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Most scientists 'can't replicate studies by their peers'

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Re: Most scientists 'can't replicate studies by their peers'

#231

Direct replication is a waste of time. Move forward, later when there is better technology/data, it will either agree or disagree.

Direct replication can be very important, at least in math and the hard sciences.

In physics labs, students conduct experiments that once warranted a Nobel prize. And some of the problem sets that physics grad students work on repeats work that once won a Nobel prize.

When I was in physics grad school, a scandal erupted when Jan Hendrik Schön's "breakthroughs" results on semiconductor nanostructures couldn't be replicated. [1] He'd received a fair bit of acclaim, had one a couple of prizes, and I heard there was even Nobel buzz for him. His papers were in Science, Nature, and Phys. Rev. Letters. Several groups tried and failed over and over to confirm his breakthroughs. It turned out that he had falsified data. 28 of his journal articles were retracted by the publishers and others are still considered suspect.

When a theory or experiment comes along that generates the kind of excitement and interest that can lead to new technology or prestigious grants and awards, replication is important. Science stands on the shoulders of what has come before. We need to know that we're building on a solid foundation.

[1] https://en.wikipedia.org/wiki/Schön_scandal

Re: Most scientists 'can't replicate studies by their peers'

#232
post #227

Earlier quoted context omitted.

I think there's also a lot of confusion about what the scientific literature should be. Outsiders think of journals as pre-packaged nuggets of science fact, with conclusions that you can read and trust. Scientists who publish in the journals view them as a way to communicate a body of work of "I did this, here is the result I saw. I think it might mean this." The difference between these two views can not be understa…

Scientists and academic institutions add to the confusion with the way they promote their work. Nobody puts language like "I did this, here is the result I saw. I think it might mean this" in a press release. It's always "Breakthrough research! Is the end of cancer in sight??"

A lot of this is because of the incentives that result from grant-based funding of science. Your ability to continue to do science is contingent on your ability to find someone to pay for it; it's much easier to convince someone to pay for it if you can point to headlines that say "Breakthrough research! Is the end of cancer in sight?"

The old system of "gentleman science" (where only independently-wealthy heirs did science, as a hobby) had a lot of problems and wouldn't really be workable today, but one thing it had going for it was that the scientist could count on the funding being there tomorrow, and so had much less of an incentive to overstate their work.

Re: Most scientists 'can't replicate studies by their peers'

#233
post #28

"all you have to do is read the methods section in the paper and follow the instructions." I wish science was that simple. The methods section only contains variables the authors think worth controlling, and in reality you never know, and the authors never know. Secondly, I wish people say: "I replicated the methods and got a solid negative result" instead of "I can't replicate this experiment". Because most of the t…

I'm surprised no one mentioned the company Mousera (http://www.vium.com/). Granted, it is not a solution for all of science, but it essentially brings down many animal experiments to scripts, which can be run almost like I might run a docker container and script. The idea is incredible. You can even scale it up by running the script multiple times.

Disclaimer: I did bench and animal work 21yrs ago during undergrad, but havent used this company. So I know the field and how difficult replication is, but i'm not sure what has happened in wet science since 1997.

Re: Most scientists 'can't replicate studies by their peers'

#234
post #219

Earlier quoted context omitted.

>The good news is that you can't really fake proofs or formal analysis. It's my understanding that most published mathematical proofs aren't "hey look at this theorem in first order logic that we reduced to symbol manipulation"; rather, they present enough evidence that other mathematicians are convinced that such a proof could be constructed. Is that incorrect?

I'm not a mathematician, but I had a math prof tell me that most publications only contain proof sketches, not full proofs. Can someone in the field comment?

I work as an applied mathematician. In general, I would say that this is incorrect. Virtually all of the papers that I read I would contend have full proofs. That said, I can sympathize with the sentiment in a certain sense.

Just because a paper contains a proof doesn't mean that the proof is correct nor that it's comprehensible. Further, even if a paper went through peer review, it doesn't mean that it was actually reviewed. I'll break each of these down.

First, a proof is just an argument that an assertion is true or false. Just like with day to day language, there are good arguments and bad arguments. Theoretically, math contains an agreed upon set of notation and norms to make its language more precise, but most people don't abide by this. Simply, very, very few papers use the kind of notation that's read by proof assistant tools like Coq. This is the kind of metalanguage really required for that precise. Now, on top of the good and bad argument contention, I would also argue that there's a kind of culture and arrogance associated with how the community writes proofs. Some years back, I had a coauthor screaming at me in his office because I insisted that every line in a sequence of algebraic reductions remain in the paper with labels. His contention was that it was condescending to him and the readers to have these reductions. My contention was that I, as the author of the proof, couldn't figure out what was going on without them and if I couldn't figure it out with all those details that I sincerely doubt the readers could either. Around the office, there was a fair amount of support for my coauthor and removing details of the proof. This gives an idea of the kind of people in the community. For the record, the reductions remained in the submitted and published paper. Now, say we removed all of these steps. Did we still have a full proof? Technically yes, but I would call it hateful because it would require a hateful amount of work by the readers to figure out what was going on.

Second, peer review is tricky and often incredibly biased. Every math journal I've seen asks the authors to submit to a single blind review meaning that the authors don't know their reviewers, but the reviewers know the authors. If you are well known and well liked in the field, you will receive the benefit of the doubt if not a complete pass on submitted work. I've seen editors call and scream at reviewers who gave "famous" people bad reviews. I feel like I was blacklisted from one community because I rejected a paper from another "famous" person who tried to republish one of their previous papers almost verbatim. In short, there's a huge amount of politics that goes into the review process. Further, depending on the journal, sometimes papers are not reviewed at all. Sometimes, when you see the words "communicated by so-and-so" it means that so-and-so vouched for the authenticity of the paper, so it was immediately accepted for publication without review. Again, it varies and this is not universal, but it exists.

What can be done? I think two things could be done immediately and would have a positive affect. First, all reviews should be double blind, including to the editor. Meaning, there is absolutely no good reason why the editor or the reviewers should know who wrote the paper. Yes, they may be able to figure it out, but beyond that names should be stripped prior to review and readded only at publication. Second, arbitrary page limits should be removed. No, we don't need rambling papers. If a paper is rambling it should be rejected as rambling. However, it removes one incentive to produce difficult to follow proofs since now all details can remain. Virtually all papers are published electronically. Page counts don't matter.

In the long run, I support the continued development of proof assistant tools like Coq and Isabelle. At the moment, I find them incredibly difficult to use and I have no idea how I'd use them to prove anything in my field, but someday that may change. At that point, we can remove much of the imprecision that reviewers introduce into the process.

Re: Most scientists 'can't replicate studies by their peers'

#235

This is ego, politics and career ambitions undermining modern science. Unfortunately, the fact that this is occurring so rampantly will bolster anti-intellectuals and give them a very potent argument to point to when presented with facts. This is a systemic failure of basic ethics that will hurt us all. The success-at-all-cost career mindset is toxic in all tracks, but this is one of the most dangerous for it to take…

> Unfortunately, the fact that this is occurring so rampantly will bolster anti-intellectuals and give them a very potent argument to point to when presented with facts. Shouldn't you be just as well happy that these "anti-intellectuals" are pointing out flaws in something you thought was true?

Broken clocks are still right twice a day.

Re: Most scientists 'can't replicate studies by their peers'

#236
post #78

Earlier quoted context omitted.

> The methods section only contains variables the authors think worth controlling, and in reality you never know, and the authors never know Maybe the format needs to change. Perhaps journals should require video, audio commentary or automated note taking for publication.

I was chatting with a colleague last summer, and asking him for more details about a method he had published that I was having trouble reproducing. After pointing me to a few papers that didn't include the relevant details, hefinally told me that "if we told everyone about how it was done, anyone could do it." While at the time I was pretty upset with him, perhaps it's the competitive nature of science and funding th…

Code/design/engineer are considerably different than say biology, because you can (and should) publish artefacts. The actual code/algorithms (not pseudo code) needs to be shared and archived with the journal.

There has been some work for archiving code with some journals and some allow video uploads as well for segments from the actual experiments.

Re: Most scientists 'can't replicate studies by their peers'

#237
post #58

Earlier quoted context omitted.

> The methods section only contains variables the authors think worth controlling, and in reality you never know, and the authors never know Maybe the format needs to change. Perhaps journals should require video, audio commentary or automated note taking for publication.

> Maybe the format needs to change. Perhaps journals should require video, audio commentary or automated note taking for publication. A 'world view' column in Nature suggested the same things last week [1]; the author described a paper of theirs [2]: > Yes, visual evidence can be faked, but a few simple safeguards should be enough to prevent that. Take a typical experiment in my field: using a tank of flowing water t…

I thought some journals were now allowed video archives. Some of the most famous experiments, such as the Stanley Milgram studies, have excellent video documentation (and in the case of Milgram, it's been replicated all around the world .. although no it's not ethical to do so).

Re: Most scientists 'can't replicate studies by their peers'

#238
post #148

Earlier quoted context omitted.

Actually, reproducibility is not considered a necessity in science. It is factually false to say that a person who carries out an experiment in good faith and shares their methods and results is not scientific- they just aren't satisfying a criterion which is a good thing to have. It's pretty clear what's different between my paper and a Uri Geller experiment. If you can't see the difference, you're either being obst…

> Actually, reproducibility is not considered a necessity in science. By whom? I think you're using as a premise the very matter that is being discussed.

I would say that most scientists, at the top of their game, who have years of trusted publications behind them, should be given some latitude to publish discovery science without the requirement of reproducibility, so long as they share their results in detail, and accept postdocs who then take the resulting research materials to their new labs.

I didn't always believe this, but after spending a bunch of time reading about the numerous times in history when one scientist discovered something, published the results, and were told they were wrong because other people couldn't reproduce their results, only to be shown correct when everybody else improved their methodology (McClintock, Cech, Boyle, Bissell etc).

This ultimately came to a head when some folks critized the lack of repeatability of Mina Bissel's experiments (for those who don't know, she almost singlehandledly created the modern understanding of the extracellular matrix's role in cancer).

She wrote this response, which I originally threw on the floor. http://www.nature.com/news/reproducibility-the-risks-of-the-... After rereading it a few times, and thinking back on my experience, I changed my mind. In fact, Dr Bissel's opinion is shared by nearly every top scientist I worked with at UCSC, UCSF, and UC Berkeley. The reason her opinion has value is that she's proved time again that she can run an experiment in her lab that nobody else in the world is capable of doing, and she takes external postdocs, teaches them how to replicate, and sends them off to the world. In other cases, she debugged other lab's problems for them (a time consuming effort) until they could properly reproduce.

I believe reproducibility is an aspirational goal, but not really a requirement, for really good scientists, in fields where reproduction is extremely hard.

Re: Most scientists 'can't replicate studies by their peers'

#239

So I can't be the only one who has noticed the correlation between this and the field at question. As soft sciences like soc, psych, and medicine seem to have the most problems with it. I'm not saying hard sciences like physics don't, but it is less common. The math for the soft sciences isn't as concrete and doesn't provide a good foundation. I think there are also major problems with the use of p values. It is too…

Soft sciences actually dont have a greater problem with replication. It is just more publicized, in part because those researchers are actually addressing the problem and making large scale replication attempts.

Well that depends. What kind of reproducibility are you talking about? If we talk about something like Higgs then it was definitely reproduced. Same with gravitational waves.

But the other problem is that the soft sciences have a compounding problem. The one I mentioned about the foundation not being as strong. As a comparison psychology needs a p=0.05 to publish. Particle physicists need 0.003 for evidence and 0.0000003 for "discovery". But the big difference is the later are working off of mathematical models that predict behaviours and you are comparing to these. You are operating in completely different search spaces. The math of the hard sciences allows you to reduce this search space substantially while the soft sciences still don't have this advantage. But give them time and they'll get to it. The math is difficult. Which really makes them hard to compare. They have different ways of doing things.

Re: Most scientists 'can't replicate studies by their peers'

#240
post #111
post #90

Earlier quoted context omitted.

> I was chatting with a colleague last summer, and asking > him for more details about a method he had published that > I was having trouble reproducing. After pointing me to a > few papers that didn't include the relevant details, > hefinally told me that "if we told everyone about how it > was done, anyone could do it." That's not science, that's bullshit. Can you please expose that? Scientists shouldn't simply get…

That is exactly how science works. Methods sections include just enough information to get a good sense of how the experiment was done, not enough information to replicate it exactly. Some disciplines are worse than others. People could also publish plain text data as supplementary material, but why do that when you can get away with a raster image of a plot...

That's an absurd degree of cynicism. I just finished my PhD in chemical engineering, and I did the reverse of this. In fact, I successfully migrated the younger members of my research group to a completely open-source software stack for chemical simulations, so that in principle anyone with a Linux box could reproduce our results. We published all our code and plain text versions of the data.

I'm not saying you're wrong about the incentives - scientists are often incentivized toward secrecy - but I deny that we have to follow such incentives.

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