Show that $(X_1 \mid X_1 + X_2 + \dots + X_k)$ has binomial distribution, where $X_i$ has Poisson distribution $\lambda_i$
Proof that Conditional of Poisson distribution is Binomial
Terminal not displaying colors for directory listings "Interested with the course" or "interested in the course"? Interested in/with the course   Which preposition is correct? in or with, or both. Why do we need a diagonal matrix? Apart from simplifying matrix powers, why do want to diagonalize a matrix? Do they have any appealing application which can be used to motivate to study diagonal matrices.  Thanks for any answers. Two sidebars in Beamer for two presentations in one tex file Java Round up Any Number Being able to join chat rooms from the Android app would be a plus! It would truly make us connected on the go, instead of having to sit down at our desks and open a browser window. This will allow more users to fully utilize the chat system and join events no matter where they are. Can I answer my own questions, even if I knew the answer before asking? I might want to answer my own question because:  I arrived at a solution before there were any other correct answers or I like mine better, can I still answer my own question?  I have a folder with lists of code snippets for things I always forget or get wrong, such as regular expressions for processing XML, common WinForms control idioms, etc. Is it considered poor etiquette for Stack Overflow to ask a question I already know the answer to, and then self answer, just so it gets recorded on the website?   Related:          For more information, see &quot;&quot; in the . Tikz shortandoff-on newcommand problem Usually I have no problem with babel and !:, and I don't use shortandoff-on switch. But since I made a command using !#1 parameter, the problem comes up again.  The same synthax used outside the command work fine, but in the command I get the error message :  ! Package tikz Error: + or - expected.  How to solve the problem without using the shortandoff-on switch ?  \documentclass[french,a4paper]{article} \RequirePackage{etex} \RequirePackage[utf8]{inputenc} \RequirePackage[T1]{fontenc} \RequirePackage{fourier}  \RequirePackage{tikz} \usetikzlibrary{calc,intersections}  %%%%%%%%%%%%%%%%%%%%%% %%%% Francisation %%%% %%%%%%%%%%%%%%%%%%%%%%  \RequirePackage{babel}  %%%%%%%%%%%%%%%%%%% ---------------------------------------- %%%% Géométrie %%%% %%%%%%%%%%%%%%%%%%%-----------------------------------------      % #1 option du path     % #2 premier point     % #3 second point     % #4 longueur dans un sens     % #5 longueur dans l'autre     % défini Mil#1#2 \newcommand{\Med}[5][]{%     \path[#1,name path=Med#2#3] ($(#2)!.5!(#3)$) node (Mil#2#3) {}      ($(Mil#2#3)!#4!90:(#3)$) -- ($(Mil#2#3)!#5!270:(#3)$) ; }  \tikzset{small dot/.style={fill=black,circle,scale=0.3}}  \begin{document}  %\shorthandoff{:!} \begin{tikzpicture}  \coordinate[label=below left:$A$] (A) at (0,0) ; \coordinate[label=below right:$B$] (B) at (4,0) ;  \draw (A)--(B) ;  %\Med[draw]{A}{B}{1}{1} ;  \draw($(A)!.5!(B)$) node (MilAB) {}      ($(MilAB)!1!90:(B)$) -- ($(MilAB)!1!270:(B)$) ;   \end{tikzpicture} %\shorthandon{:!}  \end{document} We have a directory and want to protect that from remove and rename, but we need to be able to rename, remove and create contents. What we can do? Alternative definitions of wifebeater I was a li'l nonplussed to find out that the word  can mean other things besides "a man who beats up his wife". Its definition reads:        One who (usually as a repeated practice) beats one’s wife, or a husband prone to violence   A kind of sleeveless shirt, often but not exclusively worn as an undershirt.   (uncountable, UK, slang) Stella Artois, a brand of lager beer.       reckons that sense 2 is American and originates "apparently from the association of such a garment with men who commit domestic violence". It does not register the UK slang. I'm guessing that Stellas also have an unfortunate association with domestic violence.  Are these alternative senses popular in their respective countries or are they perhaps nonce words that have lingered on? Any idea how these disparaging associations came about? I expect that the brewers of Stella Artois are none too happy about it. How exactly using VB6 can I can call any Windows shell command as you would from the command-line?  For example, something as trivial as:  echo foo I read this book once when I was in middle school. A girl solves a murder or a mystery on a spaceship. It was a thin paperback books.   All I can remember is that there was an alien, and there was a movie star or actress or famous makeup artist on the ship traveling with another woman. By the end of the book the murderer was the woman the actress was traveling with who forced her to use her makeup skills to disguise her, and she was really some kind of alien. sf:INVALID_OPERATION: INVALID_OPERATION: testLevel of NoTestRun cannot be used in production organizations While deploying code in vsCode from sandbox to production I get the below error      sf:INVALID_OPERATION: INVALID_OPERATION: testLevel of NoTestRun cannot   be used in production organizations   As per the error, I need to change the value of testLevel but I am not able to find where and how can I change it to RunLocalTests  Could someone please help me to change the value of testLevel in vsCode Conjugate Variables, Noether's Theorem and QM In which way does quantum mechanics disprove determinism? I've heard this pop up in a discussion with my physicist/engineer roommates, but didn't care to ask at the time.  Now I'm mighty curious about it.   doesn't really seem to say much on this issue.  From what I understand about the Uncertainty Principle, it says that there are certain properties of electrons and stuff that cannot be measured, and are therefore uncertain.  Then Wikipedia (under ) states that Sir Arthur Eddington says that the Uncertainty Principle isn't really so because we can't measure these properties, but because turns out nature is indeterministic.  At least that's what I took from those paragraphs.  Even without my biased wording, it sounds more like an assertion than evidence.  I've also read a few things about how other scientific conventions perceive the issue, like how a ball on the peak of a perfect mound might randomly roll down in any direction, and I'm still unconvinced.  My belief of determinism is generally that if you knew every single variable that existed as a factor at the very beginning and birth of the universe, you could correctly determine all properties of any individual particle at any point in time.  Could anyone provide some more background about this?  Especially regarding quantum mechanics? So, I'm running linux Mint (but I guess the same applies to Ubuntu) and as is common knowledge, their TeX distribution tends to be slightly outdated. Now I can't have none of that and decide to install it with the install-tl from the TeXlive homepage. Somehow, I cannot install it as a normal user (this I find normal as it is installing in the root directory), so I proceed to install TeXlive   sudo perl ./install-tl   and add the paths to .bashrc. All is well and my TeXlive installation works. Except for the texhash option. Running it as a normal user is no problem, except that I installed TeXlive as root, and so running texhash as normal user doesn't do anything (directory not writable. Skipping...). No problem I think, I'll just do it as root. But somehow texhash isn't installed for root.  Now, texhash is somehow connected to updating the directory tree, but I don't really know what it does. I use it on my ~/texmf/ folder to add my packages to a global path (I think), but when looking at info for this question I see in a comment for  question that this is apparently not needed, though I don't understand what I'm to do now.  So if I'm not adding new packages from CTAN or updating, I really don't need texhash and all is good?   To summarize: I'd like to know:    Why should I need texhash? Can I avoid installing as root on linux Mint/ubuntu ( they say you don't have to be root, that it's even discouraged)? Should I somehow install texhash for root?   I realize this might be a vague question at best, but I didn't find an answer I readily understood, so I'd appreciate any thought on this. find . -name *.rb   doesn't work on my ubuntu  I have to do  find . -name "*.rb"   to get it to work.  Why is that? The new profile shouldn't mistakenly imply that you can earn the Informed badge on a meta site I just joined Sports, and I decided to take a look on Sports Meta. I clicked on my profile there. This is part of what I saw:     Yet the profile shouldn't indicate that it is, in theory. . .  This seems to be a bug. How can I avoid Java code in JSP files, using JSP 2? Is the product of two Gaussian random variables also a Gaussian? Say I have $X \sim \mathcal N(a, b)$ and $Y\sim \mathcal N(c, d)$.  Is $XY$ also normally distributed?  Is the answer any different if we know that $X$ and $Y$ are independent?