Heat and learning

By Jisung Park, Joshua Goodman, Michael Hurwitz and Jonathan Smith, in the latest issue of the AEA policy journal:

We demonstrate that heat inhibits learning and that school air conditioning may mitigate this effect. Student fixed effects models using 10 million students who retook the PSATs show that hotter school days in the years before the test was taken reduce scores, with extreme heat being particularly damaging. Weekend and summer temperatures have little impact, suggesting heat directly disrupts learning time. New nationwide, school-level measures of air conditioning penetration suggest patterns consistent with such infrastructure largely offsetting heat’s effects. Without air conditioning, a 1°F hotter school year reduces that year’s learning by 1 percent. Hot school days disproportionately impact minority students, accounting for roughly 5 percent of the racial achievement gap.

Here is the (gated) AEA link, here are alternate versions of the paper.


At last, a simple explanation of the superiority of a Scottish education over an English one, a superiority that lasted for centuries and was acknowledged in both countries.

Though how is it consistent with the fact that with just a couple of decades of devolved government in Scotland the superiority seems to have vanished?

Scottland has the largest percentage of bus driver deaths on the entire planet, in square root analysis of applicable data streams.

Scotland's best poet was Robbie Burns, and, to tell the truth, he was not that good of a poet.

And nobody cares which stink-loving lab rat got first to some invention.

Scotland and the Scots have many things to be proud of, poetry and the humility to take advantage of their God-given gifts are not the first things that come to mind.

(Scotland's best English-speaking poet ....)

If warm weather hurts learning, what will be the impact of closing schools for 1-2 semesters?

"Hot school days disproportionately impact minority students, accounting for roughly 5 percent of the racial achievement gap."

And closing schools for 1-2 semesters will widen the gap as upper-middle class parents homeschool and hire tutors for their children. Heads I win, tails you lose.

Especially handicapped female minority students.

Heat is bad for learning, but good against Covid-19. Don’t sit in the AC flow.

A binary choice- die or flip burgers the rest of one's life.

Where is your evidence?

Coronavirus don't clearly have the seasonal traits of Alphainfluenzavirus even though both jump (mostly) from animal to humans.

And it's not clear H1N1 strains are seasonal. In 2009, the novel strain peaked in mid summer and ended at the end of the year, when the vaccine was readily available, but only about a hundred million were vaccinated plus 50-60 million who had it, so half the
US population was susceptible, so it would be expected to continue into early spring.

The obvious guess would be that "Presence of air-conditioning" variable is confounded with neighbourhood level wealth at a finer grained level that their (I'm presuming) necessary neighbourhood control.

It's a interesting critique. Census data should give them pretty good data on neighborhood wealth so in theory they can control for the effect that you describe.

But yeah to the extent that there are unobserved or uncontrolled-for differences in wealth or other SES variables, they'll find a correlation between air conditioning and PSAT scores which is really due to those unobserved differences and not due to air conditioning.

It wouldn't even have to be wealth per se. Maybe some neighborhoods have families who care a lot about education. Compared to other neighborhoods with the exact same wealth levels, the schools in those neighborhoods are likely to have higher-performing students -- and also more likely to have air conditioning because the parents are insisting on it.

But maybe they can control for that by estimating parental commitment to education? E.g. by looking at parent education levels in the neighborhood, maybe percent Asian families, typical jobs or industries, etc.

That's schoolbook learning. Over the centuries, millions of children in tropical, subtropical and desert climates learned how to fletch arrows, thatch huts, make rope out of grass, track game, prepare manioc flour, identify medicinal herbs, perform sacred rituals, memorize epics, do trepanation, make clothing out of animal skins, and the countless other tedious-but-essential survival crafts of pre-industrial life. And then their children learned them.

Egypt was a pretty hot place, where lots of precise learning took place, at a time when the men up north were still painting themselves blue. Heat didn't inhibit the ancient civilizations of Babylon and India from developing and passing down complex cultures.

There are too many economists with time on their hands.

Well, they didn't have AC growing up.

Hot days? Turn down the damned central heating!

Obvious answer is to make every classroom a walk-in freezer.

Maybe that is why everyone was so stupid before 1915. Without Willis Carrier's work civilization would never have advanced to the glorious heights today capable of defining works of global superiority such as 50 Shades of Gray, the Twilight Saga, and the NYT 1619 project.

Do those slave stories trigger you, hun?

Thank you

Eric Arthur Blair

Another study affirming common sense, sweet.

Economists donning on the role of management consultancy hiring big staff (Bihar, Odisha, UP anyone) while they remained 'white' in the land of milk and honey (Grapes of Wrath). Long live Lal, Deepak Lal!

Nice bow he wears, red, like his name - lal.

We'll meet again, as the Queen says.

From the Rothschild generation. We'll meet again, so goes the song.

This is consistent with well established findings for decreased workout with higher temperatures. A considerable portion of the economic damage from global warming results from heat related reduction in productivity. Some good news is factory gate prices of decent quality solar panels are now down to 20 cents per watt.

Maybe a Straussian take on this would be that arresting and turning back global warming would increase profits without the expense of providing AC to the workers themselves, since management already enjoys an optimum in their own environment.


I see what you did there and I second this suggestion.

Look, I do what I do.

It's better you keep doing what you do. Talking to Congress with the veneer of bookshelf. Then there's another one - wearing the jacket inside out. But he was a kid then.

You forgot us. But we'll let Covid-19 separate the chaff from the grain : men from boys or boys from men? Trump/Biden.

When is TC acknowledging it has been a huge mistake to impose lockdown?

Men/boys are anyway going to come a cropper!

Did they control for the inverse relationship between heat and clothing? I'm not sure about heat, but spaghetti strap tank tops definently inhibited my learning during high school.

Heat will kill the virus but the human survivors will be stupid. I disagree: all those northerners moving south were stupid before they arrived.

+1. Dumb northerners gonna dumb.

By what mechanism would heat disproportionately inhibit minorities?

All the thermal scales were invented by white men.

"By what mechanism would heat disproportionately inhibit minorities?"

Urban schools tend to be older and thus not have air conditioning and to also have a higher minority proportion of the school population.

According to this roughly 1/4th of NYC classrooms don't have A/C, but they are currently being retrofitted.

“More than a quarter of the city’s classrooms, about 11,000 classrooms, don’t have air conditioning,” New York City Councilman Brad Lander told WCBS radio in the early spring."


Hot classrooms were a regular feature of my schools in Kentucky- we started school every year around August 20th- still the deep Summer heat and humidity, and the schools never had the money for AC. It usually only was a problem after about 1 p.m., though. It definitely saps your energy and desire to pay attention to anything.

HVAC contractors have been publicizing this for years, based on earlier studies. The question becomes: "Will students that learn in a temperature and humidity optimum be able to adequately function in a less favorable situation?"

It takes around 14 days to physiologically adapt to increased temperatures. But people can still complain about it long afterwards if it's not what they're used to.

But if students are exposed to high temperatures in the playground... Oh wait, do US schools even have playgrounds? Okay, if they are exposed to high temperatures walking or riding to school or at home or work, they are likely to already be acclimatized.

The US military makes extensive use of air conditioning to reduce heat related declines in performance and reduce performance declines in unacclimatized individuals.

There was a study a couple of years ago at an East Coast university that took advantage of the fact that not all of the dormitories were air conditioned. Students were prompted from time to time with questions via a mobile phone app that were basically from an IQ test. The site conditioned dorm residents did better.

" The site conditioned dorm residents did better."

That's as likely to be selection bias as anything else. The smarter, better prepared students were probably more likely to put in requests early for the newer, air conditioned dorms, and the less well prepared students came in late and were left with the older, un-airconditioned dorms remaining. So, unless you can truly randomly assign dorm residency, you are left with too much bias in the outcome.

Great, we'll get right on this when the teachers' union gives the all-clear to re-open in 2024

An imp result.
Is there any literature that explores kids who study in schools with air conditioning in a hot & humid climate, especially in developing countries, having lower immunity and other related issues as adults or alternatively, these kids end up spending most of their time indoors with AC and hence, live restricted lives?

I think it was the famous Indian mathematician Ramanujan who praised the cold British weather as an accelerator of thinking, comparing it positively to the numbing heat of his native India, which sapped human bodies of energy.
Unfortunately the same cold British weather took his life at only 27, killing him with TBC.
But the explosive growth of high-tech industry in Bangalore, a city not very far from the equator, is almost definitely dependent on cheap and available air conditioning.

Similarly many Americans have said that the economic rise of the southern states in the US would've been curtailed if not for air conditioning.

If it's hard for workers to be productive when temperatures are high, it's easy to believe that it's also hard for students to learn.

Without AC the population of Phoenix would be just enough to service the trains passing through from Chicago to LA. Las Vegas would be a small collection of gas stations and diners.

"Similarly many Americans have said that the economic rise of the southern states in the US would've been curtailed if not for air conditioning."

I think so.

I can remember even during the 1980's that we were taking math qualifying scores on a day when the air conditioning wasn't working in that wing of the TN high school I was at. My score was awful, even though my previous results where very good. I found it impossible to deeply concentrate on the math problems on a timed test when the normally cool room was in the high 80's.

The first time I sat in an air conditioned classroom was in college. Public schools, where boys were required to wear long pants and socks and shirts with a collar, were not air conditioned when I was growing up. And very few homes were air conditioned. And this was in the South. My grandmother, who moved to the South from western Pennsylvania when she was an adult, attributed her longevity and good health to the mild climate in the South. Neither her office (she was a physician) nor her home was air conditioned. Mild climate? I suppose it wasn't as hot back then, but it was still hot. Yet, she attributed her longevity and good health to the climate in the South. Today, I cannot imagine living in the South without air conditioning. But I did back before I became accustomed to air conditioning.

Would there be similar indications for the introduction of AC in cars? Fewer accidents, less road rage, fewer speeding tickets?

This, rather than the supposed need for children and teens to work on the family farm (which affects only a few kids post-WWII when farming became almost entirely mechanized), is probably the reason why school lets out for 10 weeks in the summer time.

Related question, has the addition of air conditioning led to more random days off during the school year? That is, the cheapest way to provide a cool classroom is to cancel Christmas break, MLK, President's day, Teacher Union day, etc.

That said, much of the tourism business relies on a student workforce.

And that's why we should keep the office cooler. Glad that question is finally settled.

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