Quadrant is a no-nonsense Risk Analysis Package for doing Monte Carlo Analysis in Microsoft Excel.
It is easy to use, hides nothing from the user and is ideal for both the simplest analysis and for use with large, complex models where it is essential that everything is transparent and can be checked.
All calculations are visible on the spreadsheet, so no more confusing answers seemingly plucked out of the air or formulae that don't add up when the spreadsheet is used normally - unlike some of the other "Expert" Risk Analysis packages!
This is the Quadrant website at its new home domain (www.qdrnt.com).
All traffic to the old shared domain (http://home.btconnect.com/Farnham) will be redirected.
If you link to the old site address, please modify your links to point directly to www.qdrnt.com/home.htm.
What is Quadrant, and what does it do?
What makes Quadrant different from @Risk, Crystal Ball, Predict! (trademarks acknowledged) and all the other (not inexpensive) risk analysis packages?
What form does Quadrant come in?
How do I install it?
How do I get rid of Quadrant?
What does Quadrant do to change the look of my Excel system?
How do I start Quadrant?
How do I get Quadrant to do what I want?
So how do I run Quadrant?
So what do all the other bits on the Quadrant dialog do?
I still don't understand Quadrant - what do I do?
Why develop Quadrant?
Quadrant is an add-in for Microsoft Excel. It was originally written for Excel 97, but works in more recent versions too.
Quadrant allows Monte Carlo risk analysis to be performed using Excel by providing an iteration engine that collects results from user-selected cells over a user-specified number of recalculations of a workbook.
(In English, please!)
Quadrant basically recalculates a workbook lots of times, recording the values in selected cells for each recalculation, and then automatically draws graphs and presents basic statistics about the recorded values. This is (basically) what the repetitive calculation behind Monte Carlo analysis is all about - work out what happens in each of a large representative set of possible outcomes and analyse the overall pattern of results to better understand the range and relative probability of different outcomes.
The best thing to do if you don't understand any of that is to read a bit about basic statistics and probability theory. Quadrant cannot teach anyone how to either use a spreadsheet or understand risk analysis - but if you understand at least the basics of both, you should have no problems using Quadrant.
Quadrant is a basic tool, an iteration engine, that allows you to use Excel to do risk analysis. Quadrant works the way it does so that it does not get in your way when you use Excel. It does very little that is not completely visible to the user. Whilst the aim has been to make it as simple and transparent as possible, Quadrant cannot help you perform risk analysis if you don't understand what risk analysis is. Quadrant is ***not*** a turnkey solution for risk analysis. There is no such animal. There is no substitute for understanding what you are doing.
Any analysis product that promises to "do it all for you", or that has advertising or documentation that says you don't need to understand how it works (because you can rely on the experts who designed it) is, in my opinion, at the very least foolhardy and at worst dangerous - and probably both. If you don't understand it, don't use it. Find someone (or a good book) that does understand it. If they can't explain it in your terms, find someone else (or another book). If you still can't find anyone who can explain to you what the package is doing in terms you understand then just don't use it - you are flying blind and whoever produced the package certainly didn't understand your needs so they probably don't understand your problem.
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I make absolutely no warranties or guarantees as to the accuracy, correctness, validity or usefulness of any results produced by Quadrant or any other effects on your installation of Excel or any other part of your computer system, network or electronic documents.
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Quadrant can work with any Excel spreadsheet, does not interfere with normal spreadsheet operations and stores all its data within the normal spreadsheet file. There are no special data files nor restrictions on the normal use of Excel. All Excel functions and capabilities are still accessible, and the only time Quadrant takes full control is during the iteration calculation. Or to put it bluntly - Quadrant does not mess up Excel, do anything "differently" or hide anything from the user.
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Quadrant comes in the form of an Excel add-in file that will work with Excel 97 called "quadrant.xla" (or something similar, depending on the version). Quadrant also works with Excel 2000 and later versions.
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The best way to load Quadrant and make it available any time you need it is to load it using "Tools - Add-ins - Browse" etc. to locate and load the .xla file as an add-in. Alternatively it can be placed in the "xlstart" subdirectory (folder) of the main Excel installation (location varies with version of Excel) to make it load automatically every time you start Excel. Quadrant is small and so should not use enough resources for most users to worry about, so these are good options if you don't want to mess about manually loading it each time. Alternatively, the quadrant .xla file can be located anywhere on your system and loaded manually simply by opening the "quadrant.xla" file in Excel.
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To get rid of it, the easiest way is to move or delete it from the xlstart directory, or from wherever you decided to put it. The next time Excel tries to load it, it will fail and give you the option not to look for it again next time.
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Quadrant installs a "huge" toolbar consisting of two whole buttons when it loads.
The left-hand button (a light blue Quadrant with bell-curve) starts the main Quadrant dialog and the right button (red'n'black diagonally) toggles (alternates) the colour of the selected output cells between "Auto" and "Red" (and back again) as a quick way to check which cells' values will be collected.
Quadrant also adds a "Quadrant" menu item to the "Tools" menu.
Both these alterations are undone whenever Quadrant is removed from the system.
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Well, the simple answer is to either click the left Quadrant toolbar button , or to select "Quadrant" from the "Tools" menu - this opens the Quadrant dialog. There is only one of these. Quadrant is very simple (at the moment) and so only needs one dialog box to set up the main runtime settings and provide a "Go do it!" button.
But the simple answer doesn't get you very far .......because first you need to put stuff in your spreadsheet to tell Quadrant what to do when you run it.
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Quadrant is "data driven". To use Quadrant, you have to put "instructions" **in the spreadsheet** to tell it what to do.
This is ***not*** as difficult as it sounds.
Quadrant uses information in "comments" (Excel 97) - for Excel 5 & 95 they were referred to as "cell notes" - to identify which cells it needs to worry about, based on settings specified in the main dialog box.
Ok, best way forward is with an example..
Say we want to grab the results for cell B34 (and a bunch of others at the same time).
So we decide on a "Tag" or short group of characters to use to identify each of these cells. Let's use "XQP9a" (OK, use anything else you like instead - I used gibberish here to show that you can use any combination of letters and numbers).
So we select each of the cells we want in turn and put "XQP9a" at the beginning of the comment - press Shift-F2 to edit comments for the selected cell. It is a good idea to add some more details to each selected comment to identify the cell uniquely later - so the comment for B34 might become "XQP9aCell B34 Sample A Results". Quadrant can use the extra information to help you identify the results later.
That's as far as we need to go to get the thing set up for use. Remember- we used "XQP9a" to "tag" the cells we were interested.
More info about using Cell Comments and Tags
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Once cells have been tagged, you can start up the Quadrant dialog box - like you may have done before you realised you needed to put special stuff in the spreadsheet to get any sense out of it.
So you're now looking at the Quadrant dialog box and wondering what all these settings could possibly do?
The first one is easy - the Source Cells "Tag" box is where you put "XQP9a" (or whatever else you decided to use - the default, as you can see is "output"). When it runs, Quadrant just looks for cells whose cell comments begin with whatever you've put in this box. These cells can be anywhere in your worksheet. To see which cells Quadrant has identified, you can press the "Toggle" button on the Quadrant dialog, or the right-hand button on the Quadrant toolbar.
A useful characteristic of this is you can select groups of cells to process hierarchically.
Whaat ! ?
Say you set the comments for four cells to "Output1Cell1", "Output2Cell2", "Output1Cell3" and "OutputCell4". If you then set the tag in the Quadrant Dialog box to "Output1" you would select the first and third cells. If you set the tag to "Output2" you would select the second cell only and if you set the tag to "Output" (or just "Out") you would select all the cells.
At this point it is a good idea to try a few combinations of "tags" in comments and "tags" in the dialog box to get the feel for how it works.
No need to actually run Quadrant, just try changing the tag value in the Quadrant dialog box and take note of which cells change when you press the "toggle" button.
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Iterations - specifies how many times to recalculate the spreadsheet and capture the results.
The maximum for the trial version is 250 times. This should be enough for users to get a good feel for the system and to use Quadrant to solve simple problems.
I know that this is not a large enough number for serious statistical or multi-variable risk analysis work. What I am hoping is that I will get enough feedback from people who want to use Quadrant seriously to both improve it to the point that it is good enough to release without the "beta" label and to decide whether it is worth releasing as a commercial product. The real limitation for the current way Quadrant does things is iterations must be less than the maximum number of rows that Excel supports in a spreadsheet (65536). If people seriously want more than this, then that can also be done, though with some minor changes to Quadrant's data handling.
Active Sheet Only - tick this box to limit recalculation to the active sheet only at each iteration. This saves time for large workbooks with formulae on other sheets but where the values in the selected output cells do not depend on values in worksheets other than the active sheet.
Tag - the string of characters to look for at the beginning of comments to select cells for output.
Toggle - flips the colour of selected cells between "Auto" (usually black) and red, to see which cells are selected. (Does the same as the right hand button on the Quadrant toolbar)
Graph Bins - the number of subdivisions to display for output histograms.
Exact Bins - sets the size of subdivisions to the range of output values divided by the number of graph bins.
Integer Bins - sets the size of subdivisions to the nearest integer (particularly useful for graphing results that consist of integer values only).
Neat Bins - sets the size of subdivisions to values rounded to about two significant figures.
Output Graph Examples
Again, the best way to appreciate the differences in the different bin size options is to try each of them out and see which one works best to illustrate the key aspects of your results. Also take a look at the examples pages for illustrative examples.
Report Sheet Suffix - this is an optional "extra bit" that will be added the end of each report sheet and can be used to identify a given iteration run. Setting this to "1" then "2" for different iteration runs would not only allow two separate sets of data to be collected but also avoid the "Sheet xyz already exists. Do you want to overwrite it?" query. It's a way of being able to retain previous results, without being forced to rename worksheets manually to prevent them being overwritten.
[Working Data Sheet]
Name - unsurprisingly, the name of the sheet where all the values from each of the selected cells will be placed during the iteration run. Change the name of this sheet here to allow you to keep the values recorded during previous runs.
Keep Working Data - specifies whether to retain or delete the working data sheet after the run is complete.
Go away, Cancel, Close, Get me back to Excel, Bored with this game etc.
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Well the best thing to do (even if you do think you understand Quadrant) is to experiment; play with Quadrant, try out different scenarios and settings to see how it reacts. Have a look at the example spreadsheets posted elsewhere on the site. Run them, modify them and run them with different settings enabled and try to figure out why the results change as they do, and how you might make use of it.
If you think you understand how it works, then try to fool it, break it and generally push the envelope. If you understand its limitations, then you will be able to use it more confidently - and if you find a real flaw then I'd like to hear about it! Also, if you have a really good example spreadsheet, or way of using Quadrant that you would like to share with others, e-mail me a copy and I will post the best of them on the site.
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The Quadrant software, documentation (including information on the Quadrant web site) and all accompanying materials or information is provided as-is with no warranty express or implied. No claim is made regarding its operation or suitability for any particular purpose and no liability will be accepted for any consequences of the use or storage on any system of any of the software, documentation, accompanying materials or information. No licence is granted to use or hold any copy of the software or accompanying materials except under these terms.
As an individual user or corporation you may under non-exclusive licence use the limited beta version of Quadrant for a single consecutive period 90 days.
As an individual user in full time education you may under non-exclusive licence use the limited beta version of Quadrant for an unlimited period whilst you continue in full time education as a student or are employed as an academic staff member at an institution recognised by your government as a school, university or college.
You may copy the version of software described in this document, together with this document in its entirety, for backup or to pass to another party so long as they agree to remain bound by any and all limitations of this and any other licence which may be granted or determined at any time by the author of the software.
No rights or ownership in or of the software or any part of any accompanying documentation or any other data files or information supplied with it are granted or transfered by this licence.
(OK - so you get to use it for free for at least a while.)
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Download Quadrant Trial version
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Please e-mail me feedback specifying the exact releases of Quadrant and Excel you are using.
Whilst I cannot guarantee an immediate or individual response, I will do my best to answer specific concerns and to fix any bugs or "unwelcome features" that are brought to my attention.
Please e-mail any messages only once.
All users sending useful (as determined by me) feedback will be added to an e-mail list which I will use to send out a general (FAQ) response to queries.
Please tell me if you would like to be included.
Users sending me particularly valuable feedback, such as the first or most informative report of a critical bug or useful suggestions for improvements may also be granted a free personal licence to use the latest version of the unrestricted release of the software, if and when it is released. Any suggestions for improvements must be on the basis that they then become my sole property, because otherwise I could not incorporate any changes without compromising further development of the software.
All e-mail feedback to : email@example.com
Kevin Farnham BSc MBA
Software and Web Pages Copyright © 1997-2010 Kevin Farnham
All Rights Reserved.