Comment by alahonua on Born as the seventh month dies ... · 2020-07-11T07:34:16.525Z · score: 1 (1 votes) · LW · GW

This is correct, if you are excluding the case where both are boys both born on Tuesday. Otherwise you would not subtract p(A and B). But, you did not say only one, you said _at least_ one.

Comment by alahonua on Born as the seventh month dies ... · 2020-07-10T17:21:16.357Z · score: 3 (2 votes) · LW · GW

I don't think you have the dependencies quite right, because you can actually use more of the information than you do above to restrict the population from which you draw.

The real underlying population you should draw on seems to to be the population of fathers with exactly two children, of which one might be a boy born on Tuesday.

p(a two boy family given one brother was born on Tuesday) = (p(one brother born on Tuesday in a in two-boy family)) (p(two boys in 2 person families)) / p(out of all two person families, having one be a boy born on Tuesday)

which is if we say Tuesday birth is 1/7 and boy is 1/2,

(2/7) (1/4) / (2/14) = 1/2 so the Tuesday datum drops out.

Comment by alahonua on Do any mammal species exhibit an immune response in some of the herd in response to the infection in other herd members? · 2020-05-16T20:38:58.745Z · score: 6 (4 votes) · LW · GW

It is not a crazy question at all. In fact it has a variety of answers: I will summarize with a "no," a "yes," and a "no."

1. No, exposure of others to Covid-19 may cause them to become specifically immune to that virus, but it will not cause us to also become specfically immune unless we are similarly exposed to virus components themselves, not just the persons involved.

2. Yes, the fact that people near us are in distress because they are sick will probably cause us, as we too are distressed by the situation, to secrete stress hormone and related responses that will somewhat alter our immune system, for example by raising the count of neutrophilic white cells in our blood somewhat.

3. No, that particular kind of nonspecific change in our stress hormones and related effects on our immune calls is not likely to prevent Covid-19 infection in us.

Comment by alahonua on Help me with bayesian thinking re:coronavirus? · 2020-03-09T06:38:55.501Z · score: 3 (2 votes) · LW · GW

Yes, true. The exact numbers are very uncertain, but the qualitative point remains that someone who feels fever many days per winter has less chance of a similar day with fever being from covid than someone with a fever today who has had no fever for over a year.

Comment by alahonua on Help me with bayesian thinking re:coronavirus? · 2020-03-08T18:01:08.453Z · score: 6 (4 votes) · LW · GW

To answer properly you need to know the prevalence of fever of any kind. In particular, you might use the number of days with fever per year you had last year / 365, for example. If you literally never get a fever for years, I'd worry more then if you did.

P(19coro | fever) = P(fever| 19coro, about 0.5??) * P(19coro, perhaps 0.001??) / P(fever)

Comment by alahonua on Is it worthwhile to save the cord blood and tissue? · 2020-01-12T01:46:45.770Z · score: 8 (5 votes) · LW · GW

1. Not very valuable. Handling and storage costs far outweigh acquisition costs.

2. Unmatched, easy; well matched, somewhat difficult.

3. Generally it depends on the specific inherited immune characteristics of mother and child, similar to these factors in kidney donation.

4. For decades, yes, for a lifetime no.

5/6 No and sort of yes.

If you are going to donate cord blood for others, as a humanitarian thing, check with your OB/GYN about whether they know who would need to be there to ship the donation.

If you are going to save it for family use, I would do so only if you are aware of a known risk requiring use of such a donation in the baby or family, such as an inherited blood disorder or similar risk factor. If there is none, the cost-effectiveness of banking with a commercial outfit is poor unless you have inexpensive access to a liquid nitrogen-level freezer for long term storage. If the family has such an inherited disorder, check with the physicians treating it for instructions.

Comment by alahonua on How to avoid dying in a car crash · 2013-02-06T19:05:54.151Z · score: 0 (0 votes) · LW · GW

I know no one is likely to do this, but consider the safeguards taken by auto racing drivers. They are required to wear a helmet. For high speed driving helmets on all in the car would cut the death rate. That said, I doubt anyone will do this, as the inconvenience is great for a small payoff.