Univariate Regression, expectation of x given y
What is the difference between linear regression on y with x and x with y?
I have a dual boot laptop (Windows 10). I ran general updates and now my Ubuntu won't boot.   I ran in recovery mode and still it freezes in the same place.      Kernel panic – not syncing: Attempted to kill init! exit code=0x00007f00 Legend in tikzpicture The height of a string in a gravitational field in 2-dimensions is bounded by $h(x_0)=h(x_l)=0$ (nails in the wall)  and also $\int_0^l ds= l$. ($h(0)=h(l)=0$, if you take $h$ as a function of arc length) .  What shape does it take?  My try so far: minimise potential energy of the whole string,  $$J(x,h, \dot{h})=\int_0^l gh(x) \rho \frac{ds}{l}=\frac{g \rho }{l}\int_0^l h(x) \sqrt{1+\dot{h}^2} dx$$  With the constraint  $$\int_0^l \sqrt{1+\dot{h}^2} dx- l=0$$ If it helps, it's evident that $\dot{h}(\frac{l}{2})=0$.  Generally, this kind of equation is a case of a constrained variational problem, meaning that the integrand in  $$\int_0^l \frac{g \rho }{l}h(x) \sqrt{1+\dot{h}^2} +\lambda(\int_0^l \sqrt{1+\dot{h}^2} dx- l)dx$$  Must satisfy the Euler Lagrange equation. The constraint must also be satisfied.  But, in truth, by this point I am clueless. $\lambda$ is worked through $\nabla J  = \lambda \nabla(\int_0^l \sqrt{1+\dot{h}^2} dx- l)$. I have tried this , but get nonsensical answers.  Is this method the best? If so, in what ways am I going about it wrongly thusfar? Why does Linux show both more and less memory than I physically have installed? Singular or plural "set"? I'm having some issues with a sentence that is part of the purpose in a report that I'm writing. I'm not sure if the word "communicate" (in bold) should be singular or plural.  The applications in the "set" will communicate with each other, not with other "sets".     The purpose of this report is to develop a sample set of applications   that communicates between services on the internet, mobile devices   and a central processing unit in a motor vehicle. How to avoid NoMethodError for nil elements when accessing nested hashes? Encopresis, I'm at my wits end? Does anybody have suggestions? I normally dual-boot with 12.04 and Win XP pro sp3 on a Thinkpad R60.  I needed to reinstall windows because of problems piling up, so I ran the computer's built-in hard-disk recovery software.  I told it not to mess with the other partitions, but somehow it deleted the Linux partition.  That's what I was using to backup all of my windows files, so now everything I have is gone.  I just ran the USB setup with linux, and the partition is deleted - it just shows it as empty space.    Is there ANY way to get all of my files back? Alignment issue in 'Your Sites' section in the Android app Prevent Mac Terminal from reverting to default theme I can't find any way to change the Terminal theme and have that theme applied permanently.  I want to change to another darker theme other than the default 'basic' theme, and (most importantly) have it remain as the theme every time I open Terminal. Is there a word for someone who somewhat delights in their illnesses/medications? I don't understand, because if 'don't' is 'do not' then wouldn't the sentence without conjunctions be 'do not you dare' which I'm pretty sure isn't grammatically correct. Like, when we say the term it means something else, certainly not 'do not you dare' anyway. Any ideas on why? I am so glad English is my first language. Grep: unexpected results when searching for words in heading from man page I'm running into weird behavior when trying to grep a man page on macOS. For example, the Bash man page clearly has an occurrence of the string NAME:  $ man bash | head -5 | tail -1 NAME   And if I grep for name I do get results, but if I grep for NAME I don't:  $ man bash | grep 'NAME' $ man bash | grep NAME   I've tried other uppercase words that I know are in there, and searching for SHELL yields nothing whereas searching for BASH yields results.  What's going on here?  Update: Thanks for all the answers! I thought it worth adding the context in which I ran into this. I wanted to write a bash function to wrap man and in cases where I've tried to look up the man page for a shell builtin, jump to the relevant section of the Bash man page. There might be a better way, but here's what I've got currently:  man () {   case "$(type -t "$1")" in     builtin)       local pattern="^ *$1"        if bashdoc_match "$pattern \+[-[]"; then         command man bash | less --pattern="$pattern +[-[]"       elif bashdoc_match "$pattern\b"; then         command man bash | less --pattern="$pattern[[:&gt;:]]"       else         command man bash       fi       ;;     keyword)       command man bash | less --hilite-search --pattern='^SHELL GRAMMAR$'       ;;     *)       command man "$@"       ;;   esac }  bashdoc_match() {   command man bash | col -b | grep -l "$1" &gt; /dev/null } Javascript to check whether a checkbox is being checked or unchecked I'm basically searching for the opposite of putting all your eggs in one basket, where the risk is total failure because you did not hedge your efforts. I'm searching for a phrase that encompasses splitting your efforts and evokes the prospect of failing at both. A bird in the hand is worth two in the bush also encompasses a sense of having focused your efforts, but only alludes to total failure. To satisfy the criteria, the phrase must cover:  attempting two things (or multiple iterations of one thing) both of which you might succeed at, if you addressed them serially but both of which you fail at because you address them in parallel  Here are the idioms/phrases that do not sufficiently cover the idea and why:  &quot;A servant to two masters&quot;  This has the sense of competing priorities, but not the sense of failing to achieve your goals.  &quot;Jack of all trades. Master of none.&quot;  The sense is insufficiently pejorative. Being a jack-of-all-trades can be seen as an advantage; I'm trying to focus on the lack of mastery.  &quot;The man who fancied himself a wit, and was half-right.&quot;  From Christopher Hitchens. Hilarious, but lacking the sense of split effort between two things.  &quot;Walking and chewing gum at the same time.&quot;  An idiom for multi-tasking, not for failing to multi-task. Edit Addressing a few suggestions and another one that occurred to me:  &quot;Hedging your bets&quot; or &quot;Betting against yourself&quot;  In this case, you cannot win both bets, but you will almost certainly win one. You limit your upside, but also limit your risk. I'm looking in particular for total, catastrophic failure due to split attention/effort.  &quot;Can't walk and chew gum at the same time&quot;  Failing to do two fairly simple things that most everyone can do, not failing at two hard things because you tried to do both.  &quot;Robbing Peter to pay Paul&quot;  In this case, Paul gets paid. If you were to rob Peter to pay Paul, and get robbed yourself before you could get the money to Paul, that'd be closer. :)  &quot;Spreading yourself too thin&quot;  An actual English idiom, but missing the implied sense of failure.  &quot;Too many irons in the fire&quot;  &quot;A lot of irons in the fire&quot; can be viewed positively, so this is missing the sense of a strategic misstep.  &quot;Between a rock and a hard place&quot;  The sense is of needing to act but having no good alternative.  &quot;Falling between two stools&quot;  My favorite answer so far because it does appear to be an actual English idiom (not a proverb). In that sense, it's great, but some of the usages are closer to a failure of  than a failure of effort. And falling between two stools implies that the attempted action was simply sitting down.  &quot;Chasing two rabbits and catching none.&quot;  This is the exact sense I was looking for, but it appears to be a cross-cultural proverb rather than idiomatic English like &quot;putting all your eggs in one basket&quot;. I'll be accepting it, and using it in my work! But if there are other ideas, please let me know. Google Chrome: Version 32.0.1700.107 m  This happens when displaying the profile and clicking on the number of visited days/consecutive.  . Why are the dineutron and diproton unbound? How to install an application that requires gksu package on ubuntu 18.04? I downloaded the Upwork desktop App on ubuntu 18.04. When I open it with Gdebi package installer I saw this error:    I tried to install gksu manually via sudo apt install gksu but I got this error  Building dependency tree        Reading state information... Done Package gksu is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'gksu' has no installation candidate   How can I install this software on ubuntu 18.04 (I download it yesturday so it is the most recent version on upwork website) ? How can I prevent Google mistakenly offering to translate a page? Several of my site's pages are appearing in search results with [Translate this page] next to it. When I click that it takes me to Google Translate and translates my page "from Catalan to English".  The pages are in English but have a couple of foreign words (actually Japanese romanisations, not Catalan) that appear to be tripping Google up.  A few weeks ago I set the html tag to &lt;html lang="en"&gt; which from research appears to be the best method to specify the language of a document. Google has cached the pages with this attribute but it is still offering to translate.  More research led me to a "notranslate" attribute which prevents translation entirely: &lt;html lang="en" class="notranslate"&gt;. The problem now is users cannot translate from English to their desired language!  Are there any other solutions that force Google to parse my site as English only? Unable to play MP3 or MP4 files in Rhythmbox or Movie Player I am unable to play any MP3 or MP4 files. When I try to open any MP3 or MP4 file, both show an error, a Python 2.7 plug-in is required.