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The Irreproducibility Crisis of Modern Science

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Re: The Irreproducibility Crisis of Modern Science

#181
post #68

The site is down so I can't read the original report, but I've read reports on this topic in the past so I'm going to chime in with some "usual suspects" caveats: 1. No result is 100% reproducible because you can never completely reproduce the conditions of any experiment. The best you can hope to do is to reproduce the conditions that matter , but enumerating those has to be part of the theory you are testing, and s…

Power is also a concern that many researchers do not pay attention to (at least in psychology/neuroscience).

If the original study was under-powered, the estimated effect size in that study will be inflated and any replication attempt that uses this inflated effect size estimate will be severely underpowered.

Plus, two independently conducted studies that are both powered at 80% to detect a true effect will both be positive results only 64% of the time (assuming absolutely nothing fishy going on, e.g. p-hacking).

Re: The Irreproducibility Crisis of Modern Science

#182
post #68

The site is down so I can't read the original report, but I've read reports on this topic in the past so I'm going to chime in with some "usual suspects" caveats: 1. No result is 100% reproducible because you can never completely reproduce the conditions of any experiment. The best you can hope to do is to reproduce the conditions that matter , but enumerating those has to be part of the theory you are testing, and s…

> 1. No result is 100% reproducible because you can never completely reproduce the conditions of any experiment.

This is why you include the error in your results. We don't care if your two experiments result in 100% the same results. We care about if your results line up within the error of your experiment.

> 2. Even a completely non-reproducible result can be scientifically significant. For example, celestial events are almost never reproducible. Our understanding of celestial mechanics nonetheless rests on solid science.

This is why we share data. That is in essence our observation. A celestial event might be caught by only one instrument, but several people can develop several different models. We wait and watch for similar events though, to check if models are consistent (within error).

> 3. The end-product of science is not truth, it is explanations of observations.

I just wanted to repeat this because it can never be stated enough.

> 4. The statistical tests currently in widespread use as a criterion for publication in peer-reviewed journals guarantee that at least one result in 20 will be due to chance and not because the hypothesis being tested is actually true.

While I don't like p values, because of hacking, (especially 0.05) that's not how stats work. Flipping 10 heads doesn't guarantee 5 tails, not even 1. I wouldn't use as strong as a word as guarantee.

But this is also an argument FOR reproducing. If multiple experiments are consistent with one another (within error) than that strengthens the argument.

TLDR: More brains that look at a problem helps solve the problem.

I will add my own statements about the reproducability problem in science. One is because there is less funding for it. Reproducing an experiment isn't sexy. Another problem just stems from that data isn't always open. It is hard to review work if you don't know everything about the experiment. Data can even have simple mistakes that just weren't caught. But it is also embarrassing to share data.

Re: The Irreproducibility Crisis of Modern Science

#183
post #149
post #73

What I'd like to know is if the "irreproducibility crisis" is really some combination of "sample size was too small" and "effect size was too small". When I went through a lot of these studies myself and saw the ones that don't reproduce, I saw this theme over and over. "P-hacking" is less of a concern to me when the effect is real and widespread. It's so bad now that for any article/study, I look at the sample size…

Huge sample studies with high stat significance can have very low effect sizes, though. If an effect is shown on a small sample, it means it is a really big effect, and will likely be reproduced in a bigger study.

It's a combination of sample size and effect size. The larger one is, the more I'm willing to give on the other.

Re: The Irreproducibility Crisis of Modern Science

#184
post #12

Earlier quoted context omitted.

If we don't use science to make decisions, what are we supposed to use? Gut instinct? Of course science is imperfect, but it tends towards truth over time, whereas dogma and populism have no way of correcting mistakes that isn't just as likely to introduce new ones.

How long ago was it that science was controverting centuries of populist knowledge that carbs are what made you fat, not eating fat? Talk about science creating a mind boggling ongoing health crisis by telling people to limit their fat intake and replace it with cereals and bread.

> How long ago was it that science was controverting centuries of populist knowledge that carbs are what made you fat, not eating fat?

I've looked into that and all I can say is the history is disputed - some people say there really was a nutritionist consensus, others that this was a popular misunderstanding based on overzealous popularisation of a small number of papers (similar to the myth that the consensus among climate scientists in the '70s predicted an ice age) and that working scientists never thought this.

Either way it's a failing of the process, but the appropriate response is quite different; in the first case all we can say is mistakes do happen, in the second we need to get better at ensuring that the real scientific consensus gets translated into appropriate policy actions.

Re: The Irreproducibility Crisis of Modern Science

#185
post #12

Earlier quoted context omitted.

If we don't use science to make decisions, what are we supposed to use? Gut instinct? Of course science is imperfect, but it tends towards truth over time, whereas dogma and populism have no way of correcting mistakes that isn't just as likely to introduce new ones.

> If we don't use science to make decisions, what are we supposed to use? Gut instinct? I thought the parent comment made it clear: the alternative we are supposed to use is "democracy". That is, the people who are ruled should determine the rules that are imposed on them. Now, democracy does not preclude the use of science to make decisions. The voters may rely on science to inform their decisions (when the science…

> In those conditions, the goal should be to minimize the consequences of being wrong. We do that by decentralizing decisions to the greater extent possible.

In some cases yes. In others this doesn't seem to be the case - e.g. decentralised housing/planning/zoning policy seems to have lead to worse outcomes than more centralised approaches.

Re: The Irreproducibility Crisis of Modern Science

#186

Lets take a page from Marx. Science is many things, in particular a relationship between capital and labor. The scientific method is a wonderful idea, but it is subordinate to the economic forces that underlie scientific activity. Look at the conflicts and contradictions between those doing science (labor) and those deciding the science to be done (capital), and that is the ultimate source of these crises. The execut…

Marx!? Marx can teach us very little about economics and almost nothing about science. Science is NOT “a relationship between capital and labor”.

If you see everything through a such a strong lens, you see very little.

Re: The Irreproducibility Crisis of Modern Science

#187

Earlier quoted context omitted.

I cannot speak for the person you are responding to, but in my [agreement] of his critique of statistics, I am implicitly speaking of social statistics. I think there is a vast difference in e.g. a statistical modeling of the behavior of electrons and e.g. the statistical modeling of some sort of human behavior.

...but that just isn't true. Statistical analysis is (among other things) a way to quantify our uncertainty. If done approriately, the statistics simply communicate the role probability played in moving from the experimental premises to the results. The level of uncertainty in most (perhaps all) experiments involving particles in a vacuum is far lower than experiments involving human behavior. Statistics doesn't crea…

[deleted]

Re: The Irreproducibility Crisis of Modern Science

#188
post #63

Earlier quoted context omitted.

> Instead of arguing over whether and how much the government should be imposing sin taxes on fats (and what kind of fats?) or sugars (and what kind of sugars), the better approach would be to do nothing and let people make their own choices based on the best information available to them at the time. Why? Do we believe that individuals are likely to be better informed than governments? (why?) Uncertainty is a fact o…

The history of government attempts to get people to eat "healthily" is a pretty good illustration of the many ways that government policy is a bad tool for addressing these type of issues. Government policy tends to have a lot of inertia and is bad at adapting to changing information. This is particularly evident when it attempts to track evolving scientific understanding of complex topics like nutrition and diet and…

> I certainly believe that some individuals will be better informed and better able to translate that information into the best course of action for themselves given their goals than governments, especially "governments" as represented by a patchwork of laws and regulations the impact a complex thing like individual health.

Some individuals, sure. Most individuals, probably not.

I agree that government policy has inertia, and that overconfidence on uncertain issues can lead to imposing well-intentioned policy that ends up being harmful. But it's equally possible to make the opposite mistake, and hold off introducing policy changes for too long because of perceived uncertainty. E.g. car seatbelt laws and tobacco advertising laws should have been introduced earlier than they were. I don't think there's any general principle we can draw here; some government policymakers could do with more humility, others could do with more confidence, but all any one of them can do "from the inside" is try to figure out how strong the evidence actually is on a given issue, and use their own best judgement in determining whether there's a clear enough scientific/medical consensus to warrant policy changes, or not.

Re: The Irreproducibility Crisis of Modern Science

#190

Some of the comments miss an important distinction.. Science in the popular press, often refers to science versus completely non-science ways of forming an opinion or deciding policy. Meanwhile, science within a technical community, is subject to human error and manipulation, and relies on a reproducible result, as well as peer-review, to find answers to conflicting claims. There are certainly non-Science ways of for…

Never mind the massive debate that occurs within the scientific community itself on some new or controversial claims. When the press gets its hands on the views of one dissenter and one proponent, it makes it seem like there are only sides A and B. This is not as simplistic as politics, where politicians form into immutable groups Left vs Right. We are dealing with numerous camps, and within each scientific camp, there are numerous arguments made for/against an issue.

Take climate change, no doubt a controversial issue. To say it is "controversial" in the political sense would mean Left and Right (in the USA alone) have vociferously different stances on the issue. However, if viewed as a scientific controversy, we are now talking about detailed methodological concerns, like methods of data collection, analysis, kinds of statistical bias, and subtle changes in arbitrary parameters. Any scientist can tweak this or that in their model to make it conform more easily to their preconceived notions about climate change. Unfortunately, we also have some oil industry shills out there who got trotted out as an equally weighted side B to the side A of the dozens of scientists who would generally disagree. Then, you also have anti-science proponents who use the legitimate self-criticism of scientists to attack science as a whole.

It's a sad state of affairs. Science should be reported in the press, but it should also be reported much better than it is. In the USA in particular, STEM education is lagging behind: the average person can't delineate the good science coverage from the bad, and we have ridiculous notions and conspiracies that fail to become filtered out (anti vax, climate change deniers, flat earthers, moon landing was faked, etc.)

For me, reproducibility is one problem in a broader ecosystem of scientific problems, including science education generally, as well as misuse of statistics, and a saddening drive for incremental results at the expense of more broad-based thinking which might lead to fundamental breakthroughs. Our education systems must be reformed to deal with these problems, that's the only way out that I see.

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