Extension to Classical Coupon Collectors Problem
Coupon Collector Problem with Batched Selections
I installed the  on my Ubuntu&nbsp;11.04 (Natty Narwhal) with   sudo apt-get install lamp-server^   Now I navigate to /var/www and use   wget http://ftp.drupal.org/files/projects/drupal-7.x-dev.tar.gz   I get the following error.   --2011-08-03 13:59:00--   http://ftp.drupal.org/files/projects/drupal-7.x-dev.tar.gz Resolving  ftp.drupal.org... 64.50.233.100, 64.50.236.52 Connecting to  ftp.drupal.org|64.50.233.100|:80... connected. HTTP request sent,  awaiting response... 200 OK Length: 2757101 (2.6M)  [application/x-gzip] drupal-7.x-dev.tar.gz: Permission denied   Cannot write to `drupal-7.x-dev.tar.gz' (Permission denied).   How do I resolve this error?  I tried to download the same file in the downloads folder, and it went on without an issue. So it seems to be some permission error, but I'm not sure about that or how to solve it. What is the difference between kernel drivers and kernel modules? Applying Insufficient Explanation Post Notice to One-line Questions? Moderators currently have a tool to add a Post Notice that says:     insufficient explanation       We're looking for long answers that provide some explanation and   context. Don't just give a one-line answer; explain why your answer is   right, ideally with citations. Answers that don't include explanations   may be removed.   However, there seems to be no equivalent wording for one-line questions.  Could the wording be changed to something like below to cover both one line questions and one-line answers?     insufficient explanation       We're looking for longer posts that provide some explanation and context.          Don't just ask a one-line question; provide some background like a brief description of your research prior to asking   Don't just give a one-line answer; explain why your answer is   right, ideally with citations.          Questions and answers that don't include explanations may be removed.   Sometimes such questions can simply be closed for being unclear or too broad but on the two sites I moderate there is an aversion to closing questions from new users, so to give them some guidance about what is expected, without spending time writing the same comment over and over, a post notice like this would provide a good "couple of clicks" alternative. Changing content of footline in beamer For the finite-dimensional case, we have a canonical isomorphism between $\mathbf{V}$, a vector space with the usual addition and scalar multiplication, and $(\mathbf{V}^*)^*$, the "dual of the dual of $\mathbf{V}$." This canonical isomorphism means that the isomorphism is always the same, independent of additional choices.   We can define a map $I : \mathbf{V} \to (\mathbf{V}^*)^*$ by $$x \mapsto I(x) \in (\mathbf{V}^*)^* \ \text{ where } \ I(x)(f) = f(x) \ \text{for any } \  f \in \mathbf{V}^*$$  My Question: what can go wrong in the infinite-dimensional case? The notes I am studying remark that if $\mathbf{V}$ is finite-dimensional, then $I$ is an isomorphism, but in the infinite-dimensional case we can go wrong? How? I encountered such a formula for pooled variance:  $$\frac{(n-1)s_x^2+(m-1)s_y^2}{n+m-2}\left(\frac{1}{n} + \frac{1}{m}\right)$$  Here we have two samples of the following sizes $n$ and $m$. $s_x, s_y$ are the sample variances.  I understand that the first term is a weighted average, but from the second term comes? I might end up teaching philosophy in Finnish lukio/gymnasium. I will not get an opportunity to practice teaching it - I do get to practice teaching mathematics a fair deal, though. (The situation is somewhat unfortunate.) I have taken subject studies in philosophy at university. They amount to around 60 credits (ECTS).  Suppose I give the students an exam, which asks them to write an essay or two. After that my task is to grade the exams in a fair way and comment them in such a way that the students can learn from the feedback.  -  Suppose the task was to write an essay on the problem of universals - nominalism and realism, say. Let us say 6 points is the perfect score for this task.  I would expect the students to define nominalism and realism (2 points, maybe?) and explain the problem (2 points). Remaining two points for taking some stance and arguing for it - realism is more reasonable because so and so. Partial credits for demonstrating only partial understanding.  -  Am I missing some important aspects of philosophical thinking? Should I emphasize the different parts of an answer in a different way? I suspect my perspective is influenced by fairly extensive mathematics education - is there something particular I should watch out for? How do I enable or disable Apport? The system crash dialog is annoying me, how can I turn it off? I'd also like to know how to turn it back on just in case I need it to report a problem. Should import statements always be at the top of a module? Is it possible to switch from one area of graduate study to another in US universities? For example, suppose someone has enrolled in a computer science phd program. Can he switch over to math(or physics) phd program in the same school later?(or say from applied mathematics to pure mathematics?)  What are the steps for doing for doing that? Opt out of moderator election notifications Equals(=) vs. LIKE When using SQL, are there any benefits of using = in a WHERE clause instead of LIKE?  Without any special operators, LIKE and = are the same, right? Making numeric bullets indent properly in Word Unable to mount Windows (NTFS) filesystem due to hibernation Whenever I boot Ubuntu, I get a message that it cannot mount my windows partition, and I can choose to either wait, skip or manually mount.  When I try to enter my Windows partition through Nautilus I get a message saying that this partition is hibernated and that I need to enter the file system and properly close it, something I have done with no problem so I don't know why this happens.    Here's my partition table, if any more data is needed please let me know.     Device Boot      Start         End      Blocks   Id  System /dev/sda1            2048    20000767     9999360   83  Linux /dev/sda2        20002814   478001151   228999169    5  Extended /dev/sda3   *   478001152   622532607    72265728    7  HPFS/NTFS/exFAT /dev/sda4       622532608   625141759     1304576   82  Linux swap / Solaris /dev/sda5        20002816   478001151   228999168   83  Linux Web-mapping with editing capabilities? How can I measure the execution time of a terminal process? I'm trying to measure the execution time of a process that I call via the command line (i.e., I want to find out how long it takes to for the process to finish). Is there any command that I can add to the command calling the process that will achieve this? Change logo url link I'm trying to change the logo url of the site to "mywebsite.com/side2", but it is not working, can anyone tell me where is the error in the code below?  add_filter( 'login_headerurl', 'custom_loginlogo_url' ); function custom_loginlogo_url($url) {  return home_url( 'side2' ); } Asphericity of pseudo circle Let $S$ be de pseudo circle (see for instance ).  How can I compute its higher homotopy groups?  The question came up while trying construct a weak homotopy equivalence $X\to Y$ that does not admit an inverse. Taking $X=S^1$, $Y=S$ and $f$ as in the wikipedia page should work, but I was not able to work out a "simple" way of calculating $\pi_n(S)$ for $n&gt;1$. By "simple" I mean that it should not invoke a generalization of that I am trying to prove. Use dynamic variable names in JavaScript Can I install Android on my non-Android device? Many people want to try/use Android without buying a new Android phone.  How can I install Android on my current phone or device running Nokia Symbian, Maemo, or MeeGo; Microsoft Windows Mobile or Windows Phone 7/8/10; Apple iOS (iPhone); RIM's BlackBerry OS; Palm's WebOS; Samsung's Bada; HP's WebOS; Mozilla's Firefox OS; or other phone / operating system?