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    I ANOVA and Linear Regression Resource

    Hello, Can someone please let me know of a resource (book or other) that explains how to use ANOVA in linear regression? I didn't even know what ANOVA was until some days ago so I'm looking for something that explains it thoroughly with deductions. The resources I've read focused solely on...
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    I Constructing an Index

    Hello, I'm facing a problem in a project that I'm not being able to solve. I have two different timeseries, and I want to construct an index that represents the two of them, each of variable weights (so I could choose 50% weight for each, or other combination). These are financial time...
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    Carcinogenic pet food

    After reading on the World Health Organization's warning that processed meat is carcinogenic (in humans), even in small daily doses, I went on to investigate if this finding also applies to pets, and found this study: "Twenty-five commercial pet foods were analyzed for mutagenicactivity using...
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    Prob/Stats Book on Neural Networks?

    Hello, Can you recommend me a book on neural networks, for a beginner in this area? I would like a book that explains the mathematics behind NN's, while still going into computational matters in a package like Matlab. My background is Physics/Maths in Bsc level. Thanks.
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    News #OcupaBrasilia - Brazil's Protests

    Is anyone following Brazil's current political situation? Brazil's unrest is worse than ever, with ongoing protests on more than 15 cities against the current government of 'Workers Party'. The economic crisis in Brazil, caused by the lowered commodity prices, namely crude oil, and the various...
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    Computer going into hibernate mode by itself

    Hello, There's a mystery in my laptop, that makes it hibernate after it's been on for awhile. I've turned off auto-hibernate/suspension in the power settings already, so this is really puzzling to me why this is happening. I want to leave the computer on during the night to do some long...
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    What software for optimization surface of 4 parameters?

    Hello, I have data for optimization that contains different values of 4 different parameters, and the respective function value based on them. I want to find the maximum of this function, while making sure it's a "stable" maximum, i.e., for nearby parameters, the value of the function shouldn't...
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    This algorithm can judge “creativity” in art like an expert

    http://qz.com/425662/picasso-genius-this-algorithm-can-judge-creativity-in-art-as-well-as-the-experts/
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    Should injuries be treated with anti-inflammatory drugs?

    Should an injury from overuse, such as a tendonitis, be treated with anti-inflammatory drugs, such as Ibuprofen, or do they retard the healing process and would it be better to just let the injury heal naturally? I found some papers supporting they harm the recovering process of the injury...
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    Another interesting thread closed

    https://www.physicsforums.com/threads/what-is-money.815161/ Why was this thread closed? https://www.physicsforums.com/threads/how-does-the-us-replace-its-exported-currency.725888/ And this one? I know it's old but it's another example of a thread being closed for superficial reasons.
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    A report on a sick man of Europe, Portugal

    I'm from Portugal, and I'm going to present our situation in the last years by not only my perspective, but from a perspective shared by many other Portuguese people, with backing off of data whenever possible. As you may know, in 2011, after 6 years of having a socialist government, we were on...
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    Which Godel statements are seen to be true by humans?

    My questions arose when reading an article about artificial intelligence, and the argument of Penrose that says that humans can see the truthfulness of statements that machines cannot. But it doesn't say what those "Godel sentences" are...
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    Need a Functional Analysis book

    I need a measure/integration theory book that covers the basics. I had already calculus, complex analysis, ODEs and topics of PDEs/Sturm-Liouville problem. More specifically I need to learn functional analysis to be prepared for stochastic calculus. Any suggestions? Thank you.
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    Prove the 3 definitions of entropy are equivalent (stat. mechanics)

    Homework Statement S(E,V) = kln(\Gamma(E) )\\ S(E,V) = kln(\omega(E) )\\ S(E,V) = kln(\Sigma(E) )\\ S entropy, k Boltzmann's constant. Prove these 3 are equivalent up to an additive constant. Homework Equations \Gamma(E) = \int_{E<H<E+\Delta}^{'}dpdq\\...
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    Bibliography to understand Fermi, Bose and Boltzmann statistics?

    I'm studying by Statistical Mechanics (Huang, page 180) but can't understand many things there, can anyone provide a good bibliography to study this? I don't understand what's an occupation number of a given momentum: if it's the number of particles with that given momentum, why can it only be 0...
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    Question about wavefunctions and their Hilbert space

    Maybe someone here can explain me something I never understood in QM: The wave function lives in the Hilbert space spanned by the measurement operator. Is there any mathematical relation of those spaces with each other?
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    Book for reference on PDEs

    Hi, I need a book that I can use for reference to solve any Partial Differential Equation imaginable, if it has a solution of course. Can you suggest me any?
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    Books with examples and resolutions of Statistical Physics problems?

    Hi, I'm completely lost in this discipline. Does anyone know of a good book with solved exercises and some examples, particularly on the 3 types of ensembles (microcanonical, canonical and large canonical), quantum mechanics statistical physics, and fermions/bosons gases? Thank you.
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    Is country-scale corruption possible without a big government?

    A big government (characterized by a significant spending as % of GDP, like the European governments, US, Canada, Japan, etc...) obviously makes it easier for a wide-scale corruption to exist. In Portugal, Italy, Greece, among others, this is where the corruption is coming from. Corruption shows...
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    An objective book about macroeconomics?

    I want to find a book about economics (especially that focus on economic growth) that is objective as possible. I don't want to read a book based in an ideology like libertarianism or socialism, because it'd be biased and filled with half-truths. I realize this may not be easy in economics, but...
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    What are the most promising research studies on cancer's cure?

    Every now and then, a news appears saying a new research could revert cancer on mice or something similar. But then I don't hear about them anymore. So what are the most promising research studies on curing cancer, and were there any promising researches before that failed when tested on humans?
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    News Riots put Sweden's open-door immigration policy in spotlight

    http://www.reuters.com/article/2013/05/27/us-sweden-riots-idUSBRE94Q0E620130527 I think the immigration debate should extend to every European country, since they're all taking non-European immigrants like Sweden is.
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    Genetic variations within and between populations

    This paper asserts these two different conclusions: How don't they contradict each other? What exactly is "variation between populations" and "variation within populations"?
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    I don't understand Q-Q plot

    I've read the article in wikipedia but I can't understand it. Can someone point me to a good explanation of what a Q-Q plot shows and how to make one, or explain to me please?
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    Is it necessary to study Euclidean Geometry before Differential Geom.?

    Hi, I'm a Physics undergraduate, and this semester I have the option to choose between Geometry (Axiomatic Euclidean Geometry) and other disciplines. In the next year I want to be ready to study Differential Geometry, but I don't know if I need to study Euclidean Geometry first. The teacher of...
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    Why not formulate QM in terms of |ψ| squared?

    I'm beginning to study QM, and as I understand all the information we can get out of system with 1 particle is the probability distribution function (which has position and time as variables). By knowing the wave function it's possible to know the probability distribution function, but that's an...
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    Does stock market create wealth?

    Is stock market a positive-sum game? As an example, let's say that in an IPO, an investor X buys all the shares, let's say 10, for $10 each (in the primary market). He spent $100, and those $100 went to the company. Next, there appears a bid of 10 shares (now at the secondary market) at $11...
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    Question about the fundamental equation of thermodynamics

    In a PVT system, knowing the function U(S,V) (or S(U,V) ) allows us to know all the information about the system, so it's called the fundamental equation of thermodynamics (and it makes sense to me because it's derived from the 1st and 2nd law). But if we know the function P(V,T) for example we...
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    Harmonic plane wave

    Hi, why does the harmonic plane wave have the form below: V(r,t)= acos[\omega (t-\frac{r\cdot s}{v})+\delta ] (r is the position vector, s is the vector that points to the direction the wave is propagating, v is the wave propagation velocity and delta is the phase constant).
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