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Lifespan depends on month of birth (2000)

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Re: Lifespan depends on month of birth (2000)

#21

Post by ekianjo »

jedberg wrote: post #17
ekianjo wrote: post #9

Earlier quoted context omitted.

> The real reason she was such a good student in 1st grade is because she was just older. That may be an intuitive reasoning but not sure it holds true. I have seen numerous times the youngest students performing actually better in class than older ones. Do you have hard data to support this ?

I have no hard data, but I have 10 years of anecdotal data (my wife was a 4th grade teacher for ten years and saw just about 1000 students over her career). She says the younger kids definitely do worse by all measures in 4th grade, in large part because of their lack of maturity.

> in large part because of their lack of maturity.

Maybe that depends on the topic you are teaching then ?

Re: Lifespan depends on month of birth (2000)

#22

Post by ekianjo »

vlasev wrote: post #15
ekianjo wrote: post #8

Earlier quoted context omitted.

But the data in the post does not seem to be super correlated to seasons. You can see that the decrease in life expectancy occurs way before spring (as soon as February) which is still supposed to be a winter month. So the season link is weak.

I'm thinking it has to do with the continuous day/night cycle. It'll be interesting to see if there are any changes with latitude, in particular, what happens in countries closer to the equator.

But is there any rationale behind that anyway ? Do we see people born during summer being usually in poorer health than people born during November-December, let's say ?

Re: Lifespan depends on month of birth (2000)

#23

Post by ggreer »

sillysaurus3 wrote: post #4
jcampbell1 wrote: post #3

This is interesting. They seem to think it is in utero effect. Maybe Vitamin D? I wondered if they considered if the cause is age when starting school. I know that birth month has pretty powerful effects for educational attainment.

What month should I conceive my child to maximize their educational attainment? I'm only half joking.

You'll probably enjoy The Biodeterminist's Guide to Parenting[1] by Scott Alexander[2]. It's a good overview of environmental effects on cognition. There's a section on birth month, and the answer is: It's a trade-off. If you're sending your child to public school, August is best. This makes them the oldest in their grade, giving them advantages that compound throughout school. For private school, February/March might be best, as winter babies have slightly higher intelligence and social skills.

1. http://squid314.livejournal.com/346391.html

2. You may have heard of him. Scott is a resident psychologist and writer of Slate Star Codex (http://slatestarcodex.com/).

Re: Lifespan depends on month of birth (2000)

#24

Post by mod »

ggreer wrote: post #23
sillysaurus3 wrote: post #4

Earlier quoted context omitted.

What month should I conceive my child to maximize their educational attainment? I'm only half joking.

You'll probably enjoy The Biodeterminist's Guide to Parenting [1] by Scott Alexander[2]. It's a good overview of environmental effects on cognition. There's a section on birth month, and the answer is: It's a trade-off. If you're sending your child to public school, August is best. This makes them the oldest in their grade, giving them advantages that compound throughout school. For private school, February/March mig…

Well I got the shaft. Early August birthday, nearly the youngest in my grade, public school.

Re: Lifespan depends on month of birth (2000)

#25

Post by saraid216 »

desdiv wrote: post #10
jcampbell1 wrote: post #5

Earlier quoted context omitted.

Depends on the rules which vary by location, but you want your kid to be the oldest in the class. Your older kid is going to believe she is very bright in 1st grade, and have a lifetime of confidence to achieve great things. The real reason she was such a good student in 1st grade is because she was just older.

I know this sub-thread started in half-jest, but your response got me thinking: 1. Month of birth directly determines a child's age compared to their classmates. 2. An older child among younger peers performs better academically. 3. Academic aptitude is correlated with income. 4. Income is correlated with longevity. Admittedly, hypothesis #2 is iffy. And the good old "correlation is not causation" adage applies for #…

> And the good old "correlation is not causation" adage applies for #3 and #4.

It does, but it's not hard to come up with plausible causes for the correlation to support in those cases.

It is probably more accurate to say "Academic aptitutde correlates with job stability which correlates with lower overall stress levels which is part of the definition for better health which correlates with longevity."

Re: Lifespan depends on month of birth (2000)

#27

Post by peteretep »

sillysaurus3 wrote: post #4
jcampbell1 wrote: post #3

This is interesting. They seem to think it is in utero effect. Maybe Vitamin D? I wondered if they considered if the cause is age when starting school. I know that birth month has pretty powerful effects for educational attainment.

What month should I conceive my child to maximize their educational attainment? I'm only half joking.

    > What month should I conceive my child to maximize their
    > educational attainment? I'm only half joking.
I'm married to a primary school teacher. We are very definitely aiming to have babies born September to December. We aren't even slightly joking about that.

Re: Lifespan depends on month of birth (2000)

#28

Post by wobbleblob »

jcampbell1 wrote: post #3

This is interesting. They seem to think it is in utero effect. Maybe Vitamin D? I wondered if they considered if the cause is age when starting school. I know that birth month has pretty powerful effects for educational attainment.

I was wondering about that. I read somewhere else about the birth month effect for professional athletes. Kids whose birthday falls just after the season of their sport starts are up to a year older, bigger and stronger than their peers born earlier in the year, which boosts their confidence to the point that fewer of them quit.

Re: Lifespan depends on month of birth (2000)

#30

Post by ryanjshaw »

Smirnoff wrote: post #19
sillysaurus3 wrote: post #4

Earlier quoted context omitted.

What month should I conceive my child to maximize their educational attainment? I'm only half joking.

Purely speculative but people whom I know to be the most successful in education and career happen to be born between November and January. Age doesn't matter though. Some of them jumped a few years ahead of their classmates so they surely weren't the oldest in their classes. My mother did think that being the oldest helps (or as she would put it: "School and work can wait. Enjoy your childhood while you can"), so my…

Speaking from experience, being the youngest appears to have no upsides: you're expected to perform as well as people older than you which creates tons of pressure, you're probably physically smaller which can impact confidence/sports/romance, socially you're a year behind, and it only gets worse later - in many countries the legal drinking age (18) aligns with the average age of entering university which means your options for social development at a crucial stage of development are restricted further, etc.

By the time you're 30, an extra year saved going to school earlier means nothing, and the price you paid in terms of developing neurotic conditions (e.g. perfectionism) which impact confidence and social skills, is most definitely not worth it. My kids will follow a similar path to the one you outlined, and I will strongly encourage them to take a gap year before considering applying to university.

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