Trade Policy: Media queries are a great tool for changing a website’s layout depending on parameters like viewport width, but it can be very annoying when browsers do not do the same thing. An obvious example is whether or not a vertical scrollbar, should one exist, is included when the viewport’s width is calculated. It’s a question that arises with virtually every major new finding in science or medicine: What makes a result reliable enough to be taken seriously? The answer has to do with statistical significance — but also with judgments about what standards make sense in a given situation.The unit of measurement usually given when talking about statistical significance is the standard deviation, expressed with the lowercase Greek letter sigma (σ). The term refers to the amount of variability in a given set of data: whether the data points are all clustered together, or very spread out.In many situations, the results of an experiment follow what is called a “normal distribution.” For example, if you flip a coin 100 times and count how many times it comes up heads, the average result will be 50. But if you do this test 100 times, most of the results will be close to 50, but not exactly. You’ll get almost as many cases with 49, or 51. You’ll get quite a few 45s or 55s, but almost no 20s or 80s. If you plot your 100 tests on a graph, you’ll get a well-known shape called a bell curve that’s highest in the middle and tapers off on either side. That is a normal distribution.The deviation is how far a given data point is from the average. In the coin example, a result of 47 has a deviation of three from the average (or “mean”) value of 50. The standard deviation is just the square root of the average of all the squared deviations. One standard deviation, or one sigma, plotted above or below the average value on that normal distribution curve, would define a region that includes 68 percent of all the data points. Two sigmas above or below would include about 95 percent of the data, and three sigmas would include 99.7 percent.So, when is a particular data point — or research result — considered significant? The standard deviation can provide a yardstick: If a data point is a few standard deviations away from the model being tested, this is strong evidence that the data point is not consistent with that model. However, how to use this yardstick depends on the situation. John Tsitsiklis, the Clarence J. Lebel Professor of Electrical Engineering at MIT, who teaches the course Fundamentals of Probability, says, “Statistics is an art, with a lot of room for creativity and mistakes.” Part of the art comes down to deciding what measures make sense for a given setting.For example, if you’re taking a poll on how people plan to vote in an election, the accepted convention is that two standard deviations above or below the average, which gives a 95 percent confidence level, is reasonable. That two-sigma interval is what pollsters mean when they state the “margin of sampling error,” such as 3 percent, in their findings. That means if you asked an entire population a survey question and got a certain answer, and then asked the same question to a random group of 1,000 people, there is a 95 percent chance that the second group’s results would fall within two-sigma from the first result. If a poll found that 55 percent of the entire population favors candidate A, then 95 percent of the time, a second poll’s result would be somewhere between 52 and 58 percent.Of course, that also means that 5 percent of the time, the result would be outside the two-sigma range. That much uncertainty is fine for an opinion poll, but maybe not for the result of a crucial experiment challenging scientists’ understanding of an important phenomenon — such as last fall’s announcement of a possible detection of neutrinos moving faster than the speed of light in an experiment at the European Center for Nuclear Research, known as CERN.Six sigmas can still be wrongTechnically, the results of that experiment had a very high level of confidence: six sigma. In most cases, a five-sigma result is considered the gold standard for significance, corresponding to about a one-in-a-million chance that the findings are just a result of random variations; six sigma translates to one chance in a half-billion that the result is a random fluke. (A popular business-management strategy called “Six Sigma” derives from this term, and is based on instituting rigorous quality-control procedures to reduce waste.)But in that CERN experiment, which had the potential to overturn a century’s worth of accepted physics that has been confirmed in thousands of different kinds of tests, that’s still not nearly good enough. For one thing, it assumes that the researchers have done the analysis correctly and haven’t overlooked some systematic source of error. And because the result was so unexpected and so revolutionary, that’s exactly what most physicists think happened — some undetected source of error.Interestingly, a different set of results from the same CERN particle accelerator were interpreted quite differently. A possible detection of something called a Higgs boson — a theorized subatomic particle that would help to explain why particles weigh something rather than nothing — was also announced last year. That result had only a 2.3sigma confidence level, corresponding to about one chance in 50 that the result was a random error (98 percent confidence level). Yet because it fits what is expected based on current physics, most physicists think the result is likely to be correct, despite its much lower statistical confidence level.Significant but spuriousBut it gets more complicated in other areas. “Where this business gets really tricky is in social science and medical science,” Tsitsiklis says. For example, a widely cited 2005 paper in the journal Public Library of Science — titled “Why most published research findings are wrong” — gave a detailed analysis of forex growth bot of factors that could lead to unjustified conclusions. However, these are not accounted for in the typical statistical measures used, including “statistical significance.”The paper points out that by looking at large datasets in enough different ways, it is easy to find examples that pass the usual criteria for statistical significance, even though they are really just random variations. Remember the example about a poll, where one time out of 20 a result will just randomly fall outside those “significance” boundaries? Well, even with a five-sigma significance level, if a computer scours through millions of possibilities, then some totally random patterns will be discovered that meet those criteria. When that happens, “you don’t publish the ones that don’t pass” the significance test, Tsitsiklis says, but some random correlations will give the appearance of being real findings — “so you end up just publishing the flukes.”One example of that: Many published papers in the last decade have claimed significant correlations between certain kinds of behaviors or thought processes and brain images captured by magnetic resonance imaging, or MRI. But sometimes these tests can find apparent correlations that are just the results of natural fluctuations, or “noise,” in the system. One researcher in 2009 duplicated one such experiment, on the recognition of facial expressions, only instead of human subjects he scanned a dead fish — and found “significant” results. “If you look in enough places, you can get a ‘dead fish’ result,” Tsitsiklis says. Conversely, in many cases a result with low statistical significance can nevertheless “tell you something is worth investigating,” he says.So bear in mind, just because something meets an accepted definition of “significance,” that doesn’t necessarily make it significant. It all depends on the context.WASHINGTON -- The Federal Aviation Administration unveiled a plan Monday for reducing the accident rate for private and corporate aircraft by 10 percent by the year 2018. Shinmoedake, on Japan's Kyushu Island, has been erupting off and on since Jan. 26, and its lava dome has grown dramatically. A photo from Feb. 4 shows the lava nearly filling the volcano's crater, which is about 2,300 feet wide. Scientists are predicting that eruptions could grow stronger and go ... One is a scruffy rabble-rouser, the other is a clean-shaven Islamist, but they are united in their fight against Libyan leader Moammar Gaddafi. The Mets seek a second team to share their spring training facility in Port St. Lucie, Florida, because it would generate more revenue and ensure another team does not depart the region. The Oklahoma City Thunder were unhappy about coming back to Houston for Game 6. They left town in a much better mood.     DALLAS - Chip maker Texas Instruments Inc. said Monday that "substantial" damage to one of its major manufacturing plants near Tokyo in last week's earthquake will result in extra costs and lost revenue in the first half of this year. The space agency's rush to capture an asteroid for its astronauts can only lead to no good, critics argue at workshop How opponents of NASA background checks unwittingly became campaigners for workplace data privacy and security. QATIF, SAUDI ARABIA - A "Day of Rage" planned by critics of the Saudi Arabian government proved relatively calm Friday, with peaceful demonstrations in and around the eastern city of Qatif, a day after police fired on protesters there, and elsewhere in oil-rich Eastern province. Sarah McCarthy has a peculiar passion for a 16-year-old: She's a vinyl junkie. You know it's love when it survives a shared 700-square-foot condominium -- with a single bedroom closet. When it inspires you to sell your first home at a loss. When you agree to delay moving in for more than a year after your wedding so your stepdaughter can finish high school. The first generation to exercise is getting an unwanted message from its knees: slow down. The problem may be your genes. Carbone in Greenwich Village looks to summon up a spirit of 1950s, big-meatball abundance. BAGHDAD — More than 40 people were reported killed in fighting in a key city in northern Iraq and gunmen took over a town elsewhere in the country Thursday, raising concerns that unrest roiling Sunni areas is spreading. Iraq’s prime minister appealed for calm following three days of violence that has left more than 150 dead. Read full article >>     Hundreds of thousands of Venezuelans were on the streets again on Friday at a funeral parade for Hugo Chavez amid opposition protests that the government was exploiting his death for election purposes. Microbiologists who study wild marine microbes, as opposed to the lab-grown variety, face enormous challenges in getting a clear picture of the daily activities of their subjects. But a team of scientists from MIT and the Monterey Bay Aquarium Research Institute recently figured out how to make the equivalent of a nature film, showing the simultaneous activities of many coexisting species in their native habitat over time. Instead of making a movie, the scientists used a robotic device that dangled below the surface of the ocean, drifting in the water with a neighborhood of microbial populations and gathering samples of one billion microbes every four hours. Similar to fast photography that stops action, the robotic device “fixed” each sample so that whatever genes the microbes were expressing at the moment of capture were preserved for later study in the lab, where the scientists used whole-genome gene-expression analysis to create a time-lapse montage of the daily labors of multiple microbial species over a two-day period. “A naturalist like Sir David Attenborough can follow a herd of elk and see how the elk’s behavior changes hour to hour, day to day and week to week. But we haven’t been able to observe naturally occurring microbes with that kind of resolution until now,” says Edward DeLong, the Morton and Claire Goulder Family Professor in Environmental Systems in the MIT Department of Civil and Environmental Engineering and Department of Biological Engineering. DeLong is senior author of a paper on the study appearing online tinnitus miracle of Jan. 21 in the Proceedings of the National Academy of Sciences. Co-authors on the paper are Elizabeth Ottesen, a former MIT postdoc who is now an assistant professor at the University of Georgia; MIT postdoc Curtis Young and research engineer John Eppley; and senior research specialist John Ryan, senior scientist Francisco Chavez, and president Christopher Scholin of the Monterey Bay Aquarium Research Institute. Bucks readers discuss whether their credit scores have been hurt by medical bills.     Gediminas Urbonas, the Mitsui Career Development Associate Professor in Contemporary Technology Photo: Allegra Boverman The Football Association (FA) said on Friday it had become aware of suspicious betting on English sixth-tier matches and has called for those with information to come forward. By not being part of a mission group, Keele University can shape its own identity and avoid group politics, says Nick FoskettAs vice-chancellor of a British university, I recognise how vital it is for universities to support one another during a time of extensive reform in the higher education sector. Yet one question I am regularly asked is: why is Keele University not aligned to a mission group and never has been?With mounting pressure on universities to lead the growth of our knowledge economy, it continues to surprise many of my contemporaries that being part of a mission group is a move Keele regularly considers, but has not yet been persuaded to undertake.The simplest answer is that none of the existing mission groups provide a natural fit for Keele, a university founded on a principle to break away from established patterns. Keele is not unique in this respect, as a significant number of universities choose to be non-aligned, a fact frequently overlooked in the media and political engagement with the sector.In an article for the Guardian earlier this year, Peter Scott surmised that universities are always going to be "more different and individual" than the identity they share with their mission group, and this is one of my main concerns with group alignment.Yes, mission groups aim to highlight diversity in the sector, encourage collaboration and stimulate debate – the Russell Group provides the prevailing example of how a group can rally strength in numbers to create a powerful voice to stimulate change. Yet for me, being aligned brings with it greater risks of marginalising a university's own interests for the benefit of the wider group, which cannot be ignored.Firstly, the very nature of group politics means that each group has clearly defined parameters, usually controlled by two or three dominant universities and voiced by just a handful of spokespeople. Doesn't alignment to a group come with an added pressure to pursue and conform to an agreed agenda, potentially sidelining your institution's interests and concerns? – particularly when these interests either aren't a priority for the group, or worse still, are not shared by the group at all.Secondly, we need to consider the strong public identity of each group, and the impact of this on its members. We see time and again how MPs, parents, students and the media find mission group "identities" helpful to their own analysis. The group identity aids in the compartmentalisation of what its members stand for and each university becomes inextricably associated with its group colleagues and their latest campaigns, successes and failures. While there are undoubtedly some benefits to be had by this association, for me they are surpassed by the risk of being overshadowed, outshone and, in some cases, tarred by the overarching interests of the group, potentially causing lack of understanding about a university's offering and dampening its wider profile.Most importantly for me, are the negative effects of alignment on innovation in the sector as a whole. Arguably, it discourages competition between universities aligned to the same group and creates a hierarchy where research funding and investment are more likely to be granted to universities in the Russell Group because of its collective success and powerful presence, as opposed to universities in other groups, which have an outstanding track record of developing world-leading research within smaller institutions.So is Keele non-aligned simply because of the negative aspects of mission-groups? No. In my three years as vice-chancellor, I have found a number of positive reasons for Keele's standalone approach. Clearly, it helps Keele to define its own identity and interests without conforming to an overarching body, but what's more, it means we are viewed as more of a neutral, non-partisan university. I have found that senior colleagues are more likely to be invited to sit on thinktanks and committees to discuss issues in the sector and voice Keele's view.Perhaps most importantly, it provides my staff with more opportunities for partnerships with a broader group of institutions, as we are not bound to collaborate with universities within our group.For me, universities have the majority of their issues in common. We must be prepared to come together strongly around these issues, rather than simply allowing the compartmentalisation of the sector to provide an easy option for policymakers and resource providers to engage with the mission groups which, by definition, only ever represent a minority of the sector.Professor Nick Foskett is vice-chancellor at Keele University – follow it on Twitter @KeeleUniversityThis content is brought to you by Guardian Professional. To get more articles like this direct to your inbox, become a member of the Higher Education Network.ResearchPartnershipsKeele UniversityHigher educationguardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds     Frederic Franklin, an exuberant, British-born ballet dancer who was an early inspiration for choreographers George Balanchine and Agnes de Mille and a frequent stage partner of the renowned ballerina Alexandra Danilova, died Saturday at a New York hospital. He was 98. Read full article >>     Loop readers know the heart-warmingly redemptive tale of Michael D. Brown , the former Bush loyalist tossed out of his FEMA job after Hurricane Katrina, only to emerge as a vocal administration critic and speech-giving

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