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  1. 0

    How to get published

    I have discovered something in mathematics (related to graph theory) that seems interesting and as far as I know (some google searches + asking around on IRC) it may be original. What steps do I take now? As an undergrad I have access to professors. So I figure I would approach a professor I...
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    News Free speech zones?

    (is there already a thread on this?) I was doing some reading about public spaces re the thread about prayer, and stumbled on this: http://en.wikipedia.org/wiki/Free_speech_zones#_note-sfgate which linked to this...
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    Bayes net inference

    I don't understand this simple algorithm from Russel & Norvig for computing a distribution of X given certain observed values e: function Enumeration-Ask(X, e, bn) returns a distribution over X inputs: X, the query variable e, observed values for variables E bn, a Bayes net with...
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    Who said it?

    I have found a quote I've been looking for. It's the lower one in my signature right now: "Science is everything we understand well enough to explain to a computer. Art is everything else." However I don't know just who said it. Most web sources say David Knuth, but some say Donald Knuth...
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    Graph algorithm

    I'm just posting a random graph algorithm problem for discussion fodder, since another interesting graph algorithm post was removed due to a threatening-sounding title and lead-up. This is from Cormen, Leiserson, Rivest, & Stein, 22.4-3 (not a homework problem of any kind, just for fun--I had...
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    Mac 10.4.8 /usr/bin

    Through an incrediby boneheaded mistake, I have deleted my /usr/bin directory on my MacBook. Fortunately it only had a small number of programs that weren't there by default. Also, most of the GUI seems to run just fine without the bin directory, and the computer boots. But I do not know how...
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    New Laptop

    I need to get a laptop in addition to my desktop computer for doing presentations/demos and general academic use--carrying it around all day every day in a backpack while cycling/walking a few miles. I'm still undecided. I am torn between a model from Sony's TX series--unfortunately I do not...
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    Over-searching error (statistics)

    I guess this should properly go in the Programming forum, but I think I might get a better response here. My question is with respect to statistics (context of machine learning) about "over-searching" error. You have a search space S of all possible models, from which you choose a subset K...
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    Verifying directory structure

    Are there standard tools for verifying that a directory structure takes a certain form? This is for when a program needs certain minimum files with certain name constraints to be in certain places and directories with certain name constraints to be in certain places. It would specify things...
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    Object paradigm: message passing

    I've been thinking about the object paradigm, more specifically the claim that method calling represents "message passing" between the objects. At least in Java, (and also, according to Wikipedia, in Smalltalk) this doesn't seem strictly true to me; it seems more like function calling than...
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    Markov blanket

    Is there a simple (meaning, memorable and not just a lot of crunching through probability formulas) proof that a variable is independent of the other variables in the network, given its Markov blanket?
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    I hate error handling

    Error handling obfuscates code. For someone reading your code, what your program does when there is an error is usually unimportant--at first they care only what it does when it works properly, and maybe later they'll come back to the errors, but understanding your error handling is a very low...
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    Tri-Achnid, an Adobe flash physics-based game

    Tri-Achnid, an Adobe flash physics-based game http://www.google.com/search?hl=en&q=tri-achnid&btnG=Google+Search I just think that this is the best piece of media I have seen in a very long time. It is hard to maneuver your tri-achnid at first but it is cocaine once you get the hang of it...
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    Asterisk in pathname

    I have a bunch of links that are like http://us.rd.yahoo.com/dailynews/rss/topstories/*http://news.yahoo.com/s/ap/20061105/ap_on_re_mi_ea/iraq (that's one link) with an asterisk and then a new address in the middle of them. Is that for a special-purpose Yahoo script or is there a...
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    Combinatorial proof-is this rigorous?

    First, please don't give me too much information or suggest other ways to do it if you think this is not rigorous. This is not supposed to be collaborative. I am asked to prove that n!^{n+1} divides (n^2)!. I thought of a few ways to try to do this, but the first thing I got is the...
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    Data hiding considered harmful?

    I've been thinking about functional programming and what really makes it different from imperative programming. It's not that you can prove things more easily about programs written in it--that may be true, but most programmers do not prove the correctness of most of the code they write so it...
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    Algebra problem

    This assignment has not yet been turned in, so I do not want any unfair help on this whatsoever. Please just give me a "yes" or a "no." Do not explain. The question: Let G be a group acting on itself by conjugation. Show that if a and b are conjugates in G, then the centralizers C(a) and...
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    How do you learn algebra?

    I am taking modern algebra and I'm not having an easy time. The problem, I think, is the symbolic manipulations. I like discrete/graph theory/algorithms/computing type math because the arguments tend to be high level, conceptual, and mostly in English. However, when a proof depends on a bunch...
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    5-ary trees

    This was a question on the combinatorics midterm: if a tree contains only vertices of degree 5 and degree 1, and the tree has 4n+2 vertices, how many vertices of degree 5 are there? With k the # of vertices of degree 5 and j the # of vertices of degree 1, the accepted answer used the...
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    String difference

    I have a need to compute a "difference" between two strings A and B. The idea is that B is similar to A, except it has had operations of string deletion and string insertion performed on it. An operation of deletion transforms a string xyz into a string xz (x, y, z being strings) and an...
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    Auto-update signature

    I just learned Python a little while ago and I'd like to write a script that will change my signature periodically (from a preset list). I don't have much experience with this type of programming. Anyway, I ran Ethereal and captured the packet that changes my sig, and then I tried to resend...
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    Attaching hard drive?

    I need to attach an ATA/IDE hard drive to a Linux computer and I'm pretty clueless about how to go about it. I have installed Linux on my desktop computer's SATA hard drive (pretty much the only computer available to me that I can open up and poke around in) and I also have a linux livecd...
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    Java How do you use Java's Hashtable?

    I need a hashtable, but I can't seem to figure out how Java's Hashtable or HashMap classes are supposed to work. The keys in these classes are objects, not numbers. How does that even work? The only thing I can think is that the addresses of the keys (which are objects) are mapped to integer...
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    Schools How are withdrawals looked at for graduate school/employment?

    How are withdrawals looked at for graduate school/employment? They do not affect GPA at all but is there a downside besides not having finished the course?
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    Pigeonhole principle homework

    I'm having trouble with some homework problems related to the pigeonhole principle. This HW is solitary work, but some more examples might help--here are some unassigned problems I haven't been able to do: Show that any subset of n+1 distinct integers between 2 and 2n (n >= 2) always...
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    Diff Eq boring?

    Is introductory differential equations boring? I can take another course and DiffEq is what I am considering mainly because it is mentioned a lot. I have no real need to take this course, unless it is useful in AI. If I take the course it will be taught at a general level in a class of 60...
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    Combinatorics or information theory?

    I have to choose between two classes because of a schedule conflict: CS 575, combinatorics and graph theory This course is taught by the chief undergraduate advisor and earlier I mentioned to him that I'd be taking the course. So politically it may be a good idea. The course says it...
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    AI in mind or brain sciences

    AI in "mind or brain sciences" Why is AI part of the description of the mind or brain sciences forum? Most work in AI has nothing directly to do with the human mind or brain. It's a division of computer science.
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    Geometry statement

    I have devised the following statement and a short proof of it: No polygon may be tiled by convex quadrilaterals, each of which shares exactly one face with the polygon. Is this known or trivial, or where could I find out if it is?
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    Superclass or Member Variable

    There is essentially no difference between a superclass of a class and a public member variable of that class. For example, if you define public class Blob { public int mass; } then defining public class Ball extends Blob { public int radius; } provides all the same...
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