= 27d567bc2d48d9f40e9ccc20ea370b15)
Do you have a curriculum that works through these?
It can either be an already existing textbook or class or just a list of concepts.
It's been a while since I've thought about how to learn ecology, but maybe check out Ben Bolker's Ecological Models and Data in R? It would also be a decent way to start to learn how to do statistics with R.
Price's Equation
That is important destination but maybe too subtle a starting point.
Start with ecological models for inter-species interactions (predation, competition, mutualism, etc.) where there are more examples and the patterns are simpler, starker, and more intuitive. Roughly, death processes may depend on all involved populations but birth processes depend on each species separately. Then move to natural selection and evolution, intra-species interactions, where the birth processes for each genotype may depend on populations of all the different genotypes, and death processes depend on the phenotypes of all the different populations.
Next year I want to see an independent measure of conscientiousness, and compare this between people who bother to answer the digit ratio question and those who don't...
The conscientiousness/akrasia interactions are also fascinating, but even harder to measure. There's a serious missing-not-at-random censoring effect going on for people too conscientious to leave off digit ratio but too akrasic to do the measurement. I nearly fell into this bucket.
If you want to learn statistics by doing, try to do what gwern does.
do what gwern does
Or do the complete opposite.
The impression I get of gwern is that he reads widely, thinks creatively, and experiments frequently, so he is constantly confronted with hypotheses that he has encountered or has generated. His use of statistics is generally confirmatory, in that he's using data to filter out unjustified hypotheses so he can further research or explore or theorize about the remaining ones.
Another thing you can do with data is exploratory data analysis, using statistics to pull out interesting patterns for further consideration. The workflow for this might look more like:
- Acquire (often multivariate) data from another researcher, source, or experiment.
- Look at its marginal distributions to check your understanding of the system and catch really obvious outliers.
- Maybe use tools like mixture modeling or Box-Cox transformation to clarify marginal distributions.
- Use statistical tools like (linear, logistic, support vector, etc.) regression, PCA, etc., to find patterns in the data.
- Do stuff with the resulting patterns: think up mechanisms, do confirmatory analysis, check literature, show them to other people, etc.
A lot of what you get out of this process will be spurious, but seeing hypotheses that the data seemed to support go down in flames is a good way to convince yourself of the value of confirmatory analysis, and of tools for dealing with this multiple testing problem.
I remember Gelman saying useful stuff like this, but it's been a while since I read that post so I might be mischaracterizing it.
(Ilya, you know all of this, surely at a deeper level than I do. I'm just rhetorically talking to you as a means to dialogue at Capla. Gwern, hopefully my model of you is not too terrible.)
Do you have any suggestions for such unitary(ish) abilities?
No idea. Factor analysis is the standard tool to see that some instrument (fancy work for ability) is not unitary. It's worth learning about anyways, if it's not in your toolbox.
0 degrees Fahrenheit
For our readers who like to use SI units: That is about -17.7°C
The trick to surviving in colder climates is layering. T-Shirt plus shirt plus pullover plus a good winter jacket should do the trick. Some people like to layer trousers but for me a good pair of jeans does the trick. Look for good winter boots as feet loose a lot of heat. Cover your head with a hat, wear a scarf. Experiment with these things as there is comfort and aesthetics to be considered. Wear gloves or start getting used to walking with your hands in your pockets. If you do wear gloves take them off to shake someones hand, anything else is extremely rude.
Some people like to layer trousers
A simple way to do this is flannel-lined jeans. The version of these made by L.L. Bean have worked well for me. They trade off a bit of extra bulkiness for substantially greater warmth and mildly improved wind protection. Random forum searches suggest that the fleece-lined ones are even warmer, but you lose the cool plaid patterning on the rolled up cuffs.
In response to
Open thread, Nov. 3 - Nov. 9, 2014
Person A is an Olympic-level athlete. He can perform amazing physical feats. The limits of his ability can be scored against some sort of metric (lap time, distance jumped, etc.), and since he's working to improve on them, his own personal limits are known to him.
Person B is of average physical fitness.
Person C has a moderate chronic illness. He struggles to perform basic physical feats, but can function independently with some difficulty.
If all three of these people were secretly transplanted into an environment with lower oxygen levels and began to experience mild hypoxia, it seems that Persons A and C would both be more sensitive to this change than Person B. Person A would notice it because he would no longer be able to perform outstanding physical feats to the level he's accustomed to. Person C would notice it because he'd struggle to carry out basic activities.
[Edit for clarity: I'm not saying that Person B would never notice this, but that he would be less sensitive to it, because his performance is higher-variance and subject to less of a "state change", and doesn't have a fine, frequently-scrutinised boundary between what he can and can't do.]
Alternatively:
Person D is a voracious infovore with high reading comprehension. She's used to grappling with precise language.
Person E is an average-level reader.
Person F has some sort of reading-related disability.
It seems that Persons D and F will be more sensitive to badly-punctuated writing than Person E. For example, Person D might be able to parse a sentence in two or three plausible ways, while Person F might not be able to parse the sentence at all.
Both of these cases involve both ends of an ability distribution being more sensitive to degradation of the environment than central cases. Are there better examples? Is this a phenomenon we actually see in the real world? If so, does it have a name?
A not quite nit-picking critique of this phenomenon is that it's treating a complex cluster of abilities as a unitary one.
In some of the (non-Olympic!) distance races I've run, it's seemed to me that I just couldn't move my legs any faster than they were going. In others, I've felt great except for a side stitch that made me feel like I'd vomit if I pushed myself harder. And in still others, I couldn't pull in enough air to make my muscles do what I wanted. In the latter case, I'd definitely notice the lower oxygen levels but in the former cases, maybe I wouldn't.
So dial down my oxygen and ask to do a road race? Maybe I'll notice, maybe I won't. But ask me to do a decathlon, and some medley swimming, and a biathlon? I bet I'll notice the low oxygen on at least some of those subtasks, whichever of them that require just the wrong mix of athletic abilities.
For the reading one, I can believe this if I'm doing some light pleasure reading and just trying to push plot into my brain as fast as possible. But if I'm reading math research papers, getting the words and symbols into my head is not the rate-limiting step. If there are some typos in the prose, or even in the results or proofs, it doesn't make much of a difference. There might be some second-order effects--when I try to fill in details and an equation doesn't balance, I can be less certain that the error is mine--but these are minor.
So maybe sharpen your claim down to unitary(-ish) abilities?
In response to
Is this paper formally modeling human (ir)rational decision making worth understanding?
Seconding a lot of calef's observations.
If the new topic you want to learn is "extended behavior networks", then maybe this is your best bet. But if you really want to learn about something like AI or ML or the design of agents that behave reasonably by the standards of some utility-like theory, then this is probably a bad choice. A quick search in Google Scholar (if you're not using this, or some equivalent, making this a step before going to the hivemind is a good idea) suggests that extended behavior networks are backwater-y. If the idea of a network of things interacting to make a decision appeals to you, maybe look into Petri nets or POMDPs. Or better yet, start with something like Russel and Norvig's AIMA to get a better view of the landscape. If the irrationality part is interesting, start with Kahneman, Slovic, and Tversky's Judgment under uncertainty: Heuristics and biases, which gives you a curated collection of jargoney papers.
In response to
Anthropic signature: strange anti-correlations
In the biz we call this selection bias. The most fun example of this is the tale of Abraham Wald and the Surviving Bombers.
While maybe not essential, the "anti-" aspect of the correlations induced by anthropic selection bias at least seems important. Obviously, the appropriate changes of variables can make any particular correlation go either positive or negative. But when the events all measure the same sort of thing (e.g., flooding in 2014, flooding in 2015, etc.), the selection bias seems like it would manifest as anti-correlation. Stretching an analogy beyond its breaking point, I can imagine these strange anti-correlations inducing something like anti-ferromagnetism.
= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
= f037147d6e6c911a85753b9abdedda8d){kind=logo}
Advice/help needed: how do I study math by doing lots of exercises when there's nobody there to clue me in when I get stuck?
It's a stupid problem, but because of it I've been stuck on embarrassingly simple math since forever, when (considering all the textbooks and resources I have and the length of time I've had it as a goal) I should have been years ahead of my peers. Instead, I'm many years behind. (Truth be told, when performance is tested I'm about the same as my peers. But that's because my peers and I have only struggled for a passing grade. That's not what my standard of knowledge is. I want to learn everything as thoroughly as possible, to exhaust the textbook as a source of info; I usually do this by writing down the entire textbook, or at least every non-filler info.)
There is a great disparity between the level of math I've been acquainted with during my education, and the level of math at which I can actually do all the exercises effortlessly. In theory by now I'm well into undergraduate calculus and linear algebra. In practice I need to finish a precalculus exercise book (tried and couldn't). While I'm learning math, I constantly oscillate between boredom ("I'm too old for this shit" ; "I've seen this proof tens of times before") and the feeling of getting stuck on a simple matter because of a momentary lack of algebraic insight ("I could solve this in an instant if only I could get rid of that radical"). I've searched for places online where I could get my "homework" questions answered, but they all have rather stringent rules that I must follow to get help, and they'd probably ban me if I abused the forums in question.
This problem has snowballed too much by now. I kept postponing learning calculus (for which I've had the intuitions since before 11th grade when they began teaching it to us) and therefore all of physics (which I'd terribly love to learn in-depth), as well as other fields of math or other disciplines entirely (because my priority list was already topped by something else).
I've considered tutoring, but it's fairly expensive, and my (or my tutor's) schedule wouldn't allow me to get as much tutoring as I would need to - given that I sometimes only have time to study during the night.
Do any LessWrongers have resources for me to get my questions answered? Especially considering that, at least at the beginning until I get the hang of it, I will be posting loads of these. Tens to hundreds in my estimation.
Sorry to jump from object-level to meta-level here but it seems pretty clear that the problem here is not just about math. Your subjective assessments of how difficult these topics are is inconsistent with how well you report you are doing at them. And you're attaching emotions of shame and panic ("problem has snowballed") to observations that should just be objective descriptions of where you are now. Get these issues figured out first (unless you're in some educational setting with its own deadlines). Math isn't going anywhere; it will still be there when you're in a place where doing it won't cause you distress.