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sheefrex

103 karma · joined June 11, 2011

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sheefrex··on The Truth-Seeking Economy
Unless you illustrate the problem you wish to solve, the solution is not going to make sense.
sheefrex··on Petroleum drilling technology now used for geothermal power
A great example of productivity spillovers across industries
sheefrex··on Sophisticated Consumers with Inertia: Field Experiment
Key extract:

At the same time, consumers preempt their future inertia; 24%-36% of potential subscribers avoid subscribing when offered an auto-renewal promo. Further, offering an auto-renewal contract decreases the share of subscribers over the two years after the promo by 10%. Even though auto-renewal generates higher revenue in the medium-run due to payments from inert subscribers, auto-renewal and auto-cancel are revenue equivalent after one year, but with fewer subscribers in auto-renewal.

sheefrex··on Since spring of 2023, the world has been warmer than climate models anticipated
That doesn't surprise me. Yes, would be interesting to see those assumptions, but I guess the issue (as in most modelling of complex systems) is that as you relax the assumptions, the models become intractable.
sheefrex··on Since spring of 2023, the world has been warmer than climate models anticipated
I opened this article hoping it would mention the point about the rules concerning reduced sulfur content of the fuel used in super tanker marine shipping, and it didn't disappoint:

"A lot of people have looked at the impact of the marine shipping regulation change. If you take that and you put it into some climate model and you estimate the temperature change, right now you’d expect about 0.05 of a degree, 0.08 of a degree [of warming per year], and then building over a decade to about 0.1 degree. So that seems like it helps, but it doesn’t seem like it’s sufficient."

sheefrex··on Bursts of exercise boost cognitive function, neuroscientists find
Key extracts:

Based on the results of their modeling approach, cycling and high intensity interval training (HIIT) produced the most consistent effects in improvement of memory, attention, executive function, information processing and other cognitive functions.

"We found that vigorous activities had the largest effects," Giesbrecht said. "Also, the effects were strongest for studies that tested cognition after exercise, as opposed to during exercise. And lastly, the effects of exercise less than 30 minutes in duration were bigger than those that went beyond 30 minutes."

"Also among their findings, the team discovered that executive functioning was the key cognitive domain impacted by vigorous exercise, such as HIIT protocols."

sheefrex··on Sleep perfectionists: the exhausting rise of orthosomnia
It's probably true that not a lot of people make constructive use of their sleep data, but people just love learning about themselves: it's kind of a form of narcissism, unless you are experimenting with methods to shift the numbers some way. For my part, I use it for a lot of statistical tests.
sheefrex··on The American economy has left other rich countries in the dust
Sometimes I like to think of GDP as a measure of economic (productive) power more than well-being. But other indicators are more important for the long-term, such as those on demographics, education, debt levels, etc. You probably don't want to sacrifice those for a transient boost in GDP.
sheefrex··on Evaluating reliability in wearable devices for sleep staging
Key extract:

On average, sleep/wake classification accuracies were reported to be 87.2% based on 53 assessed devices. There was no significant difference in accuracies between devices using only accelerometer data (86.7%, d = 28) and devices using both PPG and accelerometer data (87.8%, d = 22), as determined by a t-test (significance threshold p < 0.05). All reported accuracies ranged from 79% to 96%, except for Kanady et al.’s study28, which reported lower values of 54% and 64%. This difference can be attributed to their 24-hour measurement, which had a higher wake-to-sleep ratio compared to overnight measurements in other studies. Therefore, these accuracies reflect the generally poor performance of sleep classifiers in detecting wake. The average accuracy for 3-stage classification (wake vs. NREM vs. REM) was 69.7% (d = 3), and for 4-stage classification (wake vs. light vs. deep vs. REM), it was 65.2% (d = 9).

sheefrex··on The NIS2 Directive: A high common level of cybersecurity in the EU
I was wondering who this would apply to, and found this from another source:

"The directive covers 'essential entities' and 'important entities'.

Essential organisations will generally have a minimum of 250 employees, annual turnover of at least €50m or a balance sheet of at least €43m.

The essential sectors include energy, transport, finance, public administration, health, space, water and digital infrastructure.

Important entities will generally have a minimum of 50 employees, annual turnover of €10m or a balance sheet of €10m."

https://www.rte.ie/news/business/2024/1012/1475023-eu-cybers...

sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Yes, apparently headaches are listed as one of the possible side-effects
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Very interesting -- I often move my legs when seated and this annoys people haha

Curious to try this out now -- have never tested L-tyrosine before. I wonder what other effects it could have.

sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Quite good support for the caffeine/theanine interaction in the literature -- I was mainly trying to see if it could improve sleep which is why I didn't take it with caffeine. Would be interesting to do some blinded cognitive test at some point though to get some estimate on how much congitive performance is increased. I need to think about ways to measure that, aside from flashcards. I actually have the website connected to a chess API so that might be a nice test.
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
This is a good and fair question (although noting that the doses in the second study seem extremely large compared to supplement values). I think the solution is to test, test, and test on as many things as possible which is not being done at the moment. Most supplements will probably not have any notable effect, like L-theanine in my case, so a precautionary principle would lead one to discontinue use.
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Good to hear they seem to be working out for you. I tried L-tryptophan a few years ago but discontinued rather quickly as I thought my sleep quality was going down (I think I was waking up during dreams more often). I guess 5-HTP would have been even more powerful.
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Very interesting: maybe it could have been something else in the sodas? Alternatively, the quality of the amazon supplement might not have been great (unless you tried from multiple sources)
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Indeed, one of the studies cited supports this view.
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Yes, you are very right: this is something I will definitely add eventually.
sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
My view on this is if you don't find any effect or a tiny effect (the case here) that is already useful information. For most supplements, my bet is that you won't even benefit from a placebo effect.

And if you do find an effect, then you should do a more high-effort self-blinded test.

sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
That has a lot more L-theanine, but even then seems very variable so could be the same or way off.

For example, in one study "the final dose of 1 gram of Matcha green tea was taken on the testing day and contained only 12.4 mg of L- theanine." Source: https://www.ffhdj.com/index.php/DietarySupplementsNutraceuti...

Another study: "According to Kaneko et al., the content of l-theanine in matcha tea infusions amounts to 6.1 mg/L [50], while Unno et al. [9] found as much as 44.65 mg/g of that compound in matcha tea samples." Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7796401/

I'm not sure, but I guess one would use around 4 grams of matcha in a cup? So then at the upper bound you would come close to 200mg. But matcha has a lot of caffeine so probably not suitable to improve sleep.

sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
They're not as accurate as polysomnography but there is some correlation which should allow these measurements to serve as a useful proxy over 100-180 days. See this review for example:

"The findings of this systematic literature review indicate that the devices with higher relative agreement and sensitivities to multistate sleep (ie, Fitbit Charge 4 and WHOOP) seem appropriate for deriving suitable estimates of sleep parameters. However, analyses regarding the multistate categorization of sleep indicate that all devices can benefit from further improvement in the assessment of specific sleep stages."

Source: https://mhealth.jmir.org/2024/1/e52192/PDF

sheefrex··on Self-experiment with L-theanine: effect on sleep and cognition
Indeed, but you would really need to drink a lot of green tea to get the same amount of L-theanine you would in a supplement: "2.5 litres of brewed green tea would be needed to get 200mg of L-theanine". Also a question of how much dose you want of course...
sheefrex··on How Homogeneous Is Japan?
As far as I'm aware, France and to a lesser degree Germany also don't collect this information.

> https://www.theguardian.com/world/2020/jun/16/france-and-ger...

sheefrex··on Inequality Killed the Roman Republic
You've misinterpreted that part of the article.

The reason to avoid a monetary reward is not that it is tacky, but because money can easily be used to pass on influence to offspring, such as by boosting their profile, or buying votes for them. This can undermine a selection mechanism where they should win or gain reputation by engaging in pro-social activities.

Also, not everything may be monetised. I cannot sublet the garage attached to my apartment for example, because the contract forbids it. AirBnB is banned in some cities/situations.

sheefrex··on Inequality Killed the Roman Republic
This is the question exactly.

The difficulty is that there is a downward spiral: if fewer talented people enter the public service or politics because it is becoming relatively unattractive, the average performance of that class goes down. That makes it harder to justify any increase in salary or other benefits, reinforcing the dynamic.

sheefrex··on Inequality Killed the Roman Republic
I'm not from the US so I thread hesitantly here.

But it seems to me that there is still a lot of energy from the population at large being devoted to politics, such as with the higher turnout in the last presidential election. When that starts to decline, such as when people just can't be bothered to vote, will be the real sign they no longer have faith in politics.

I think you are right regarding creativity – but that is the case across the West it seems to me.

sheefrex··on Inequality Killed the Roman Republic
This reminds me of a part of Toynbee's framework for civilisational decline. If the leaders of a society stop being creative, they can no longer lead by inspiration and example and so need to start to dominate to retain and exert power. Maybe you could see censorship as part of that, but it's a bit early to tell for sure.

But what's more interesting is what he says comes after: in reaction to a dominant leadership, the masses withdraw their loyalty and start to devise new religious forms (or maybe repurpose old ones). So a growing religious fervour could be a sign of things going wrong. I don't think we see that yet, but it could be something to keep an eye out for if people lose faith in the power of politics to improve their situation.

sheefrex··on Inequality Killed the Roman Republic
Inequality in the Roman Republic only really started to grow after the Punic Wars, so it took around two hundred years to fully rot away the legitimacy of the system
sheefrex··on Shall the West Pass Too? Whispers from Fallen Civilisations
Thank you for the comment. I haven't read that but I will take a look!
sheefrex··on Shall the West Pass Too? Whispers from Fallen Civilisations
Thank you! Yes I agree
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