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I'm a cyclist and a PhD student, and I've noticed some patterns in the way that my exercise habits affect my productivity. I get a lot of data from every ride. While I'm riding, I measure heart rate and power, and if I'm outside, I also measure distance and speed. I've found that the total amount of energy that I produce, as measured by the power meter on my bike, is a useful metric for how I should expect to feel the rest of the day and the next day. In particular, if I generate between 800 kJ and 1000 kJ, I usually feel alert, but not worn out. If I do less, I feel like I've not had enough exercise, and I either feel restless or like my body is in lazy recovery mode. If I do more, I feel physically worn out enough that it's hard to work for an extended period of time, especially on the days that I am working in the lab.
What I think is most curious about this is that it is relatively independent of my fitness or the intensity of the ride. If I go balls-out the whole time, it takes slightly fewer kJ to make it hard to focus, and if I go super easy, it takes a bit more. It's the same with fitness. The difference between the power I can sustain for an hour when I'm in form for racing vs when I've barely been riding at all is about 25-30%, but the difference in the amount of mechanical work to make me unproductive is about 10%. (You might notice this gives me an incentive to stay in shape; I can do the same amount of work for the same productivity boost in less time when I'm more fit.)
So, what's definitely true is that the amount of work I put in on the bike is a useful metric for maximizing my productivity. What's unclear is if the amount of work is in some way fundamental to the mental state that it puts me in. The most obvious possibility is that it mainly has to do with the number of calories I burn; this is consistent with the finding that I need to do more work to feel tired when I'm more fit, since training will make you more efficient. But it's not obvious to me why this would be the case. When I'm in poor shape, an 800 kJ ride will have a much more drastic effect on my blood sugar than it will when I'm fit enough to race. It would be useful to venture outside the 800-1000 kJ range on days when I need to get work done.
I don't really know enough physiology to get any further than this. Does anybody else have experience with this sort of thing? Does anyone have empirically testable hypotheses? (Non-testable or not-testable-for-me hypotheses may be interesting as well.)
People like to think of their brains as some kind of separate regulating thing compared to the rest of their bodies. They're not. Everything is mushed together in a common mileu and the sheer degree of crosstalk between your nervous system and everything else is enormous, through both the general chemical environment and fibers that have nothing to do with the consciously available senses.
Humans did not evolve sitting around writing theses. They evolved spending energy in an active way, possibly with wide variation from day to day. It is completely unsurprising to me that there is an amount of energy use that makes one feel clearer and more productive compared to the sedentary graduate student, and that that can vary from person to person and over time in the same person as their physiological state adapts and changes.
It is completely unsurprising to me that there is an amount of energy use that makes one feel clearer and more productive compared to the sedentary graduate student, and that that can vary from person to person and over time in the same person as their physiological state adapts and changes.
I don't think that anybody here is surprised by this. What's surprising is not that there is an amount of exercise that is required for me to feel alert and productive, it's that the relationship between my mood and my exercise seems to follow a single, simple, specific rule. You explain the reasons why this should be surprising in your first paragraph. To illustrate why this seems surprisingly simple, here is a list of things that seem not to affect my productivity, holding total work constant:
-Heart rate
-Duration
-Time of day
-Eating before or during the ride*
-How fatigued I am from the day before**
-Average Power
-My functional threshold power at the time (a measure of fitness)
The last three of these are metrics that are part of a physiological model. The model is somewhat simplistic, given the complexity of humans that you have mentioned, but the metrics have proven to be useful for athletic training (anyone who is interested in a more detailed description, which is still written for the layman, should check out Training and Racing with a Power Meter by Coggan and Allen). More to the point, there's no particular reason (that I can see) to expect total work to win out over any of the other things on this list.
But I do notice two things, having actually written down this list. First, each of these does seem to have a small non-zero effect. As I already mentioned, doing a little more than 1000kJ over a longer duration does seem to be okay, and my FTP does seem to shift my ideal amount of work a bit. Second, these are tightly coupled to each other. You can boil duration, average power, total work, normalized power, TSS, and FTP down to four variables, one of which is total work, and another of which will usually be 90% determined by total work. Furthermore, fatigue and how much I eat will have an effect on how much of a work I'm able or willing to do on a given day. This all means that it would be very easy to mistake a more complex relationship between some or all of these factors and my mood/cognition as a simple one, especially a simple rule that is bent slightly by external factors. I feel like this eliminates much of the confusion for me (the lesson here being that when I'm confused, I should stop, write down my confusion, and stare at it). However, it does not offer a strategy for venturing too far from the 900kJ rule without consequence.
That's some neat data and observation! Could there be other substantial moderating differences between the days when you generate ~900 kJ and the days when you don't? (E.g., does your mental state before you ride affect how much energy you generate? This could suggest a different causal relationship.) If there are, maybe some of these effects can be removed if you independently randomize the energy you generate each time you ride, so that you don't get to choose how much you ride.
To make this a single-blinded experiment, just wear a blindfold; to double blind, add a high-beam lamp to your bike; and to triple blind, equip and direct high beams both front and rear.
… okay, there will be no blinding.
Could there be other substantial moderating differences between the days when you generate ~900 kJ and the days when you don't? (E.g., does your mental state before you ride affect how much energy you generate?
This could be the case, or there could be a common cause between the total work I do and my mood for the day. What makes me think this is less likely is that, when I'm following a training plan, the total work for the ride is largely determined days or weeks ahead of time. Then again, I will modify the day's workout on a training plan if I'm feeling shitty. Or it could just be that I noticed the pattern once when it happened by chance, then I expected it to continue, so it did (that is, it's more of a placebo than anything else). Then again, it wouldn't be hard for small effects like this to add up to the observed effect.
I actually did think about blinding it. I could modify some existing software to give me an intensity or duration that I don't know ahead of time, and that I don't have in front of me while I'm riding, and I could even not look at what it was until days or weeks later when I'm analyzing the results (or I could get even more hardcore and have someone else analyze it). The problem is that most of the motivation mechanisms I have for actually doing a worthwhile ride indoors require me to have access to a lot of this data. It would sort of be like trying to stay motivated in a game where you have no access to your score or whether you've eliminated another player.
If you buy a Humble Bundle these days, it's possible to use their neat sliders to allocate all of the money you're spending towards charities of your choice via the PayPal giving fund, including Lesswrong favourites like MIRI, SENS and the Against Malaria Foundation. This appears to me to be a relatively interesting avenue for charitable giving, considering that it is (at least apparently) as effective per dollar spent as a direct donation would be to these charities.
Contrast this with buying games from the Humble Store, which merely allocates 5% of money spent to a chosen charity, or using Amazon Smile which allocates a miniscule 0.5% of the purchase price of anything you buy. While these services are obviously a lot more versatile in terms of the products on offer, they to me are clearly more something you set up if you're going to be buying stuff anyway rather than what this appears to be to me, a particular opportunity.
Here are a couple of examples of the kinds of people for whom I think this might be worthwhile:
People who are interested in video games or comics or whatever including any that are available in Humble Bundles to purchase them entirely guilt-free, with the knowledge that the money is going to organisations they like.
People who are averse to more direct giving and donations for whatever reason to be able to support organisations they approve of in a more comfortable, transactional way, in a manner similar to buying merchandise.
People who may be expected to give gifts as part of social obligation, and for whom giving gifts of the kinds of products offered in these bundles is appropriate, to do so while all of the money spent goes to support their pet cause.
Huge apologies if this is an inappropriate place to post this, but I'm having a situation where I really want a quantitative answer so I can do a cost-benefit analysis, and can only seem to get qualitative ones from e.g. my doctor and the internet. And also, there seem to be enough of us transgirls on here that someone might actually know about this.
Anyways, being on Hormone Replacement Therapy (HRT) sometimes makes you infertile, and the chance someone will be infertile after being on hormones a while is definitely a function of how long one has been on HRT. But, it's entirely unclear-to-me what this function looks like; I'd wanted to ask my doctor, but I've always had trouble getting doctors to give me their best quantitative guesses and just put numbers on things related to my health, so, here I am.
(For context, I've been on HRT for 3.5 months).
Possibly relevant: https://srconstantin.wordpress.com/2016/10/06/cross-sex-hormone-therapy-female-hormones/
Anyways, more personal info: I don't currently think I'll want bio kids, but sperm banking is cheap enough (a quick Google search says that at best, it'd be $1,000 initially and then $200/year) that it's still an obvious win if I place a 10-20% chance on me changing my mind about wanting kids in the future. I'd have banked before starting hormones, but 1) I was actually too poor at the time and 2) hormones help me not self-harm, so I didn't want to wait to start HRT until after I had money to bank a sperm sample.
I recall that being off of HRT for relatively longer before banking a sperm sample increases the odds somewhat, too. So, when I have more info, I'll do some more internal cost-benefit analyses on how (being more likely to self-harm) trades off against (being more likely to successfully preserve a sample) at various values of (how long I'm off HRT before banking).
Also, this question is obviously super difficult, and I plan to upvote helpful but non-thorough quantitative-ish responses to this comment with my main account. I think that only upvoting super-well-researched responses to this wouldn't incentivize the right sort of discussion here.
Thanks!
I think you are going to have to find the relevant information yourself by looking through scientific papers. I don't think that asking your doctor will be sufficient. It is rare to find a doctor who keeps up with reading all of the newest scientific journal articles.
Where your doctor might help is in explaining the mechanism by which the infertility may happen, to help you get more keywords with which to look stuff up.
It may be that quantitative answers for your questions are not available at all. From the link you mentioned, it says that as of 2009 there have been no studies of fertility after prolonged use of estrogen. For people unfamiliar with the state of medical science, it can be disorienting to learn that a lot of things simply haven't been studied. There is so much that we as a civilization and society do not know.
From: https://srconstantin.wordpress.com/2016/10/06/cross-sex-hormone-therapy-female-hormones/
Risks of Hormone Therapy: Infertility
Estrogen therapy usually eliminates the production of sperm. In 7 out of 10 trans women on estrogen, there was no >spermatogenesis.[53] A single male given estrogen had a pronounced drop in sperm motility and density by 4 weeks of >estrogen treatment, though it did recover after discontinuation of treatment.[54] As of 2009, there have been no studies >of restoration of spermatogenesis after prolonged treatment with estrogen. [52]
And those references are:
[52]Hembree, Wylie C., et al. “Endocrine treatment of transsexual persons: an Endocrine Society clinical practice >guideline.” The Journal of Clinical Endocrinology & Metabolism 94.9 (2009): 3132-3154.
[53]Thiagaraj, D., et al. “Histopathology of the testes from male transsexuals on oestrogen therapy.” Annals of the >Academy of Medicine, Singapore 16.2 (1987): 347-348.
[54]Lübbert, Horst, Inka Leo-Roßberg, and Jürgen Hammerstein. “Effects of ethinyl estradiol on semen quality and >various hormonal parameters in a eugonadal male.” Fertility and sterility 58.3 (1992): 603-608.
If I was going to attempt to answer this question, I would start by reading those papers, to orient myself. I would also put as many keywords as I could think of into Google Scholar to see if I could find more papers on similar topics. https://scholar.google.com
A quick search for "Hormone Replacement Therapy fertility cross-sex" and "male fertility estrogen hrt" found some papers on diabetes risks, cardiovascular risks, but not much about fertility. The search that mentioned estrogen seemed to find more specific articles and included studies of environmental exposures such as:
Effect of Occupational Exposures on Male Fertility: Literature Review Sheiner et al, Industrial Health, Vol. 41 (2003) No. 2 P 55-62 http://doi.org/10.2486/indhealth.41.55
Wouldn't it be nice if there actually was good quantitative data available? I'm getting an impression from a quick search on the topic that it may not be. I think my next step, after reading a bunch of papers to get a better understanding of the topic, would be to contact some of the researchers I respected after reading their work, to ask them if they are aware of any studies. If the individual researchers doing work in the field aren't aware of any, then they probably don't exist.
Nice! I appreciate the response. I'll read the papers you've mentioned and ask my doctor about mechanisms and keywords. For reasons of severe akrasia, I don't expect to report back here or write anything up.
In the spirit of "flipping a coin a few times actually gives you a decent amount of info on whether it's fair", I might ask around for anecdotal evidence on people who've tried banking after being on hormones a while.
Thank you for writing this. <3
If there is no anti-gravity force, then how can an galactic scale empty section be "pushing" us toward the Great Attractors....
"Discovery of the “Dipole Repeller” confirms that both attraction and repulsion are at play in our extragalactic neighborhood"
http://new.huji.ac.il/en/article/33403
Some decent visualizations linked, and an original one on Utube from a French team is one of the coolest large scale animations i've ever seen...
Edit: and there it is, linked at bottom of viz page! http://irfu.cea.fr/cosmography
Are you just wondering what 'pushing' means in this context? Or speculating about the existence of anti-gravity?
I'm pretty sure that this is just interpreting as region of low density as 'pushing' because it 'pulls less' than a region of average density would.
This is similar to how electron 'holes' in a metal's atomic lattice can be treated as positive particles.
It appears the article is showing an increase in speed from the low density region, a repulsion, as an addition to the attractors forces.
"that our galaxy is not only being pulled, but also pushed. In a new study in the forthcoming issue of Nature Astronomy, they describe a previously unknown, very large region in our extragalactic neighborhood. Largely devoid of galaxies, this void exerts a repelling force on our Local Group of galaxies.
“By 3-d mapping the flow of galaxies through space, we found that our Milky Way galaxy is speeding away from a large, previously unidentified region of low density. Because it repels rather than attracts, we call this region the Dipole Repeller,” said Prof. Yehuda Hoffman. “In addition to being pulled towards the known Shapley Concentration, we are also being pushed away from the newly discovered Dipole Repeller. Thus it has become apparent that push and pull are of comparable importance at our location.”
When you bring the paper up it indicates that they are talking about a lack of density in a region, not a repulsive force.
You can treat it as a repulsive force, in the same way you can treat the absence of an electron in a semiconductor as a particle with a positive charge (a 'hole'). With matter density from the bulk of the rest of the universe all around it, the gravity of that matter pulls things near the edge of the low density region away from it and this is functionally similar to repulsion away from the void. The paper finds that the flow away from the low density region towards the generalized rest of the bulk universe is about as important for our galaxy's motion as the attraction towards the local overdensity of the various nearby attractors.
A math problem which a child can understand. But who can solve it?
https://protokol2020.wordpress.com/2017/01/29/a-topological-problem/
My immediate reaction, without actually doing any calculation or diagram-drawing or whatever, is:
Jnvg, jung?, qbrfa'g gur nirentr ahzore bs arvtuobhef unir gb or fgevpgyl yrff guna 6 sbe ernfbaf qrevivat sebz Rhyre'f sbezhyn? Vs fb, gur nafjre vf gung gur fvghngvba qrfpevorq vf vzcbffvoyr, ertneqyrff bs ubj znal ynlref bs ynaqybpx lbh unir.
But the fuzzy combination of intuition and hazy memory that tells me that may be all wrong.
Well, imagine the chessboard. There are 36 fields with 8 neighbours, 24 with 5 neighbours, and 4 with 3 neighbours.
Which gives you an average greater than 6.
There is a quadripoint between Botswana, Namibia, Zambia and Zimbabwe, for example.
Oh! You count countries that are only adjacent at corners as neighbours? That changes things a lot. (And surely isn't the usual definition.) I think you should make that explicit in the statement of the problem.
Perhaps, but it follows.
It happens also at the Game of Life by Conway, at the game of chess and at many related games, as well as in real life geography.
Tvira gung pbhagevrf ner nyybjrq gb zrrg ng gurve pbearef V oryvrir gur fbyhgvba vf avargrra pbhagevrf, naq V pna cebir vg ba bar fznyy pbaqvgvba.
Yrg gur ahzore bs a-ghcyl ynaqybpxrq pbhagevrf or nv sbe v terngre guna be rdhny gb mreb, n0 orvat gur ahzore bs pbhagevrf ba gur pbnfg. Fvapr pbhagevrf ner nyybjrq gb zrrg ng gurve pbearef vg'f rnfl gb znxr n znc jurer nyy a-ghcyl ynaqybpxrq pbhagevrf zrrg nyy gur (a+1)-ghcyl ynaqybpxrq pbhagevrf (sbe rknzcyr unir nyy pbhagevrf orvat pbapragevp evatf, naq gura sbe rnpu a unir n "cvapu" jurer nyy gur a-ghcyl naq (a+1)-ghcyl ynaqybpxrq pbhagevrf zrrg ng n fvatyr cbvag). Pyrneyl ab fbyhgvba pna or znqr jbefr ol nqqvat fhpu obeqref, naq urapr jr pna nffhzr gur fbyhgvba unf guvf sbez. Fb vg erznvaf gb svaq ahzoref nv fhpu gung gur pbaqvgvbaf va gur ceboyrz ner fngvfsvrq.
Yrg hf nffhzr gung n6=1 naq gung nv=0 sbe v>6 (guvf vf gur fznyy pbaqvgvba gung V pnaabg cebir). Gur gbgny ahzore bs pbhagevrf vf gur fhz bs gur nv, naq gur gbgny ahzore bs arvtuobhef vf gur fhz bire v bs nv(n(v-1)+nv+n(v+1)-1). Jr unir fvk ahzoref (anzryl gur nv sbe v orgjrra mreb naq svir) gung jr jvfu gb bcgvzvfr. Yrg hf gel gb svaq gur bcgvzny inyhrf bs gurfr nv nzbat gur erny ahzoref. Guvf jvyy tvir hf n ybjre obhaq ba gur ahzore bs pbhagevrf arrqrq, fvapr nal vagrtre fbyhgvba jvyy nyfb or n erny fbyhgvba. Jr pna nffhzr gur nirentr ahzore bs arvtuobhef vf pbafgenvarq gb or rknpgyl fvk, fvapr nal fbyhgvba jvgu gur nirentr terngre guna guvf pna or vzcebirq ol erqhpvat nal bs gur nv.
Fbyivat gur ceboyrz hfvat Yntenatr zhygvcyvref tvirf gung gur fhz bs gur nv vf ng yrnfg 18.53. Urapr gur zvavzhz cbffvoyr vagrtre fbyhgvba vf avargrra. Va snpg guvf vf npuvrinoyr, sbe rknzcyr gnxvat gur nv gb or (va beqre bs vapernfvat v) svir, gjb, guerr, gjb, gjb, sbhe, bar. Guvf fbyhgvba (naq fbzr bgure fbyhgvbaf) pna or sbhaq arne gur erny ahzore fbyhgvba.
EDIT: Here's a picture of such an island: http://i157.photobucket.com/albums/t43/Macbi/sextuplylandlocked.png?t=1485712658
Nyy gung erznvaf vf gb cebir zl nffhzcgvba gung gurer ner ab frcghcyl be jbefr ynaqybpxrq pbhagevrf, naq gung gurer vf bayl bar frkghcyl ynaqybpxrq pbhagel. Ohg V whfg ernyvfrq guvf vf boivbhf. Nal frcghcyl be jbefr ynaqybpxrq pbhagel pna or ghearq vagb n frkghcyl ynaqybpxrq bar naq gur fbyhgvba vf fgevpgyl vzcebirf. Yvxrjvfr nyy ohg bar frkghcyl ynaqybpxrq pbhagel pna or ghearq vagb n craghcyl ynaqybpxrq bar.
Bxnl, abj V'ir sbhaq n fbyhgvba jvgu bayl guvegrra pbhagevrf. Gurer'f bayl bar a-ghcyl ynaqybpxrq pbhagel sbe rnpu a, rkprcg sbe fbzr inyhr bs a orgjrra bar naq svir sbe juvpu gurer ner frira a-ghcyl ynaqybpx pbhagevrf. V thrff gur fbyhgvba V sbhaq orsber jnf n fgngvbanel cbvag ohg abg n tybony bcgvzhz, bbcf. (Vg'f cebonoyl gur tybony crffvzhz tvira gung rnpu pbhagel obeqref fvk ba nirentr naq rnpu a-ghcyl ynaqybpxrq bar obeqref rnpu (a+1)-ghcyl ynaqybpxrq bar.)
V'z abg fher ubj gb cebir zl arj fbyhgvba vf bcgvzny.
EDIT: Image of new attempt: http://i157.photobucket.com/albums/t43/Macbi/sextuplylandlocked2.png
The image is in order.
Of 13 states, 9 states have 8 neighbours each. 2 have 2 neighbours each. And 2 have only 1 neighbour. 98+22+2*1=78.
And 78/13=6, which is the average number of neighbours at least required. Well done.
Work in your variable setup with a0 through a6. You were wondering how to handle countries that are more than sextuply-landlocked; I think the easiest way is to dump them into a6 regardless of how excessively landlocked they are. We want to prove that if a0,...,a6 >= 1 and a0+...+a6 <= 12, then the sum of ai(a(i-1)+ai+a(i+1)-1) is smaller than 6*(a0+...+a6). A simple way to do that is to enumerate all possible tuples, which took a few minutes of programming for me and a few milliseconds of runtime on my computer.
You can also work out a proof without a computer using the technique of "smoothing" (or anti-smoothing, rather). Suppose we have fixed a0+...+a6 and want to maximize the sum of ai(a(i-1)+ai+a(i+1)-1); we do this in order to show this maximum isn't large enough. You may as well have a0 = 1 because anything in a0 is more productive in a1; it is adjacent to strictly more things. (In other words, replace (a0,a1) with (1,a0+a1-1).) The symmetric logic applies to a6 = 1.
Now that we have a0 = 1, consider the effect of replacing (a1,a2) with (1,a1+a2-1). One may compute that this increases our sum by 2(a1-1)(a3-1), or in other words, doesn't decrease it. The same logic applies when a0 = a1 = 1 and we continue to push stuff over. The final result is that for any given sum a0+...+a6, the maximum sum can be achieved with a0 = a1 = a2 = a3 = a4 = a6 = 1 and a5 free. (In fact, the maximum is achieved whenever there are one or two consecutive ais other than a0 and a6 that are not 1.) Finally, you just check that a0+..+a6 <= 12 doesn't work.
The same logic implies that when a0+...+a6 = 13, the only way you can have an average of at least 6 is if its exactly 6.
The question is, whether this 13 is the minimal number indeed. And the question is, whether there is a solution with an average number of neighbors greater than just 6.
I plan to output all the solutions up to some number. They will be conjectures like this one, open for an improvement, or for a proof.
Something like this:
For almost a week the Less Wrong page has consistently been taking 1-2 minutes to load when I load it the first time, although it is faster to navigate to other pages once I am there.
This has not been happening with any other website, which makes me suspect that there might be some issue that has at least some aspect on the side of the site.
Books don't get better for being new/current.
Goodreads works quite well for me to see which books rationalists like.
To link to a bunch of LW people (and two people I know from QS at the end):
https://www.goodreads.com/user/show/11004626-gwern Gwern has read more than enough books ;)
https://www.goodreads.com/user/show/27547209-tara
https://www.goodreads.com/author/show/6475631.Kaj_Sotala
https://www.goodreads.com/user/show/14875421-anna
https://www.goodreads.com/user/show/1407758-michael-smith
https://www.goodreads.com/user/show/35213338-eliezer-yudkowsky
https://www.goodreads.com/author/show/7339967.Leah_Libresco
https://www.goodreads.com/user/show/28602450-vladyslav-sitalo
https://www.goodreads.com/user/show/2257756-jonah-sinick
https://www.goodreads.com/user/show/1431750-nick
https://www.goodreads.com/user/show/9829927-jazi-zilber
My own Goodreads account: https://www.goodreads.com/user/show/17754535-christian-kleineidam
Do people feel like the Newcomb paradox (one-boxing yields the better result, it is clearly preferable; two-boxing only means taking an additional 1000$ through a decision that can't possibly have an effect on the 1 million, it is clearly preferable) been resolved through Anna's post in the Sequences (or others)? I strongly feel that I have a solution with no contradictions, but don't want to post it if it's obvious.
While the article linked is interesting, I find the comments section interesting as well.
Talk of Monsanto shills, source dumping, accusations flying left and right.
Just out of curiosity, I want to see the reaction of this community.
Reaction to what? Neither the campaign against glyphosate, nor a subreddit getting excited are news.
When you bring the paper up it indicates that they are talking about a lack of density in a region, not a repulsive force.
You can treat it as a repulsive force, in the same way you can treat the absence of an electron in a semiconductor as a particle with a positive charge (a 'hole'). With matter density from the bulk of the rest of the universe all around it, the gravity of that matter pulls things near the edge of the low density region away from it and this is functionally similar to repulsion away from the void. The paper finds that the flow away from the low density region towards the generalized rest of the bulk universe is about as important for our galaxy's motion as the attraction towards the local overdensity of the various nearby attractors.