Meaning of "optional" for 1-st argument of .call method
What is the difference between call and apply?
Central limit theorem and the law of large numbers I have a very beginner's question regarding the Central Limit Theorem (CLT):  I am aware that the CLT states that a mean of i.i.d. random variables is approximately normal distributed (for $n \to \infty$, where $n$ is the index of the summands) or the standardized random variable would have a standard normal distribution.  Now the Law of Large Number states roughly speaking that the mean of i.i.d random variables converges (in probability or almost surely) to their expected value.  What I don't understand is: If, as the CLT states, the mean is approximately normally distributed, how then can it also converge to the expected value at the same time?   Convergence would imply for me that with time the probability that the mean takes a value which is not the expected value is almost zero, hence the distribution would not really be a normal but almost zero everywhere except at the expected value.  Any explanation is welcome. Is transferring to another university an option for an unhappy PhD student? 'Good' review audits can be misleading Bluetooth indicator disappears on turning off bluetooth Everytime I turn off my bluetooth, the indicator icon in the system tray disappears, as opposed to just greying out as expected. Next time I need to go to the settings select bluetooth to turn it on, which makes the indicator to reappear.  Is there anyway I can make the indicator icon not disappear but stay greyed out when not in use? What is the difference between the | and || or operators? I have always used || (two pipes) in OR expressions, both in C# and PHP. Occasionally I see a single pipe used: |. What is the difference between those two usages? Are there any caveats when using one over the other or are they interchangeable? Notification for reviews shows way too many How can I manually create a pixel perfect image sprite? How to hide Authoring information,Revision information,Publishing options tabs in create/edit node for any content type I am trying to hide Authoring information, Revision information, Publishing options tabs in create/edit node for any content type. I tried different modules with no luck. Please give me suggestions how to achieve this. Thanks a lot "Since", "until", "from", "to" on invoices or date ranges of a form Which is the correct form on an invoice, or a general date range in a form, and why?  Monkey dolls                        12 GBP From 2012-01-03 to 2013-01-02  Monkey dolls                        12 GBP Since 2012-01-03 until 2013-01-02   Form format (dates can be modified with a datepicker):  Since: 2012-01-03 until: 2013-01-02   Since+until makes sense and sounds ok to me, yet I know I can be very wrong, at least when it comes to the common usage in the UK and/or US, since English is not my first language.  I am interested in both British and American English.  Until now I've been using since+until, yet some articles explicitly say they may not ever be used together, while some people and some other articles get deep into grammar rules which I can't really apply on the context of invoices and forms.  Here's a recent article saying since and until can never be used together (last paragraph):   Edit: The date range can start in the past or in the future, and can end in the past or in the future. However, at the time of issuing an invoice or rendering a form, you cannot know when the document will be read or how the form will be filled. My site has 30,000 visits with 86,000 page views. If the bounce rate of 54%, then does it means only 15,000 users generated the 86,000 page views or 30,000 visits generated the 86,000 page views.  My website is www.cricandcric.com  Even though I have got 86,000 page views, my site's Alexa ranking is still getting worse day by day. How do I control that? How to remove "phone style" Gnome swipe to unlock Proving : $ \bigl(1+\frac{1}{n+1}\bigr)^{n+1} \gt (1+\frac{1}{n})^{n} $ How could we prove that this inequality holds      $$ \left(1+\frac{1}{n+1}\right)^{n+1} \gt \left(1+\frac{1}{n} \right)^{n} $$   where $n \in \mathbb{N}$, I think we could use the AM-GM inequality for this but not getting how? Is there a way to recover deleted data from a SSD / USB Flash drive?  All I could find were recovery for damaged drives, but I want to recover deleted data.  So how do I do this? Add a rule after chapter title using titlesec After I installed Ubuntu 13.04, I can't mount my NTFS partition.  Error mounting /dev/sda5 at /media/mrxfly/xFLyDiskData: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,dmask=0077,fmask=0177" "/dev/sda5" "/media/mrxfly/xFLyDiskData"' exited with non-zero exit status 14: The disk contains an unclean file system (0, 0). Metadata kept in Windows cache, refused to mount. Failed to mount '/dev/sda5': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option. Using InDesign CS6, how can I simultaneously edit A4 and A5 versions of a poster? I'm on Adobe Creative Cloud, so I have the latest InDesign, and I'm attempting to design a poster for my choir's next concert. Traditionally, I've done this in Photoshop, in two separate files, however I've recently started using InDesign after converting to it to create wedding albums through Blurb.  I've created an A4 document, and created an alternate-layout for it in A5. I've then lined them up side-by-side, and I've added a black frame to the A4 page, to act as the black background for my page (by the way, feel free to advise on better ways to do this).  My assumption is that I've failed to understand how this works, as I was hoping that I'd magically get a black frame on the A5 version, and that I could use liquid layout to get this to automatically scale (along with all other elements), in order to create the two versions simultaneously.  All help/advice would be greatly appreciated! Show that $E(X)=\int_{0}^{\infty}P(X\ge x)\,dx$ for non-negative random variable $X$ top command in cygwin? I am starting to use Cygwin(64) on my Windows 8 laptop, however, the top command is not recognized. I have read online that I need to get the procps package, but it is not available on the 'Cygwin Setup' package selections. How should I go about installing the procps package so that I can use top?  ps. for whatever reason ps and kill both work so I would think top would be included in whatever package allowed those guys to work, but there is no top command. How can brackets be escaped in using string.Format? For example: String val = &quot;1,2,3&quot; String.Format(&quot; foo {{0}}&quot;, val);  This example doesn't throw an exception, but it outputs the string foo {0}. Is there a way to escape the brackets? But when I try to run it using  tar zxvf jre-8u151-linux-i586   I get tar (child): jre-8u151-linux-i586: Cannot open: No such file or directory tar (child): Error is not recoverable: exiting now tar: Child returned status 2  What is wrong? The name and place matches prefectly.