If my data is stationary, can I also write that it is homoscedastic? Does stationarity imply homoscedasticity of the data?
I'm having trouble distinguishing between the concepts of scedasticity and stationarity. As I understand them, heteroscedasticity is differing variabilities in sub-populations and non-stationarity is a changing mean/variance over time.   If this is a correct (albeit simplistic) understanding, is non-stationarity simply a specific case of heteroscedasticity across time?
What are the origins of the word "nice"? How do I drag and drop files into an application? I've seen this done in Borland's  environment, but I'm not sure how to go about it for a C# application I'm working on. Are there best practices or gotchas to look out for? Intensity of light If we have 2 beams of light with equal intensities, but with different frequencies, wouldn't the one with the higher frequency generate more power?  If so, how come the intensity, which is in $W/m^2$, of the higher frequency beam is not higher? Focus existing terminal with `Ctrl-Alt-T` shortcut Output the common lines (similarities) of two text files (the opposite of diff)? Diff is a great tool to display the changes between two files. But how to display the similarities of two text files (while ignoring the differences)?  I.e. sample input:  a: Foo Bar X Hello World 42  b: Foo Baz Hello World 23   Pseudo output (something like this):  @@ 2,3 =Hello World   Just sorting both files and using comm is not enough, because in that case the line information is lost. I am new to the telecom simulations system specially multisim, which I am having a project that I want to simulate.  My project in (Analog Communications) is consisting to have FM Transmitter (Modulator) that accepts a generated signal (Sin, Cos) and get me the modulated output as a Graph.  I've found this FM transmitter circuit (3 km range):   ![two muppets][1]  and I am building that circuit on Multisim, and I failed. Because I faced many problems, first of, the variable capacitor symbol is weird here in the multisim, and the regular capacitor doesn't have variable options. Secondly, when I Use signal generator as (Sin, Cos), the output gets weird after 5 second of the simulation.  I want to show the input signal (before modulation) and the output signal (transmitted or modulated).  I guess my output result where not the as expected, as the signal (Sin with phase 90&deg;) is giving weird result of few seconds of simulating.  Below are screenshots of the simulation results within time.          Any ideas how to edit or fix the above circuit to have this output is similar to what it should be? Countinuity of the identity map between different topologies Is  (i.e. repulsive gravity) possible in string theory?  I have read some articles about scientists making assumptions about the existence of anti-gravity, but is it possible in string theory? How do you use Excel server-side? A client wants to "Web-enable" a spreadsheet calculation -- the user to specify the values of certain cells, then show them the resulting values in other cells.  (They do NOT want to show the user a "spreadsheet-like" interface. This is not a UI question.)  They have a huge spreadsheet with lots of calculations over many, many sheets.  But, in the end, only two things matter -- (1) you put numbers in a couple cells on one sheet, and (2) you get corresponding numbers off a couple cells in another sheet.  The rest of it is a black box.  I want to present a UI to the user to enter the numbers they want, then I'd like to programatically open the Excel file, set the numbers, tell it to re-calc, and read the result out.  Is this possible/advisable?  Is there a commercial component that makes this easier?  Are their pitfalls I'm not considering?  (I know I can use Office Automation to do this, but I know it's not recommended to do that server-side, since it tries to run in the context of a user, etc.)  A lot of people are saying I need to recreate the formulas in code.  However, this would be staggeringly complex. How to change the base of logarithmic-scale plots? Why is a person's location exclusively tied to their communicator? In Star Trek it is frequently seen that when a crew member wants to avoid being tracked, they'll leave their communicator somewhere (quarters, corridor etc) which throws the computer and ship's security off their trail.  However, the entire interior of the ship is under constant surveillance by the internal sensors. Barring damage to the ship or sensors, or some space phenomenon causing radiation X to create interference, why aren't these internal sensors able to continue tracking every person on board regardless of where their comm-badge is? In the worst case, they should be able deduce who the errant individual is by simple subtraction: "I can see where all the other comm-badges are, so subtract them and the remaining life form must be the person I am looking for." But this never seems to be done either.  Is Star Fleet security really so inept or is there some other limitation in play that is never mentioned? Need assistance shrinking MDF File Verbose logging was accidentally left on for one of our database ballooning our database MDF file from roughly 90GB to 192GB.  We've disabled verbose logging, truncated the logging table but now we want to shrink the MDF file to reclaim disk space as the drive the MDF file is on is only around 200GB. I don't have the luxury of increasing its size. Our disk space monitoring tool is alerting me that drive space is less than 8% over and over and over.  Given this is the first instance this has ever happened, we don't expect to ever need that extra 102GB of disk space again. We'd like to reclaim it.   I've tried to use the GUI to shrink the database and the files but it doesn't actually change in size. I've also tried using DBCC SHRINKFILE and DBCC ShrinkDatabase with NoTruncate and TruncateOnly. No matter what I do the file doesn't seem to budge.  One potential issue is that somehow the database initial size is 188GB. Deleting and re-creating the database isn't a very practical option for us so how can I shrink the MDF file and reclaim our disk space?  Running dbcc shrinkfile('My_Data'), I get the following results:  DBID: 5  Field: 1 CurrentSize:24030464 MinimumSize: 128 UsedPages: 17770472 EstimatedPages: 17770472   The database MDF file is still the same size (192,243,712 KB).  The table has a clustered index:  Name:TRACES ObjectID: 394588594 Type: Clustered Index/b-tree   The query:  SELECT     name,     size/128.0 - CAST(FILEPROPERTY(name, 'SpaceUsed') AS int)/128.0 AS AvailableSpaceInMB FROM sys.database_files   ...for the database I am trying to shrink, returns:  Name: My_Data AvailableSpaceInMB: 48693.375000 Name: My_Log  AvailableSpaceInMB: 67028.437500   I've also tried shrinking in small chunks using a PowerShell script that shrinks in 20MB increments. That also doesn't change the size of the MDF file.  I've tried dbcc shrinkfile(My_Data) without any other options from SQL Management Studio. It runs for a long time, finishes, and the MDF file is still the same size. Specifying a target size, it runs for a good 30-40 minutes (finishes) and nothing changes file size wise.  I ran this: DBCC SHRINKFILE (N'My_Data' , 139045) and get the following results:  DbId: 5 Field: 1 CurrentSize: 24030464 MinimumSize: 128 UsedPages: 17808744 EstimatedPages: 17808744 Showing range on hexagonal grid Here is the situation.  I have hexagonal board,and a unit on it,with speed or move value 4.Diffrent terrain has a diffrent cost.When i click on the unit,game should show me a move range.  My solution was to check each  hex in range of 4,with A* pathfinding,and if path cost was less than 4 then this hex was in range.Finally game nicely show me range of that unit.  My question is:   Is there other solution to search for range on hex grids or square grid,because even if i am really proud of what i did in my solution,i think,it is a little to exaggerated?:))  What make me ask this question?I noticed that when unit speed is 4 or 6 or even 8,time to computing range for my computer was really good,but when speed was 10 and more i noticed that i needed to wait few second to compute.Well in real games i rather dont see something like this and my A* pathfinding is rather well optimized,so im thinking that my solution is wrong.  Thanks for any replies. How to block sites with iptables Can I accept an already rejected edit (to my own post)? Today,  to one of . Before I got to see the notification, the edit already was rejected by other people (three rejections, one approval).  But the edit was actually a good one (like most edit proposals to my post I get to see) – a correction of syntax errors, so I would have definitively approved it.  (The suggested edit didn't change the main point of the answer, which was about the API to use, but it made the code example of my answer actually usable. I didn't compile it when writing my answer, it was late at the evening.)  So I did edit my post to include the proposed change, so the proposal is not fully lost. But the proposer only got the negative feedback from the rejection, and none of the reputation bonus an accepted edit gives.  My suggestion: Could there be added a way a post author can accept edits which were already rejected by other users?  Also, is there some way I can contact the rejectors and teach them not to reject good edits? There is a length limit to Windows file extensions? Shouldn't the twoside option produce a wider margin at the binding/spine edge, rather than the other way around? I'm using \documentclass[twoside]{report}. utf8 and ISO 8859-1 encoding references trouble I have to use one particular template ( am obliged to use it for my thesis) it uses \bibliographystyle{plain} Ihave both english and frensh text on it (for abstract and résumé) there is no problem for characters like ( é, ç...) but some of references does not appear they are replaced by [?] knowing that foe encoding \RequirePackage[latin1]{inputenc} how to fix this problem please!   \documentclass{article}   \RequirePackage[latin1]{inputenc}   \RequirePackage{fancyhdr}     blabla \cite{nayak2015comprehensive, byun2002applications, shah2004sequential, fletcher2009support, cornuejols2011apprentissage, byun2002applications}   @article{nayak2015comprehensive,    title={A comprehensive survey on support vector machine in data mining     tasks: applications \&amp; challenges},    author={Nayak, Janmenjoy and Naik, Bighnaraj and Behera, HS},    journal={International Journal of Database Theory and Application},    volume={8},    number={1},    pages={169--186},    year={2015}    }      @inproceedings{shah2004sequential,     title={Sequential k-nearest neighbor pattern recognition for usable      speech classification},     author={Shah, Jashmin K and Smolenski, Brett Y and Yantorno, Robert E      and Iyer, Ananth N},     booktitle={Signal Processing Conference, 2004 12th European},     pages={741--744},     year={2004},     organization={IEEE}     }      @misc{fletcher2009support,      title  = {Support vector machines explained},     author = {Fletcher, Tristan},     journal= {University College London, London},     year   = {2009},     howpublished = "\url{http://sutikno.blog.undip.ac.id/files/2011/11/SVM-     Explained.pdf}",     note   = {Accessed: 2017-04-30}     }      @inbook{cornuejols2011apprentissage,      title={Apprentissage artificiel: concepts et algorithmes},      author={Cornu{\'e}jols, Antoine and Miclet, Laurent},      year={2011},      pages={279--309},      publisher={Editions Eyrolles}       }      @incollection{byun2002applications,      title={Applications of support vector machines for pattern recognition:       A survey},      author={Byun, Hyeran and Lee, Seong-Whan},      booktitle={Pattern recognition with support vector machines},       pages={213--236},      year={2002},      publisher={Springer}      }    \end{document}  knowing that my references work well on other template but this one no how to fix this problm please! here is the error I got   Edited here is the link to the template  in fact I have created a littele example ( since I could not publish my thesis ...) the error has disappeared but my references still [?] Loading external GeoJSON file into Leaflet map? I would like to load a geoJSON (polygon) file into my leaflet map. I have seen examples where geoJSON is embedded into the javascript code but I can't find any examples showing how it is done with an external file.   &lt;head&gt;     &lt;meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"&gt;     &lt;link rel="stylesheet" href="http://cdn.leafletjs.com/leaflet-0.5/leaflet.css" /&gt;     &lt;script src="usStates.geojson" type="text/javascript"&gt;&lt;/script&gt;     &lt;style&gt;         html, body, #map {             height: 100%;         }         body {             padding: 0;             margin: 0;         }     &lt;/style&gt; &lt;/head&gt;  &lt;body&gt;     &lt;div id="map" style="height: 100%"&lt;/div&gt;     &lt;script src="http://d3js.org/d3.v2.min.js?2.9.3"&gt;&lt;/script&gt;     &lt;script src="http://cdn.leafletjs.com/leaflet-0.5/leaflet.js"&gt;&lt;/script&gt;      &lt;script type="text/javascript"&gt;       var map = L.map('map').setView([38.57, -94.71], 4);      L.tileLayer('http://{s}.tile.cloudmade.com/9067860284bc491e92d2342cc51d47d9/998/256/{z}/{x}/{y}.png', {attribution: 'Map data &amp;copy; &lt;a href="http://openstreetmap.org"&gt;OpenStreetMap&lt;/a&gt; Imagery © &lt;a href="http://cloudmade.com"&gt;CloudMade&lt;/a&gt;'}).addTo(map);      var featureStyle = {         "color": "#ff7800",         "weight": 5,          "opacity": 0.2     };      L.geoJson(usStates).addTo(map);      &lt;/script&gt;  &lt;/body&gt; How do I derive the Lorentz contraction from the invariant interval? Reviewing some basic special relativity, and I stumbled upon this problem:  From the definition of the proper time: $$c^2d\tau^2=c^2dt^2-dx^2$$ I was able to derive the time dilation formula by using $x=vt$: $$c^2d\tau^2=c^2dt^2-v^2dt^2=c^2dt^2\left(1-\frac{v^2}{c^2}\right)\rightarrow d\tau = dt\sqrt{1-\frac{v^2}{c^2}}=t/\gamma$$  Now, I would very much like to be able to derive the length contraction formula in a similar fashion, and feel strongly that this should be possible. The definition of the invariant interval is: $$ds^2=dx^2-c^2dt^2$$ using $t=\frac{x}{v}$ I tried: $$ds^2=dx^2-\frac{c^2}{v^2}dx^2=dx^2\left(1-\frac{c^2}{v^2}\right)\rightarrow ds=dx\sqrt{1-\frac{c^2}{v^2}}$$  This is where I'm stuck: I don't see how this can be converted to a Lorentz factor...  Any help that will allow me to arrive at the desired result $ds=\gamma dx$ would be very much appreciated.