When using principal components as predictors in linear regression, PC1 comes out not significant
How can top principal components retain the predictive power on a dependent variable (or even lead to better predictions)?
What is inertia of a body? I'm new to Blender and am having a few hitches.  Each time I use box select on a group of vertices it extends the selection from what was previously selected.  I can avoid this by hitting A to deselect all before using Box Select but I was hoping there was a way to have this happen by default.  Isn't it the desired workflow to select groups of objects and move them independently and only extend the select with Shift?  I must be doing it wrong. When I have Excel running and I double click an Excel file in Windows explorer, I'd like it to launch in a new window by default so that I can move documents to separate monitors. Is there any way to get this behavior? Let's say that you want to output or concat strings. Which of the following styles do you prefer?   var p = new { FirstName = "Bill", LastName = "Gates" }; Console.WriteLine("{0} {1}", p.FirstName, p.LastName); Console.WriteLine(p.FirstName + " " + p.LastName);   Do you rather use format or do you simply concat strings? What is your favorite? Is one of these hurting your eyes?  Do you have any rational arguments to use one and not the other?  I'd go for the second one. I am taking my first dive into testing a mobile app.  It will be available to iOS and Android.  I've been searching for a way to test and automate iOS without having an actual iPhone or any other Mac device.  We run Windows here at the office.  I was looking to use iPhone emulators but it doesn't seem possible.  I saw Appium Studio/SeeTest but it seems even that requires iTunes and a real device.  I know you can set up a Mac vm on a Windows machine but are there any other ways to test iPhone without having to do this? In a batch file I need to extract a month, day, year from the date command.  So I used the following, which essentially parses the Date command to extract its sub strings into a variable:  set Day=%Date:~3,2% set Mth=%Date:~0,2% set Yr=%Date:~6,4%   This is all great, but if I deploy this batch file to a machine with a different regional/country settings, it fails because month, day and year are in different locations.   How can I extract month, day and year regardless of the date format? What's the difference between  and ,  and ? Root drive is running out of disk space. How can I free up space? I'm using Ubuntu 11.04 and I want to free up some space in my root directory, which is overloaded. I especially want to change the path used for installing applications (they are getting installed directly to the root drive).  Another consideration is that I'm working on a MySQL database server. The server is installed in the root directory itself, so I don't want to  risk losing any data.  Please give me some tips to help sort out this problem. How can I make a message appears on my PC when my phone is ringing? When I'm at work, I usually have a headset on my head and I am listening to music. My phone is always on vibrate to respect co-workers.  However, I don't keep the phone in my pocket because of its size, so I don't feel it vibrating.  I miss a lot of calls.  I was wondering if it's possible to forward "phone is ringing" notifications to the PC, ideally via a Bluetooth connection.  I would not mind installing a 3rd-party app on the phone or software on the PC. Irrationality of sum of two logarithms: $\log_2 5 +\log_3 5$ I try to prove that the number $$\log_2 5 +\log_3 5$$ is irrational. But I have no idea how to do it. Any hints are welcome. Can a multi-core processor run multiple processes at the same time? I understand that a multi-core processor can run multiple threads of the same process at the same time using its different cores. Can it also run multiple processes at the same time(each core running a different process)? SED: insert text after the last line? This  inserts a tag to the beginning of a file:  sed -i "1s/^/&lt;?php /" file   How can I insert something to the end of each file with sed? How fast does electricity flow? Is it safe to eat potatoes that have sprouted? I'm talking about potatoes that have gone somewhat soft and put out shoots about 10cm long.   Other online discussions suggest it's reasonably safe and the majority of us have been peeling and eating soft sprouty spuds for years. Is this correct? rake db:migrate doesn't seem to work in production How can I query the name of the current SQL Server database instance? It is a bit of a "chicken or egg" kind of query, but can someone dreamup a query that can return the name of the current database instance in which the query executes? Believe me when I say I understand the paradox: why do you need to know the name of the database instance if you're already connected to execute the query? Auditing in a multi-database environment.  I've looked at all the @@ globals in Books Online. "SELECT @@servername" comes close, but I want the name of the database instance rather than the server. I have really no idea about this:  Problem: Show that there exists a function $f:[0,1]\rightarrow\mathbb{R}$ such that:  $f$ is discontinuous in all $x\in \mathbb Q$. $f$ is increasing in $[0,1]$. $f$ is integrable.   EDIT: Sorry, it is not discontinuous in all $x\in \mathbb R \setminus \mathbb Q$, just in $\mathbb Q$. Types of things vs. types of thing How to disable copy in shared folder I am trying to make folder that everyone can view and can't copy,modify.    For all answers.I thinking about specially ms office files. I tried following methods  Software  - copy protect    - anti copy    This method can't protect save as and upload  MS office macro    Users can enable,disable macros.  MS office restriction    This is best choice but can't protect from file uploading.   Almost I found the solution. Way is combination of MS office restriction and restrict access from browsers using firewall or antivirus. But I don't exact how to do this. How did Harry, Ron and Hermione buy presents for each other? I have been re-reading the Harry Potter books again and I noticed that Harry, Ron and Hermione have been giving each other Christmas presents each year at Hogwarts. How have they been able to buy each other presents if they are not allowed to go out of Hogwarts?   From their third year on they could visit the village and buy presents there, but what about the first two years? Did they give their personal belongings? Or did they just happen to have boxes of chocolates or books to give each other?