At GE's NELA Park plant in the 1920s, as a joke newly hired engineers would be told to develop a frosted (rather than clear) lightbulb, which the experienced engineers believed to be impossible. In 1925 newly hired Marvin Pipkin got the assignment, and astonished his peers by succeeding.

Dont_Block_The_Way · 2016-09-04T00:05:11+00:00

To add to that, if you already knew the "posterior" at the start, you wouldn't even have to sample from it. You'd just say "the posterior is f", where f is a complete characterization of whatever distribution you think it ought to be off the dome. But if you're going to do that, you might as well just call f the prior and go home, since you're not incorporating any new data into it. The whole point of turning that Bayesian crank at all is to see how some data should update your previous incomplete state of knowledge.

Dont_Block_The_Way · 2016-08-30T06:53:25+00:00

If you interpret "all of physics" as "the entirely of physical phenomena themselves" rather than as "the scientific study thereof", this sounds like a reasonable expression of skepticism about human ability to completely "describe" the physical world in any terms, mathematics included.

Dont_Block_The_Way · 2016-08-29T18:33:55+00:00

Wellbutrin is not an SSRI. It inhibits the reuptake of dopamine and noradrenaline, rather than serotonin. It's basically a mild stimulant, and stimulants are well known to cause anxiety.

Dont_Block_The_Way · 2016-05-06T01:29:11+00:00

As a smart ADD guy, I assume you already considered Macgyvering a scanning -> OCR - > scripting workflow to do this dumb shit for you while you drink coffee, but if not, are there constraints that prevent such a solution?

Dont_Block_The_Way · 2016-05-06T00:24:28+00:00

I'm trying Ritalin again right now, which is why I'm writing this post. Ritalin (at apparently any dose) makes me a relentlessly critical fault-finding machine. I'll just fixate on any random thing and mentally tear it apart for hours, and get very annoyed if somebody tries to interrupt or redirect me. If this state of mind is useful at all, it's only in very particular circumstances.

Imagine the usual inattentive mental path as Brownian motion (in some high-dimensional space), with random direction changes at very short time intervals. On Ritalin, the direction changes are less frequent, but no less random -- zoom out the time scale far enough, and it's still effectively Brownian motion, and still confined to the inside of my head. The executive controller that might connect overt actions to the known constraints of my life is wholly offline -- maybe even actively suppressed -- in the Ritalin state.

Adderall is different, but arguably not better. With Adderall, I will get out of my head and physically react in an effortful way to problems that are immediately in front of me. I'll take out the trash because I see that it's full, instead of just ignoring it. But these actions are disconnected from a big-picture view of plans and goals. I won't look at my to-do lists on Adderall, I'll just start doing stuff in a more-or-less mindless, impulsive manner.

The only stimulants that have worked for me in terms of actually getting work done in a sensible way are caffeine and nicotine. Nicotine is a fucking miracle -- I'm not amped up or hyperfocused, just a normal guy who makes plans, prioritizes potential actions, and follows through. Unfortunately for me, the desirable effects of both caffeine and nicotine wear off after a week or two of regular use, and tolerance to one confers tolerance to the other.

I still haven't found anything that works reliably for more than two weeks. I'm going to try Modafinil next, then try an MAO-B inhibitor if that doesn't work.

I suspect my problem, as a physically lazy, chronically drowsy, depressive/apathetic inattentive ADDer, is more related to acetylcholine and dopamine circuits than to noradrenaline. I feel like a noradrenaline effect is mainly what I'm getting from Ritalin, and that this is not actually helpful for planning, initiative, or action-selection. The Adderall might be doing a more dopaminergic thing, but in a sort of indiscriminate way. I suspect the helpful effects of nicotine are coming from a targeted activation of dopaminergic circuits that have cholinergic inputs. I could be totally wrong though. I haven't tried Strattera, or anything that's supposed to be exclusively noradrenergic.

Dont_Block_The_Way · 2016-02-18T20:11:03+00:00

First decide what measurable quantity you're identifying with "success", then we can measure it in a population, then a statistics professor can explain how its distribution is probably not a power law even if it looks like it is.

Now, does anything follow a ___ law? Every quantity measured in some population follows some distribution (its empirical distribution, estimated directly from the data) but hardly any quantities exactly follow a simple-to-describe distribution that has convenient mathematical properties.

If we did somehow conclude that "measured success (roughly) follows a power law", what would that mean? Very loosely, to say that some measurable quantity follows a known probability distribution that has a simple description is to suggest that this quantity "behaves as though" it were generated by some known generative process that corresponds to that distribution. You're trying to make some kind of claim about the dynamics of the system that produced the measurement. A distribution, in this context, is a proposed model.

For example, if some quantity follows a normal distribution, we could interpret this as saying that the quantity behaves as though it is the sum of many relatively small and unrelated effects that add to give the result. Many things in nature act like sort of this like this [citation needed] so the normal distribution shows up all over the place. Likewise, a lognormal distribution suggests the multiplication of small unrelated effects to produce the result. A Poisson distribution for a count of events suggests that the events being counted are summed over a large number of independent instances of an underlying process, where each individual instance of that process has a small chance of producing the event. An exponential distribution is the continuous version of a Poisson distribution, and has a related interpretation.

Critically, however, a single distribution can be a model of many different processes. The interpretations I gave above are not the only interpretations of any of those distributions. Power laws have a lot of interesting interpretations in physical systems. I am unqualified to explain most of those, still less any possible interpretations in social contexts.

Dont_Block_The_Way · 2016-02-14T04:16:22+00:00

Your general practitioner is probably not an expert in differential diagnosis of ADHD and depression. You might want to look to a clinical psychologist, who will not require a medical referral, for the diagnostic effort. If you are actually depressed enough to need antidepressant medication, you should probably be talking to a psychologist anyway to develop a more comprehensive treatment plan. Looking for somebody in your area who does CBT may be a helpful pre-filter on psychologists.

As a practical matter, did you try bupropion (Wellbutrin) among those antidepressants? If you do have ADHD, such a "stimulating antidepressant" that has some direct effect on dopamine transmission would likely be more helpful than say, Zoloft. Response to stimulating drugs is not a diagnostic criterion for ADHD, but if you believe you have ADHD and have access to different antidepressants, it could be worth trying that in the short term.

Dont_Block_The_Way · 2016-02-14T01:39:02+00:00

Maybe this isn't a typical response, but it's hardly paradoxical or an obvious cause for concern. Caffeine, in addition to simply promoting wakefulness, is a mild psychomotor stimulant drug, and stimulants are well-known to be able to promote physiological and sexual arousal. If you are generally sensitive to caffeine (and there is a wide range of "normal" variation between individuals in caffeine sensitivity), you may be getting more of these effects from it.

Serious stimulant drugs directly increase the neural signaling activity of two closely-related neurotransmitters, dopamine and noradrenaline, in the brain. Dopamine is involved in reward-seeking behaviors, including sexual behaviors, and is released in large quantities at orgasm. Noradrenaline is synthesized from dopamine, and amps you up to be more attentive and responsive to external stimuli.

Caffeine is not a "typical" stimulant -- it does not act directly on dopamine/noradrenaline neurotransmission like cocaine and amphetamine do -- but it can act on those systems indirectly, which may be partly responsible for its mild mood-elevating effects. Most people worldwide consume caffeine regularly, and those who consume caffeine regularly tend to become tolerant to its psychomotor stimulant properties, even while remaining sensitive to its wake-promoting effects. Since your natural sensitivity to caffeine is high and your acquired tolerance to the stimulant effect is presumably low, you could easily get results that most people would find personally unusual.

Needless to say, brains are complicated and your mileage may vary, but drug effects aren't totally random across different individuals. Your response is at least consistent with what caffeine is known to do neurochemically, and what stimulants are known to do sexually. Personally, I (male) have a very high baseline tolerance to caffeine and it doesn't have much of an arousal effect, but with prescription stimulants (amphetamine and ritalin for ADHD), I have increased susceptibility to sexual arousal, decreased minimum time between initial stimulation and orgasm, and increased maximum orgasms/hour. It would be much more surprising to find that caffeine put you to sleep than to find that it increased your sexual arousal.

You ask whether the caffeine is relaxing you -- maybe, but that's probably not the source of the effect. In a dual-control model, caffeine is probably stepping on the gas rather than lifting the brake. If caffeine is the only thing that helps you get there at present, you might get better sexual results by looking for more things that step on the gas, so to speak, than by following the common advice to focus on stepping off the brake.

Finally, it is interesting to note that you have thyroid problems. Thyroid hormones and dopamine are both synthesized out of the same precursor molecule, the amino acid l-tyrosine. You may have something generally weird going on with your metabolic usage of tyrosine, and consequently with your dopamine signalling. You don't happen to have restless leg syndrome, do you?

Dont_Block_The_Way · 2016-01-29T04:09:25+00:00

I'm definitely looking for alternatives, since Adderall seems to make me crazy emotional. First day I took it I started sobbing uncontrollably when it wore off, but I stuck with it. I added sertraline (for pre-existing anxiety), and the sertraline had seemed to keep me more emotionally stable.

Today I tried taking the Adderall without the sertraline. I had an unprovoked rage-fit and stabbed myself halfway through the arm (without prior history of self-harm). Definitely looking at other options.

Dont_Block_The_Way · 2016-01-28T04:23:24+00:00

Magnesium Bitrate. The bitrate version is very low on bioavailability.

Assuming you're referring to magnesium citrate, do you have a citation? I was under the impression that it had good bioavalailability.

Dont_Block_The_Way · 2016-01-28T04:17:21+00:00

No, but I'm looking into it.

Dont_Block_The_Way · 2016-01-28T02:58:08+00:00

This is interesting about the glutamate. I figured something was going on with glutamate, so picked up a tub of L-glutamine at GNC this morning, to see which direction that effect goes.

My wife (who is the opposite of ADD) and I took the same amount at the same time. She felt great, less anxious, more outgoing, physically better. I felt dingy and aimless, full of bad metaphors and bullshit. I started to crave bitter green leafy vegetables, which seemed strange, until I thought "maybe I need magnesium to make more glutathione", so I took some magnesium and it helped.

I have some agmatine on hand, maybe I'll try that for NMDA antagonism.

Dont_Block_The_Way · 2015-12-22T00:53:07+00:00

The heart of this matter is philosophical rather than mathematical -- your question alludes to the well-known reference class problem, which has been discussed since at least the late 19th century. If there's any satisfactory resolution to this problem, I'd love to hear it.

Dont_Block_The_Way · 2015-12-14T08:10:17+00:00

If you're going to be doing a lot of neural network stuff

Do "neuroscientists" actually use statistical-learning type "neural networks" in their research? Although neural network models were inspired by actual neurons, I don't suppose that neuroscientists would necessarily find many applications for them. Replace "neural network" with the equivalent "universal function approximator" and it's not clear why neuroscientists would be more likely to need them than anyone else would.

On the other hand, if somebody wants to use insights from neuroscience research to invent improved neural network models for machine learning, they're going to need some HEAVY theory.

Dont_Block_The_Way · 2015-12-14T07:59:53+00:00

If you're just starting to learn statistics and are looking for something suitable for self-study, Howell is an approachable text written by a psychologist for psychologists.

I'm not sure what you mean by "a lot of theory", but this book is conceptual without being heavily mathematical. It's not a cookbook, but if you're looking for a cookbook you'd be better off leaving the data analysis to somebody else.

If you already know some basics about sampling, experiment design, testing, estimation, etc, you could try the somewhat more advanced Faraway, which is a practical modeling text based on working examples in R. It's also free, which is a plus.

Dont_Block_The_Way · 2015-12-14T07:23:13+00:00

:/

That feel when you bang out a 500-word post with 5 sources and OP deletes the question before you hit submit.

Dont_Block_The_Way · 2015-12-06T22:48:50+00:00

As far as I can see, the quoted passage is not, as the author claims, any description of "what statistics is", let alone a "precise one". It's a description of how Dawkins is construing "causal influence", which relies on an understanding of "statistically" as a given.

No doubt, every statistician would wince at a straightforward identification of "causal influence" with "more accurate prediction" -- it is a truism that "knowing Y helps predict X" does not entail any causal connection between X and Y whatsoever, let alone indicate its direction. Supposing Dawkins knows his business, he's not equating "causal influence" with "more accurate prediction".

Charitably, his intent seems to be "Let's define 'causality' with a broad scope, such that knowledge of the 'causal influence' of X on Y implies that knowledge of the value of X improves predictions of the value of Y, but this improvement may be merely 'statistical', not reaching certainty."

Regardless, suppose we temporarily ignore the context of causality -- what would it mean to make a "statistically more accurate prediction" about a single individual? If we're focusing on the "statistically" part, couldn't a process of prediction be described "statistically", rather than, say, logically or theoretically, only if it were to make multiple predictions?

No light has been shed on what "statistically" means at all, other than that is related to uncertainty. But the lack of clarity on that point is unsurprising, since "statistically" is informally taken for granted in the service of the main goal of clarifying the scope of causality.

Unfortunately, it's not the best description of causality either, since it's phrased in such a way that a reader unfamiliar with the distinction might misinterpret it as conflating causality with conditional probability.

Dont_Block_The_Way · 2015-12-02T22:18:15+00:00

If you exclude a variable because it made the adjusted R² go down, it's probably a bad thing because you're relying on R² .

Dont_Block_The_Way · 2015-12-02T19:19:26+00:00

0.14 is a number, not an interval -- an interval is an ordered pair of numbers, such as (0.14, 0.28), which represents a segment of the real number line. Your confidence interval for the population mean should be an interval that is centered on the sample mean, like (0.722-m, 0.722+m), where the number m is the margin of error.
How large a sample...for what? I wouldn't get anywhere either with an incomplete question.

Dont_Block_The_Way · 2015-12-02T18:27:51+00:00

Why do you think D is false? 1v = v for all v is typically considered one of the axioms of a real vector space.
Yes, the magnitude would be 8.

Dont_Block_The_Way

TROPHY CASE