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Comment: Re:Or you know.. (Score 5, Insightful) 182

by hde226868 (#45407273) Attached to: Weak Statistical Standards Implicated In Scientific Irreproducibility
The problem with frequentist statistics as used in the article is that its "recipe" character often results in people using statistics that do not understand its limitations (a good example is assuming a normal distribution when there is none). The bayesian approach does not suffer from this problem, also because it forces you to think a little bit more about the problem you are trying to solve compared to the frequentist approach. But that's also the problem with the cited article. Just remaining in the framework and going towards more discriminating thresholds is not really a solution of the problem that people do not understand their data analysis (a p-value based on the wrong distribution remains meaningless, even if you change your threshold...). Because it is more logical in its setup, the danger of making such mistakes is smaller in bayesian statistics. The telescoper over at http://telescoper.wordpress.com/2013/11/12/the-curse-of-p-values/ has a good discussion of these issues.

+ - Iain Banks dies of cancer

Submitted by Anonymous Coward
An anonymous reader writes "BBC News is reporting that Iain Banks, best known for his Culture series novels and The Wasp Factory, has died of cancer aged 59. It had been announced several months ago that he was suffering from bladder cancer, and he had stated his intentions to spend his remaining time visiting places which meant a lot to him after marrying his partner."

Comment: Re:Current naming system is going to fail anyways (Score 2) 142

by hde226868 (#43434897) Attached to: IAU: No, You Can't Name That Exoplanet
the current naming system for stars is a.ready unique. The case that you are mentioning (alpha Lyrae etc.) is the so-called Bayer designation, that is a historic naming scheme for the around 1500 brightest stars. Official star names are NOT the Bayer names, but usually done according to their catalogue numbers. For example, my slashdot name, HDE 226868, is the donor star of the black hole Cygnus X-1, which happens to be number 226868 in the Henry Draper Extension catalogue. These names are unique. The IAU has since then gone to naming schemes that essentially are what you want already, i.e., for new astronomical objects the "names" really are the position of the object in the sky. So, for example, Swift J 164449.3+573451, a black hole candidate. This object was discovered by the Swift satellite and is at the location RA: 16h 44m 49.3s, declination 57d34m51s. (the J means that the coordinate is for the epoch and equinox 2000.0, i.e., it takes the precession of the Earth's axis into account) If the distance of this object were known, its position relative to us would be known. In a few years, when the Gaia mission is done, we will have such coordinates for all objects in the milky way. Note that your designation using "medium shifts" (similar to names used in some SciFi books and movies) is far less accurate than what astronomers can already do for those stars where distances are known, namely give spatial coordinates (x,y,z coordinates relative to Earth; you can calculate these easily based on the right ascension, declination, and distance). After the Gaia satellite, the Galactic coordinate system will be well enough known such that we can give absolute positions in a Galactic coordinate system instead of Earth centric. As the IAU notes, there is a clear precedent on how planets are named (essentially alphabetically in order of their discovery). What companies that try to "sell" naming rights are trying to do is to sham people into believing that this system does not exist. That some of that money is being used to fund science does not matter - fact is, not even the discoverers have final naming rights. And, yes, I am an astronomer.

Comment: Siding Spring Observatory (Score 2) 79

by hde226868 (#42577255) Attached to: Bushfire Threatens Major Telescope
This is a place to bring my favorite joke by Virginia Trimble: "It is Siding Spring Observatory, not Siding Springs, this being Australia, after all". I hope that the damage is small. This is the most beautiful observatory site I have been observing at. and it would be a shame to see the telescopes damaged. Not only the AAT, but also the smaller telescopes on that site have been very productive.

Comment: Re:What's the point? (Score 2) 909

by hde226868 (#42444979) Attached to: USMA: Going the Extra Kilometer For Metrication
I don't think your argument that the American system is more convenient to live in holds. If you talk to people who grew up outside of the US (like me, for example) you will find that they can think as easily in Centigrades and cm as an USAian can think in inches and Fahrenheit. For example, you wouldn't talk about a 2/3m door, but a 70cm door, and people tend to think of room temperature as 20C or 22C. I travel back and forth between Europe and the US quite often and I do not find any practical difference between both systems. I think you're spot on with your argument why metric hasn't taken over yet. It's one of the idiosyncracies of the US system that are very difficult to understand for people from the outside (others are, e.g., the electoral system, discussions on gun control, etc.)...

Comment: Re:RTFA (Score 1) 473

I have yet to see an air based heating system in Europe. In Germany, virtually all heating systems are water based. The renewable energy used to make power in Germany is not only solar but also wind based. Plus there are backup sources (e.g., water based power plants). And, adding to that an infrastructure that actually works. I live in Germany, my significant other in the US. In the past seven years I had a few seconds of power outage TOTAL. My significant other had more than one week this year alone.

Comment: Re:Misleading summary (Score 1) 459

by hde226868 (#41732075) Attached to: Scientists Who Failed to Warn of Quake Found Guilty of Manslaughter
But the point is, the occurrence of an earthquake was very improbable. This fact is not changed even by the occurrence of an earthquake shortly after.

What the scientists were asked to do is effectively the same as predicting who would win the lottery. This is just not possible - even if somebody still wins it every few weeks...

Comment: Re:Moral of the Story (Score 2) 459

by hde226868 (#41731967) Attached to: Scientists Who Failed to Warn of Quake Found Guilty of Manslaughter
I work with people from INAF (the national astronomy institute), ASI (the space agency), INFN (the nuclear physics institute), and several universities (Milan, Catania, Roma, Palermo, and others). For none of them your statements are correct, most of them (in their 40s) have around 100-150 refereed publications.

I am not going to name names on slashdot, but I really think that discussions should be based on facts and not on unfunded allegations as the ones you are bringing up here. It is not the people that are the problem, it is the system in Italy - as also evidenced by this very, very unfortunate court decision today.

Comment: Re:Moral of the Story (Score 5, Interesting) 459

by hde226868 (#41730673) Attached to: Scientists Who Failed to Warn of Quake Found Guilty of Manslaughter
Well, I know that this is flamebait, but still...

I work quite a lot with scientists from Italy in my area (astrophysics). They are among the most dedicated scientists I know and are doing world leading science. They are also among the least well paid - which shows their dedication to science.

The former Italian government (under Berlusconi) tried for years to marginalize science and research in Italy and this is yet another blow to the scientific system in Italy. The result will be disastrous and lead to an even larger brain drain of highly qualified people from Italy than what Italy has already experienced in the past 10-20 years. Everybody can imagine what this means for the long-term future of Italy as a place of innovation and science, which has already been damaged badly.

Comment: Re:let's not waste significant digits! (Score 5, Informative) 182

by hde226868 (#41337435) Attached to: Astronomers Fix the Astronomical Unit
This is correct. originally the AU was defined as the average distance between the Earth and the Sun. The problem then was to convert this distance to meters. The way to do this conversion in the end involves the product of the mass of the Sun and the Gravitational constant G. Both quantities are not well known (e.g., G is known to 4 or 5 digits only). But their product can be determined from modeling the motions in the Solar system to much higher precision. So by that time the AU was then redefined by defining the product GM (often called k^2, where k is called the "Gaussian gravitational constant"). It is my understanding that this has now been simplified. The difference between both is only a few meters.

Comment: Re:Just wondering (Score 4, Informative) 157

by hde226868 (#41031075) Attached to: US Astronomy Facing Severe Budget Cuts and Facility Closures
No, this has nothing to do with JWST being over budget. The review concerns the astronomy funding through the National Science Foundation, whose budget is independent of NASA's funding. NASA funds all of space based astronomy (including data analysis), while NSF funds ground based astronomy. NSF mainly funds the national optical astronomy observatory on Kitt Peak in Arizona and the National Radio Astronomy Observatory in Charlottesville, VA, with facilities in West Virginia and in New Mexico (plus some other states). In addition, NSF funds data analysis/theory grants. Overall, NSF's budget is much smaller than NASA's, but then, ground based hardware is much cheaper than space based. To put things in perspective: for about 50% of all university astronomers, NSF facilities are the only way to get optical observing time (the remainder of astronomers have access via privately funded telescopes, such as the Keck). The closures of the instruments proposed in the report to NSF essentially mean the US giving up its current leadership in large areas of radio astronomy, and significantly reducing access to medium sized facilities for optical astronomers, if the (realistic) flat budget for the astronomy program is realized.

Comment: Re:What the hell are they playing at? (Score 4, Informative) 176

by hde226868 (#39696189) Attached to: NASA Looking For Ideas To Explore Mars
I would assume that it is something similar to what NASA did with the ESA L-class missions last year, where they also pulled out and then held scientific workshops. NASA's problem is that it has no money to participate in ExoMars or the L-class missions, and that's why they pulled out of ExoMars. However, legally speaking NASA is required to follow the decadal reports, and the planetary one recommend Mars research. This then led to the schizophrenic situation that they have held workshops for ideas on how to do gravitational wave research (LISA), X-ray astronomy (IXO), and now apparently Mars, where they previously pulled out of all joint ventures with ESA and JAXA. However, the good thing is that with the recommendation from the decadal reports and the results from such workshops the scientists at NASA headquarters have an argument that spending some money for R&D in these areas is necessary, because they can prove need. As a result this important research does not die. There is money for general R&D in the budget, so while some larger programs have been explicitly canceled by either OMB or congress, the Mars/X-ray/gravitational wave research can at least be partially funded this way.

I'd not blame NASA for this but rather congress, which tends to try to exert strong control over NASA, which in many areas really amounts to micro-managing projects, without Congress really understanding what it is doing...

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