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Positive Bias Could Erode Public Trust In Science

ananyo writes "Evidence is mounting that research is riddled with positive bias. Left unchecked, the problem could erode public trust, argues Dan Sarewitz, a science policy expert, in a comment piece in Nature. The piece cites a number of findings, including a 2005 paper by John Ioannidis that was one of the first to bring the problem to light ('Why Most Published Research Findings Are False'). More recently, researchers at Amgen were able to confirm the results of only six of 53 'landmark studies' in preclinical cancer research (interesting comments on publishing methodology). While the problem has been most evident in biomedical research, Sarewitz argues that systematic error is now prevalent in 'any field that seeks to predict the behavior of complex systems — economics, ecology, environmental science, epidemiology and so on.' 'Nothing will corrode public trust more than a creeping awareness that scientists are unable to live up to the standards that they have set for themselves,' he adds. Do Slashdot readers perceive positive bias to be a problem? And if so, what practical steps can be taken to put things right?"

8 of 408 comments (clear)

  1. Feelings are more important than science by Gothmolly · · Score: 5, Insightful

    Right? isn't that what American schools and TV have been teaching for the last 30 years? Nerds aren't cool - facts are open to interpretation - everyone is special - you can eat more than you grow... When you have a society rewarding irrationality, what do you expect? Rigorous science?

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    I want to delete my account but Slashdot doesn't allow it.
    1. Re:Feelings are more important than science by AwesomeMcgee · · Score: 5, Insightful

      I wonder how many of these "positive bias" results come from the fact that if you publish results that disagree with the bias of those who are paying for the study, they'll probably ensure it's never published and you'll find yourself no longer running studies on their dollars.

      In the tech industry we all deal with non-technical managers who drive the technical direction and often times define the message to the clients. Does science suffer the same unskilled managerial types pushing scientists to interpret results in a particular way perhaps?

      I have a hard time believing a professional scientist doesn't know how to apply the scientific method, but then again incompetence is rampant in every other industry I guess, why not the scientific one..

  2. data point by Anonymous Coward · · Score: 5, Insightful

    I received my PhD in physics, and the thesis was measuring a number, in which I measured zero within the error bar. Not particularly interesting, but valid science. My wife was in a PhD program in Biology, she also did valid science, novel measurement technique, came up with an uninteresting result, therefore was not able to publish, therefore was unable to graduate. It would have been extremely simple to fudge the result to a 2-3 sigma result 'hinting' at an interesting answer, which would have gotten published. I think certain sciences have gotten to a point where they have forgotten that if you do valid work in a novel way, then that is science and you should not be punished for the conclusion of the measurement. Most measurements you do of the natural world should probably end up being unsurprising, and thus uninteresting, but you don't graduate or get tenure with those kinds of results. I think this is the mechanism for the positive bias. That is why I do not take results from certain branches of science at face value.

  3. Re:Wow! I guess Science HAS become a religion by AwesomeMcgee · · Score: 5, Insightful

    Science is a method dingbat, anyone who puts faith in a scientist however is practicing demagoguery.

    Practice science, not demagoguery.

  4. Re:Wait, what? by thegreatemu · · Score: 5, Insightful

    While I agree that models are frequently refined, leading to new results, there is a disturbing trend I see, not having to do with positive bias necessarily, but with uncertainty estimation.

    One thing that I've found incredibly hard to beat into undergrads taking my physics lab courses is that getting your uncertainties (or error bars) right is far more important than getting the right central value. This is because uncertainties are the only way that two experiments can be compared against each other, or the only way to compare experiment to theory. If I have two models of climate change, one of which predicts a temperature rise of 3 C ± 5% and another that predicts 4 C ± 7%, those results are in large disagreement, whereas two studies that predict 20 C ± 15% and 40 C plusmn 35% are in much closer agreement.

    But I see it seems much more frequently, especially in fields like astronomy, too little thought goes into the systematic uncertainties, and you'll get 4 experiments measuring the same thing with results that cannot be reconciled if you take their statistics at face value. This was a huge problem with many of the early global warming predictions as well; every year a new estimation would come out that was completely incompatible with the previous one. Yes, these models are insanely complicated, and it's damn hard to understand all the systematics. And of course you can't put in error bars for plain old mistakes. But do it too many times, and people begin to lose any faith that your estimates can be relied on for anything.

    This is the problem I see; not necessarily bias toward a positive result, but a bias toward underestimating the uncertainty of your measurement, which I suppose could be different sides of the same coin. (E.g., a result of 2 ± 0.1 is a positive result; a result of 2 ± 5 is not!).

  5. Science comes when results are confirmed by Geoffrey.landis · · Score: 5, Insightful

    Actually, science is stll working; the real trouble comes with the publicity of the science.

    You should never believe the results of any single study. Every scientist knows this; or should know this. Science comes when results are confirmed, not when somebody publishes the first paper. The real work of science just starts when somebody publishes a study saying "we show that x has the effect y." That initial paper really is no more than "here's a place to start looking." However, newspapers want to publish news, and they need to publish whatever's hot and interesting and being done today, not "well, scientist z had his team take a look at the xy phenomenon to see if there was anything interesting there, and they couldn't really find anything there, although maybe some other research lab might have different results."

    And, I suppose that somebody should post a link to the obligatory xkcd: http://xkcd.com/882/

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    http://www.geoffreylandis.com
    1. Re:Science comes when results are confirmed by rgbatduke · · Score: 5, Insightful

      Actually, you need to read "The Black Swan" by N. N. Taleb. Science that tries to confirm a theory is already infected with confirmation bias. There are a pile of examples that demonstrate the fallacy of confirmatory inference. Taleb uses a variant of Bertrand Russell's -- a turkey might reasonably infer, based on his daily experience, that humans exist for the sole purpose of feeding him, caring for him, providing for his every need. This might go on for day after day, increasing the turkey's degree of belief in his hypothesis of a good and beneficent humanity filled with love of turkeys, right up to the day that -- ulp -- something unexpected happens.

      I'm not a Popperite, rather a Jaynes-Cox-Bayesian, but nevertheless it is important to avoid confounding the relative strength of positive and negative evidence. Absence of evidence is not the same as evidence of absence, yet we almost invariably confound the two.

      Taleb damn skippy agrees with you about publicity, however, and the near-criminality of publicity and reporting of science. A newspaper necessarily takes a scientific result or observation and transforms it two ways: First of all, it creates a narrative. It isn't just "a tornado hit Houston", but "a tornado hit Houston, possibly caused by Anthropogenic Global Warming" with the subtext "this isn't an act of nature, random an unpredictable, but is instead our fault". Aztec priests couldn't have come up with a better excuse for ripping the still beating hearts out of a stream of slaves and war captives. Second, it necessarily reduces the complexity of the result to no more than three variables, ideally one. It "Platonifies" it (according to Taleb) -- wraps it up in a pretty, easy to understand package that makes it more predictable, less random than it really was. Global warming is a much simpler "cause" than "A cold front overrunning a warm wet surface layer of air near the ground, creating turbulent rolls that break off and terminate on the ground, sustained and driven by the thermal difference, and it is a better story too.

      Sadly, as you point out, real science is all too often (and should be) scientist z looked at something and didn't find much. But what they failed to find and how they looked is actually often as or more important than a study that claims to find something, especially when the latter uses questionable methodology to try to prove something, cherrypicks data (for the same purpose), ignores silent evidence (ditto) etc. Medical science is permeated with this. Nobody gets famous, or rich, or even a job, for looking for a cure for cancer and not finding one. This too is addressed by Taleb. Great book.

      rgb

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      Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
  6. Re:Wait, what? by jo_ham · · Score: 5, Insightful

    And there's jerks like you who claim that anyone who dare look askance at your work are "anti-intellectual" are are too stupid to sort out what to trust in a scientific publication (are you saying that scientific publications, Nature, et. al. have untrustworthy material in it?)

    Ah, classic twisting of my words. I'm talking about anti-intellectualism as a movement. Those doing it are extremely smart - that's what makes them good at it. They're good at duping people into following their cause. I am not personally calling individual people stupid unless they actually demonstrate that they are.

    And yes, I'm absolutely saying that scientific publications contain untrustworthy information, including the big hitters like Science and Nature - their size and prestige is no assurance of infallibility, and in fact can work against them since people are often reluctant to question them. That's the nature of scientific publishing - until results have been replicated, single-source experiments and models need to be looked at with extreme skepticism.

    Last year I performed some work that disproved a piece of published literature (in a non-controversial area of chemistry). I didn't set out to disprove it - I set out to see if I could replicate the results and I determined that the published paper was incorrect. My own conclusions, method and data set were published in response, with some discussion on why the previous paper was drawing incorrect conclusions (mainly an issue with experimental control). My situation is one that is repeated constantly - it's how science works. The stuff that can't be replicated is corrected, the stuff that is replicated becomes more solid.

    It's not the layman's fault that they don;t understand some of the intricacies of how peer review and scientific publishing and research works. They're not stupid for not getting that in the same way that I'm not stupid for not understanding the first thing about programming - it's simply not my area of expertise. Where the stupidity *does* arise, however, is when people start to distrust scientists out of hand because they're being told to do so by certain media outlets or special interests. It happened with vaccinations due to a corrupt doctor manipulating a very weak study with the ultimate aim to push a competing vaccine made by a company that paid him off, but it backfired spectacularly - far from getting the competing vaccine popular, people rejected vaccination entirely against their own interests, putting their own and everyone else's kids at more risk. It's this sort of media frenzy and associated public panic and distrust of science (even now, people refuse to believe scientists on the issue, despite the original study being totally debunked and Wakefield himself being struck off the medical register et and the whole thing exposed as a sham).

    That's the sort of thing I'm talking about here. We saw it with the MMR vaccine, we see it with nuclear power, we see it with stem cell research, we see it with GM foods (and there *are* some legitimate issues to be raised there, being drowned out by typical media hysteria), we see it with climate science - again, there are legitimate issues to be raised and discussed on a topic that is *gigantic* in scope in the scientific community, but it's being drowned in so much media hysteria and political propaganda that it's almost impossible to get anything done.

    Of course, equating people who don't drink your Kool Aid to those who deny the Holocaust really helps your cause to be seen as our nights in shining armor.

    Where did I say that? You're dangerously close to Godwining the thread by trying to imply that I brought that up when I did no such thing. The hyperbole serves no one, it only makes your arguments look weak.

    I'm not looking to be anyone's "night [sic] in shining armor", nor are most scientists. We just work on the science in our field and go where that leads us. If we wanted to be knights rescuing people I'd have joined the fire service or something. I became a scientist to ultimately help mankind and further our collective knowledge, but I'm no superhero or white knight.