hollerith »

neilv wrote: post #77

I was all excited when I saw on Zillow a decent new apartment complex in town with rents that were actually reasonable... until, after hours of studying photos and floorplans and neighborhood, I noticed a statement on Zillow, near the bottom of the scroll, in one of the tabs in right column, that the building is subsidized, and there's a permissible income range. While some of us could qualify while on early startup…

>I know I wouldn't feel good about having to move from a nice building because the startup was doing OK.

Subsidized apartment buildings in the US don't make you move out if your income goes up: they just take away your subsidy, i.e., your rent goes up to what HUD calls the apartment's "contract rent". Then HUD (statistically speaking) directs the money they used to use to subsidize your rent to building more subsidized housing. HUD wants successful people living in HUD-subsidized buildings, at least the ones with children in them, to serve as role models.

Re: Suspicious discontinuities (2020)

#82

Post by noqc »

The author of the marathon paper explains the phenomenon he is observing, and then goes on to "reject that explanation" without attempting to do anything to control for it.

>For example, the 2013 Chicago Marathon provided pace teams for 3:00, 3:05, 3:10, 3:15, 3:20, 3:25, 3:30, 3:35, 3:40, 3:45, 3:50, 3:55, 4:00, 4:10, 4:25, 4:30, 4:40, 4:55, 5:00, 5:10, 5:25, and 5:45.T he institution of pace teams then could provide an alternative explanation for the bunching we observe at round numbers.

It would be easy to do, even. Restrict to marathons where the pace team spectrum is known to be of a specific type and see if the other spikes disappear. The author certainly has the data to do this, and isn't. That is suspicious.

Re: Suspicious discontinuities (2020)

#84

Post by deathanatos »

hammock wrote: post #23
JohnMakin wrote: post #18

I went to school at a relatively late age and started in community college. The school/state had a policy where any independent income earners making less than 35,000/year would not pay tuition. A single dollar over that would require paying full tuition of ~$60/unit or about $750 a semester. One year I worked a little more overtime during the holidays than usual and realized with a week to go in the year that I'd go…

An instructive image of the welfare trap: https://en.wikipedia.org/wiki/File:Welfare_trap.png People making $30K on welfare would need to make $81K at an actual job to have the same income after tax. More info: https://en.wikipedia.org/wiki/Welfare_trap

That graph needs [citation]s. The source it cites does not mention how they obtained the figures for childcare, and a questioner in the comments asks for, and does not receive, a source for that information. The source article itself doesn't even seem to be the source, it links to yet another article. That article also doesn't seem to be the source, the source appears to be … a politician.

The childcare part — the largest and most problematic benefits cliff in the graph — appears to be specific to PA. But PA doesn't offer a monetary childcare benefit: one would have to be arguing that this is the specific dollar amount that the care is worth … which … IDK. I'd like to at least see that argument. But the vesting cliff, as depicted, doesn't line up with any of PA's cutoffs, either.

So, this graph smells of statistical lies.

Re: Suspicious discontinuities (2020)

#85

Post by jancsika »

> One reason people were looking for ways to lose money was that, in the U.S., there's a hard income cutoff for a health insurance subsidy at $48,560 for individuals (higher for larger households; $100,400 for a family of four). There are a number of factors that can cause the details to vary (age, location, household size, type of plan), but across all circumstances, it wouldn't have been uncommon for an individual going from one side of the cut-off to the other to have their health insurance cost increase by roughly $7200/yr. That means if an individual buying ACA insurance was going to earn $55k, they'd be better off reducing their income by $6440 and getting under the $48,560 subsidy ceiling than they are earning $55k.

Except that in real life there is no /dev/null that you can immediately pipe in exactly $6440 to hit your target.

You have to spend your time in order to achieve this reduction in AGI.

And discontinuities being discontinuous means that the number of people who have the necessary training/experience to confidently achieve this in, say, three hours, is probably in the same ballpark as people who can successfully set up encrypted email in the same amount of time.

For everyone else, it's going to take at least a week's worth of time to plan, double check, execute, triple check, etc. (And realistically double that, or more.)

At 55K, you've already spent that savings in the value of the time you gave up to get the savings.

People often make fun of free software developers for failing to properly value their own time. But at least that's not their domain of expertise. A financial hobbyist spending $2 of their time to save $1 is professional grade irony.

Edit: clarification

Re: Suspicious discontinuities (2020)

#87

Post by chatmasta »

nominatronic wrote: post #36

A similar fun example is the distribution of Elo ratings on a chess site, e.g. here's the weekly distribution on Lichess for Bullet games (less than 3 minutes): https://lichess.org/stat/rating/distribution/bullet It's easy to understand why this happens: - Player ratings will fluctuate by small amounts as they win and lose individual games. - People are happy to stop playing when their rating is at e.g. 1503, but if…

> At any given time, most accounts are not playing, so the distribution shows a bias towards values just over a 100 Elo threshold

FYI, that graph only includes players who were active (played a game) this week.

Re: Suspicious discontinuities (2020)

#88

Post by euroderf »

armchairhacker wrote: post #52

At least in the government, there should be a law that any hypothetical scenario where someone making more money before government taxes/incentives would cause them to earn less after, must be quickly resolved by replacing hard cutoffs with gradients. No benefits should apply 100% for anyone making under a certain amount and 0% for anyone making over. Instead there should be a range they slowly decrease, so that if y…

Replace one number (the cutoff) with two (the start and end of sliding part).

Re: Suspicious discontinuities (2020)

#89

Post by mrandish »

Coding hard cut-offs like this into legislation, regulation or policies seems crazy almost to the point of negligence, incompetence or malice. Especially when it's so obvious such cliffs will incentivize behavior certain to cause negative or perverse outcomes. It's even more incomprehensible when implementing graduated thresholds is so well understood.

A related common failure mode is baking in fixed, absolute thresholds for dynamic domains sure to evolve instead of linking thresholds to dynamic metrics (such as inflation, cost of living, etc).

Re: Suspicious discontinuities (2020)

#90

Post by nominatronic »

chatmasta wrote: post #87
nominatronic wrote: post #36

A similar fun example is the distribution of Elo ratings on a chess site, e.g. here's the weekly distribution on Lichess for Bullet games (less than 3 minutes): https://lichess.org/stat/rating/distribution/bullet It's easy to understand why this happens: - Player ratings will fluctuate by small amounts as they win and lose individual games. - People are happy to stop playing when their rating is at e.g. 1503, but if…

> At any given time, most accounts are not playing, so the distribution shows a bias towards values just over a 100 Elo threshold FYI, that graph only includes players who were active (played a game) this week.

Yes, but that doesn't change the fact that out of all the accounts included, most of them won't be actively playing games right now.
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