Tuesday, 2 June 2015

We need to talk about Excel

I'm not sure when it happened. I've got a feeling that the writing's been on the wall since the introduction of the 'Ribbon' menu.

I was the guy who could make Excel dance... Shortcuts flying, interactive dashboards, external data connections and VBA. I loved Excel.

A colleague, observing me building a spreadsheet a few years ago, said, "F*ck me, it's like watching Minority Report".

Proud moment.

Not any more.

Modern Excel is a mess.

It's worth taking a moment to consider how we got here. Excel was first released as Windows software with version 2.0 in 1987. It's nearly thirty years old.

Back when I started out as an analyst in 2000 - who was genuinely excited that a company had seen fit to employ him and to allocate him a desk and a PC - we were using Excel 97. This was the first version to contain proper VBA and also came with Clippy, the universally reviled Office assistant.

Clippy aside, Excel 97 was pretty good. It had most of the useful functions and features that you'd find in modern Excel and it worked.

Crucially, Excel was what you got. It was restricted to 65k rows and its charts looked bloody awful, but there wasn't really an alternative.

Having VBA baked-in made Excel tremendously flexible (and the bane of IT departments everywhere). With a bit of creativity, you could use it for statistical modelling, interactive dashboards, as a calendar, a project planner, a to-do list... And we did. Excel got (ab)used as a solution to every business problem going.

Back in 2000, Excel was the centre of an analyst's world. What happened?

Specialist software has chipped away at Excel's 'jack of all trades' USP.

If a computer can do it, you can probably make Excel do it. That's no exaggeration. VBA is behind Excel and so if some functionality doesn't exist out of the box, then you can add it. You want games in Excel? Here are fifty. Be warned: I make no guarantee those games won't royally screw up your PC. VBA can do that too.

When you break down the uses for Excel, you find new competitors are encroaching on all sides. Competitors that are designed to do a specialist job, to do it really well and that integrate with each other to provide a complete solution. For statistical modelling, you've got R, SciPy, Matlab... For visualisation, you've got R (again), Tableau, Qlik View... For data storage you've got a vast array of options and for data processing (ETL), you've got Alteryx, Pentaho and again, the list goes on.

That's just the things that Excel is actually for. Under the list of things that Excel has been abused to make it do, there are hundreds of better options. Many of them free. If you want a to-do list, for goodness sake pick something that's designed to do that job.

Excel is like a Leatherman multi-tool. You can get most DIY jobs done with it if you try hard enough.

But a Leatherman is rarely the best way to do any specific job. You want a proper screwdriver, or a full-size hacksaw, or to have a corkscrew for your dinner party that's not also attached to a pair of pliers.

A specialist's toolkit looks like this. One tool - the right tool - for each job.

This is Excel's problem in 2015. It's trying to do everything - often by bolting on more plugin tools - and so it's doing almost everything badly.

Excel's a great way to make some very average looking data visualisations, or to store your data in a way that makes it really difficult to manipulate quickly and to refresh. Excel can deliver a crap interactive dashboard to a (SharePoint) web page and it can do statistical modelling that's really hard to repeat, and leaves no audit trail.

Yes, you can sort of fix those issues, with plugins and macros and hacking and creative thinking, but that's back to fixing your motorbike with a Leatherman, when you could have had the full range of Snap-On tools.

Modern Excel has one more problem. And it's a biggie...

You can't be a beginner's introduction and a specialist's cutting-edge tool at the same time

Yes, I'm going to start with a rant about the Ribbon menu. It was a stupid idea when it was introduced and it's still a stupid idea now. When you watch an experienced user manipulate a familiar piece of software, you'll rarely see them touch the mouse, because it's a slow way to do what you want.

Microsoft introduced the ribbon to make features more prominent for selection with the mouse (and presumably with a view to the arrival of touch-screens). With subsequent releases, more and more features have moved into areas where they are difficult or impossible to access with the keyboard; try formatting a chart, or even saving a file in Excel 2013.

This might sound like a petty complaint, but it's a symptom of a very serious issue. The Ribbon and mouse / touch control were a big two-fingers to experienced Excel users.

Excel has been progressively dumbed-down to make it easier to access for inexperienced users.

Which is absolutely fine.

Except that simultaneously, Microsoft has introduced PowerBI, with features that aim squarely at advanced data manipulation and visualisation. I've tried them and to be frank, they're not up to scratch. They're awkward to install, difficult to use and when you do get them to work, they produce very average looking output.

Excel has ended up in a place where it's too advanced and has too many features for novice users and it's not as good as a dedicated toolkit for specialists. That's not a comfortable place to be.

Where now?

Excel has a strong defensive position, in that big IT departments like it because it's part of a suite of Microsoft software that they're already buying. As a business analyst, you also need Excel plus other tools - if only because everyone else still uses it - so it's not going anywhere in a hurry.

That defensive position is being eroded on all sides though. Particularly because you can get a lot of the competitors that I've been discussing for free. If your corporate IT environment isn't completely locked down, then you can make a lot of headway with open source, start to get your best work out into the world and then argue about commercial software licences later...

There is also one thing that Excel is truly brilliant at and it's not to be dismissed lightly. Sometimes you want a multi-tool. Just for a quick job, because it's easier than delving into the big toolbox. Excel is a fabulous tool for this. For quickly reformatting one-off data, for banging out a functional chart, or for correlating a couple of variables, you can't beat Excel.

Microsoft should recognise this use for Excel and take it right back to basics. Turn it into a Leatherman; a lightweight, portable, do-anything, data scratch-pad, that's not trying to be more.

They'll still need a full featured BI solution of course, and possibly something else that targets less experienced users, but stop trying to make Excel the scaffold that holds the whole data analysis structure together. It's not working and if my experience is anything to go by, it's leading experienced users to actively dislike the product.

If Microsoft don't produce that lightweight scratch-pad for data, I firmly believe that somebody else will and that could spell the end of Excel as a tool for serious analysts. Excel will have been replaced for the one task at which it is still the best option.

Monday, 23 March 2015

In praise of modesty

One of these people invented the World Wide Web.

The other talks about it.

One of these people is the best footballer in the world.

He's not the one in the gold shoes.

More of this please.

Monday, 16 March 2015

The Hitchhiker's Guide to the Solar System | Tableau Iron Viz Entry

So this year, I couldn't resist. Tableau set the challenge to build something - anything - with Wikipedia data and they've put prizes on the line. It's enough to tweak the competitive streak in any analyst...

But what to build? I started out with Football League data as it's familiar and I do a fair bit with those numbers already, but then @ChrisLuv did something really nice along the same lines and I got a bit bored scraping even more football results. It felt like time for a short break from football analysis and it would be nice to learn something new during the build.

I'm not sure where the Solar System idea that I've gone with came from - possibly a friend complaining recently on Facebook that his daughter keeps attacking his ship in Elite: Dangerous - but a quick browse on Wikipedia turned up nice, consistent datasets for planets and moons and some really lovely imagery. Definitely dashboardable.

I've been trying recently to reduce the numbers of screens in my Tableau work, because experience is showing that users can sometimes be reluctant to move around a multi-screen dashboard. If the landing page does a good job, you've got a good chance of converting new users to your interface, but if it requires more clicks to get to data, then things become much less smooth.

So, the task I set myself was a one page dashboard to explore the Solar System, and with enough interesting features to be worthwhile entering into the Iron Viz contest (I hope! That's not an intimidating task, honest).

Building on games like Elite, I also wanted it to look and feel something like the in-flight navigation computer in a space exploration game.

There's a bit of how-to guidance in the rest of this post, but first, here's the Hitchhiker's Guide to the Solar System...

 Hitchhiker's Guide to the Solar System

Navigation's a straightforward task of clicking the planet you want to see at the bottom of the screen and then you can also browse that planet's moons on the right-hand side.

If you really want to pull apart its inner workings, then download the workbook from Tableau Public and have a play. Here's a quick top-line guide to get things started.

Look and feel

Most of setting up the look and feel of the dashboard involved turning off features in Tableau. No axis lines, no grid lines, no titles for the dashboard elements, no tooltips and no row banding in tables. Everything was switched off via the Format menu and the background set to black everywhere.

If you set up one sheet the way you want it, then you can copy that sheet to make more without doing all of the formatting again. (P.S. Please can we have templates, Tableau? Pretty please?)

A green web-safe "Lucida Console" font on top of the black background gives a nice flight-computer feel.

Select a Planet

This is pretty easy once you know how Tableau custom shapes work.

I downloaded a high quality image (more on image quality later) of each planet from Wikipedia, saved them to my local Tableau shapes folder and then mapped them to the planet names.

The selector is a regular chart, with the axis set to logged distances from the Sun, planet images as shapes and planet sizes defined by their radius. Dashboard actions using that chart as a source, control the rest of the vis.

And a couple of extra tricks to tidy things up...

  • The planet labels are on the second axis, so that they all display at the same height rather than each one hugging close to its own icon
  • You can't use planet radius data exactly as it is to set the sizes of shapes, because Saturn has rings and so the planet itself ends up being too small. I created an extra field to boost Saturn's size up to where it should be.

Large image of selected planet

This is done the same way as mapping shapes onto the 'Select a Planet' chart, right? Unfortunately not. You can do it that way, but it looks a bit rubbish, because Tableau compresses shapes to speed things up. If you blow them up too large, they look like this.

It's not totally unacceptable, but seems a real shame to lose those gorgeous high-resolution planet images from Wikipedia.

The trick to getting high resolution images that change on a filter, is to use Map - Background Images. You make a 1x1 scatter chart, with the planet image set to show as background, depending on what's selected on the filter. Don't forget to make the single data point on the chart transparent!

Here are the settings:

The 'target' surrounding the planet is just a floating png image with a transparent background. I drew the four corners in PowerPoint and exported them as a picture. As much as PowerPoint is the work of the Devil, it's a really quick, easy way to create simple coloured lines and add them to your dashboard!

Planet data

This one's easy. It's a straightforward table with a black background and all of the lines and other formatting turned off.

The little benchmarking chart to the right of the table is designed to provide some context. When you look at a statistic like 24.79m/s2 for Jupiter's gravity, is that a lot compared to the other planets?

The chart itself is a Gantt bar, with a dashboard action that highlights the currently selected planet and lets you quickly see how it compares to its neighbours. Using a percentage table calculation instead of absolute values lets us put all the planets on the same mini-chart and stops the ticks for huge "Mass" numbers, compressing everything else down towards zero.

Select a moon, to see data and image

We've seen these techniques before - it's exactly the same as the large planet image and planet data table. I used a simpler chart - without custom shapes - as the selector because some moons are very small and others have very similar orbits, so they can cluster closely together.

Gustav Holst. Just because we can.

This one's a bit of a cheat in that it's not data from Wikipedia, but I just couldn't resist.

Classical music and space games and movies go hand-in-hand, so I used a URL action to call Grooveshark's embedded music player with tracks from Gustav Holst's Planets Suite.

It's not really hard to do - click share on a Grooveshark track and pull the link out of the embed code that it generates. Add that link to your dataset.

Then drop an empty Web Page element onto your dashboard and create a URL action that calls the field containing the link. Tableau will automatically throw the link at the empty Web Page element when you make a selection.

Edit: I previously had some discussion here of issues with Tableau Public, when you try to embed a link to an http address. Thanks to @ChrisLuv you can safely ignore all of that and only need to know that you have to use an https web address for whatever you link to, in order for it to work properly in Tableau Public. Just switch "http" for "https" in whatever you link to and you should be fine.

There's a little warning message hidden underneath the Grooveshark player link, just in case the web browser that's viewing doesn't have flash enabled and so doesn't load the player, but most people should never see it.

I also put that warning text in a calculated field, that hides it when Earth is selected. Holst took inspiration for The Planets Suite from astrology and so there isn't a track for Earth. Wikipedia says so. See, I used Wikipedia data on Holst. It wasn't cheating after all!

And we're done. Phew. Fingers crossed, it's time to press submit on the entry...

Wednesday, 11 March 2015

My data analysis toolkit

Growing out of posts like "Losing touch... Or why Excel and VBA won't cut it any more" and "How to do football analysis in Tableau", I've been asked a steady trickle of questions this year about what analytical software I use.

One of the biggest discoveries I've made as I branched out from Excel and VBA is that there isn't a right answer to what software you should use. There are loads of programming languages, loads of dashboard solutions, loads of databases and you can't possibly get experienced with all of them.

It's better to find yourself a set of tools that work and to know those tools well, than to have bits of knowledge all over the place, but not be using any of your kit to its full potential. If your data size isn't measured in terabytes, then you don't need to be right on the bleeding edge.

For outside of work projects, I've got a couple of machines that aren't anything fancy. An older Core i5 laptop with 4GB ram and a Core i7 laptop with 16GB ram. A regular laptop like that, costing between £500 and £1000 is more than enough for chucking around datasets up to tens of millions of rows and analysing them.

On to the software... As I said, there isn't a right answer to what you should use, but I hope this post might be useful to a few people as a starting point. If you've broken Excel and if Access has you tearing your hair out then read on. Opening Microsoft Access at all, is a very strong signal that you need to get acquainted with some of the tools on this list.

And as an added bonus, almost everything I'm going to talk about is free!

Question: Can I get by without Microsoft Windows?

Answer: Yes! You need Linux Mint.

Mint is a very Windows-like desktop environment and since the Windows 8 (Metro) car crash, it's arguably more Windows-like than Windows is.

Easy to install and easy to use, I wrote a short intro to Mint, a couple of years ago.

Be warned, that if you use Linux for anything more than a bit of web browsing, you are going to end up using the command prompt and Googling to fix broken things. But then you'll be doing that with the DOS prompt in Windows too, because a lot of data analysis software is designed around Linux and needs persuading to work properly with Windows.

If you've got an older machine lying about, stick Mint on it. You might be surprised at how good it is.

Question: Which database?

Answer: MySQL Community edition

Yes, there are newer, fancier Big Data technologies out there and I'll learn them at some point, but I want the SQL language I know, in a fast, familiar, free package and MySQL does that.

On Linux, you might have to do a bit of reading to get it to work properly (watch that you need to install the Server and Client packages), but it powers half the internet - including Twitter - and isn't too hard if you're patient and don't mind Googling an error message or two.

On Windows, make sure you download the MySQL Installer. Don't try to work out what packages you want and install them individually. You will inevitably bugger it up.

Once you've installed MySQL, if you're using it for data analysis rather than to power a small website, you MUST customise my.ini (Windows) or my.cnf (Linux), or it will run like treacle. Out of the box, MySQL is designed to run on really low-powered hardware and its memory usage settings are turned way down. Have a Google.

To go with your MySQL Server, you'll want MySQL Workbench, which you can use to write queries and maintain your database. It's packaged up in the Windows Installer that I mentioned, or you can install it separately on Linux.

Don't know any SQL? You should. Start here.

Question: Which programming language?

Answer: I use Python and I like it a lot.

If you're making the switch from VBA Macros, or taking your first steps in programming, then Python's a powerful, approachable place to start.

On Windows, I'd recommend installing ActiveState's Python package, because it handles all the set up for for you and prevents you from getting into a situation where you're pretty sure you installed Python but it just doesn't work.

On Linux, you already have Python installed and you just need a nice piece of editing software to write your code in.

On Windows and Linux, for writing code I've recently adopted PyCharm following a recommendation from @penaltyblog and it's the most straightforward editor I've seen that still has all the features you'll want as you progress.

It might feel a bit weird coming from Excel Macros that the editor you use to write code and the programming language itself are separate things, but that's Open Source for you - it gives you choices. MySQL is the same; you don't have to use MySQL Workbench to talk to your database if you don't want to and there are loads of other choices, but Workbench is an option that works and that's what this list is all about.

No idea how to use Python? Start here.

Question: What do you use for statistical analysis?

Answer: I use R.

R is free and tremendously powerful. It's a proper, highly capable programming language for working with data and the output you can produce using it is amazing.

Unfortunately, it's also got a learning curve that's close to vertical. Your first steps after working through tutorial examples, will not be easy. I'm definitely not an expert, but I'm improving...

The first step with R is to install R Studio, which makes life much easier. Don't try to install and use R without R Studio - it's unnecessarily painful.

The second step is to have a look at a beginners tutorial.

And when you get stuck, have a look on Stack Overflow. R errors can be really awkward things to Google, partly because it's just a single letter and partly because its user forums are horrible. Stack Overflow and R Bloggers will already have answers to most problems you'll hit and if they don't, you've probably got the wrong end of the stick and are asking the wrong question.

Ask a question on Stack Overflow at your own risk. Chances are somebody else has asked the question before and you could have found it by searching. The bar on what is a good question asked in the right way, is also set quite high!

As an aside, if you don't know R or Python, then they are interchangeable for a lot of work, such as web scraping. R is a statistics package with a lot of general programming capability and Python is a programming language with some really good statistics packages. You could try to stick with just one of them.

Question: And for graphs and data visualisation?

Answer: Tableau Public. And R again.

For a basic grounding in Tableau, try my  "How to do football analysis in Tableau" guide. Tableau's a fabulous piece of software and a brilliant way to get interactive charts and tables onto the web. It's also my first stop for visually interrogating a new dataset and seeing what it contains.

Tableau Public - which is free - is limited vs. Professional in that you can't load more than a million rows of data at a time and you can only connect to spreadsheets, text files and Microsoft Access. It's well worth working around those limitations though, to get access to the powerful tools that Tableau offers.

When I want a visualisation that's more bespoke than Tableau offers, I turn to R packages, because that's what I know. There are a whole host of other amazing technologies out there for bespoke data visualisation, like D3 and Processing, but it's very much a case of picking your battles and learning what will be most useful to you. I'm not a graphic designer and so am sticking with R and Tableau for now.

Question: Is there still a place for Excel?

Answer: Absolutely, there is.

Excel's still a very useful tool, even if only because you know exactly how it works, so you can use it to solve problems quickly. It's also very handy that almost everybody else has got a copy so you can share spreadsheets easily.

More and more though, I'm seeing Excel as a scratchpad for hacking data around before I put it somewhere more permanent. You can see what you're doing with Excel and for small to medium sized datasets, it works really well, provided what you're building is a one-off view of data that doesn't need to be updated.

Actually, I wish Microsoft would recognise this use for Excel, strip out all the crap and cut it right down. Just a blazingly fast spreadsheet, with worksheet formulas, pivot tables and simple charting. Nothing else. It'll never happen though.

As soon as your work starts to morph into repeatable analytics, or proper dashboarding, get it out of Excel. We used to use Excel for everything because it was all we had. That's not true any more.

The free alternative to Excel is Libre Office Calc and it's just about okay. If you haven't got Excel, it's worth installing but you'll end up in MySQL, R and Tableau earlier, because Calc is a lot less capable when you throw a sizeable amount of data at it.

Question: Any other bits and pieces?

Answer: One or two...

Notepad++ is a must for text editing and definitely put the Poor Man's T-SQL formatter plugin on it, so that you can clean up your SQL queries. You don't realise Wordpad is rubbish until you try something else that works properly.

Pentaho Kettle is cool and worth a look if you want drag and drop ETL (extract, transform, load) for your data. I got very excited about Kettle a while ago and I still use it quite a bit, but you may find that R steps up to do the same jobs as you get better at it.

Gephi is what I used to draw my analyst network visualisation. It's a piece of software focussed on networks rather than general purpose analysis, but a lot of fun to play with.

And finally, Digital Ocean is an awesome web service, where you can spin up a virtual Linux PC (they call it a Droplet) for $5 a month. When I want to run a web scraping Python script without the risk that my laptop will reboot half way through, I stick it on Digital Ocean. You can also put a 20GB MySQL server in the cloud this way and access it from anywhere. It won't be super fast for the basic $5 a month, but it's very handy if you access data from a few different places. If you use this link to sign up, you'll get $10 free credit and I'll get a bonus too. Everybody wins!

I hope that this post might set one or two people off trying new tools. As I said at the beginning, this isn't claiming to be the right answer to what you should use, or even the best answer, but it's a tool kit that's working for me and took quite a bit of sifting through different options to arrive at.

If you disagree with any of the choices, do hit the comments section. I'm always looking for better options, but only if learning them will save time in the long run...

Monday, 9 February 2015

How to do football analysis in Tableau | Part 3

If you've been working through these posts, so far you've copied some football data from a website into Excel, cleaned it up and learned to build simple tables and charts with that data on a Tableau worksheet.

In Part 3, we're going to create our first interactive dashboard.  We'll make a dashboard that lets you select a team and then it will show you which are that team's strongest players.

If you had fun messing about with Tableau in Part 2 and learning by building loads of different views (I really hope you did. Screw instruction manuals. Including this one), then you might want to start a brand new Tableau workbook at this stage and connect to your Excel data again. Have a look at the early bits of Part 2 if you can't remember how that worked.

Make a new worksheet and drag Mins, PS%, Assists and Goals into the view, then split the rows by Player Name and Position. You're looking for a view like this.

PS% is a downright unhelpful name for Pass Completion %, so right click it in the Measures Area (bottom left of the screen, remember?) and rename it. Tableau will then automatically change the name wherever else you've already used it.

It might be good at this point to also change Pass Completion from Sum to Average. It doesn't really matter, because you've told Tableau to split the data by player and there's only one row of raw data for each player, so Sum and Average are the same. If you'd split by team instead though, and then summed pass completion, the data wouldn't make any sense because Tableau would add all of each team's players' pass completion rates together.

Right click the little green lozenge for Pass Completion % and change it from sum to average. If you really want to see the difference that makes, take the Player Name split out of the view for a moment and try Sum and then Average.

It always helps when you're using Tableau, to keep in mind what your underlying dataset looks like, otherwise sum and average (and as you get more advanced, weighted averages) can get you into trouble.

Back to the table... At the moment, our table has got players from both teams in it and we don't want that, because we're building a dashboard that will show us one team at a time.

Drag "Team" from the Dimensions area and drop it in "Filters".

You'll get a pop up showing you Liverpool and Everton. Tick Liverpool and click OK.

Now our table only has Liverpool players in it. Name the worksheet "Player List" (double click the worksheet's tab at the bottom of the screen) and then we're done with this one for the moment.

Add a new, blank worksheet and we'll also make a chart for our dashboard.

Let's try for a chart that will show us who's played a lot of minutes and who's playing well.

Drop "Rating" from the Measures area onto the Columns shelf and "Pass Completion %" onto the Rows shelf.

Tableau will guess that you're trying to draw a scatter chart, because you've dropped Measures where you'd normally drop Dimensions.

What we've got isn't tremendously useful though. It's a scatter, but with all of the players summed into a single point and we want them split out.

Drop "Player Name" onto Detail in the Marks area and Tableau will give you a point for each player.

Detail is essential for scatter plots and for maps. It tells Tableau at what level you want to see your data split out.

This still isn't a great chart though. Nobody has really low passing percentages or a really low rating, so let's tell Tableau that we don't need to see zero on the axes. Right click each axis, choose "Edit Axis", untick "Include Zero" in the top right corner, and press OK.

We're getting there. The chart shows who has good pass completion and who gets a good rating on WhoScored. If you hover the mouse over a point, it will tell you which player it is and whoever is up in the top right hand corner has good passing and a good WhoScored rating.

We can do better than that though. Grab "Mins" from your Measures area and drop it on Size.

Now the chart is showing who's played well (ish. This isn't very advanced analysis!) and whether they've had lots of minutes this season. Larger blobs means more minutes.

Drop "Team" from Dimensions onto Color and you'll be able to See Liverpool and Everton separated out. It would be nice if Liverpool were in red though...

Double click on a colour in the legend and you can change it.

(Worried about colour blind people? You could drop "Team" onto Shape as well. Don't leave it there though, because it will look a bit rubbish and we're only going to show one team at a time in a minute.)

Finally, drop "Player Name" onto Label and suddenly you'll be able to see who's who.

Rename your worksheet to "Player Scatter". We've got two worksheets and can build a dashboard!

The idea of dashboards is that you can drop multiple worksheets onto them and link them together. It lets you build screens that contain a mix of tables, charts and maps, where each piece of the dashboard is coming from one worksheet.

Make a new dashboard screen, by clicking the button next to your sheet tabs at the bottom of the screen.

In the new dashboard screen that pops up, you should see all of your worksheets appear in a list in the top left. Grab "Player List" (you did rename your sheets, didn't you?) and drop it onto the large white dashboard space.

The table you built earlier appears.

Now grab "Player Scatter" and do the same thing. Keep the left mouse button held down and you can see what will happen if you drop the worksheet into different places - at the top, on the left, or on the right. We want it on the right.

You should get something like this. Tableau put the chart on the screen and also the legend for your chart in separate boxes on the right hand side that you can move if you like. It looks rubbish. We can fix that.

Depending on the resolution of your monitor, Tableau has drawn you a default dashboard screen size and shape, but it's unlikely to be exactly what you want.

As a little aside, you can tell Tableau to draw a fixed dashboard size - that will never change no matter who loads it - or one that will try to adapt to different users' monitors by resizing itself. In my opinion, dashboards that resize themselves are usually crap and to be avoided. Tableau's not good enough at reshaping each element on the screen and if somebody loads your lovingly constructed views on a low res monitor, they'll look awful. You can set limits to the resizing, but it's much better to just fix the size and make users with low resolution screens scroll around a bit.

Use the dashboard size options in the bottom left to make a screen that is Exactly ('Exactly' is in the dropdown box) 1150 x 600.

That gives you a nice widescreen shape that will fit on a decent resolution laptop monitor. If you find it's half off your screen and there are scroll bars, you can make it smaller if you want.

Now that you can see both of your dashboard elements properly, it's time to make this dashboard interactive.

Remember adding the Team filter to your table so that it only showed Liverpool? We want to show that filter on this dashboard screen.

If you click in the area occupied by "Player List", you'll see a grey box appear around it. In the top-right corner of that grey boundary box, there's a tiny little down arrow, next to the x. It's really small but it is there and it's one of the things brand new users tend to miss.

Click that little down arrow, find "Quick Filters" and click "Team".

The filter that you created earlier will be pulled onto the dashboard, with only Liverpool ticked. If you hadn't already created that filter, Tableau would have just made it for you and also automatically put it on the underlying worksheet.

Tableau's default filter for a text column like Team, is a list of options with a tick box next to each, so in this case you get an option for Everton and Liverpool and (All) at the top. Sometimes this is what you want, but we'd like this dashboard to just show one team at a time, with no option to select both.

Filters have options on a little down arrow, just like the one we used on the "Player List" screen. Click in the area that your filter is occupying so that its grey boundary box is shown and use the menu to select "Single Value (Dropdown)".

That's given us a tidier dropdown box that will always take up the same amount of space on the dashboard if later on we decide to add more teams to our data.

You can also get rid of the (All) option on that box, so that people are forced to choose a team. In the same menu you just used, go to "Customize" and untick "Show All Value".

Our menu is ready!

Well, nearly. Change it from Liverpool to Everton and watch what happens. The table will switch from Liverpool to Everton, but the chart stays the same. That's no good. Currently, the filter is only linked to our table, not to our chart.

Use the menu on the filter (tiny little down arrow again) one last time to select "Apply to Worksheets" and "Selected Worksheets".

Then tick "Player Scatter" in the box that pops up and click OK.

Now try changing the filter. You've got an interactive dashboard!

When you add filters, you can choose to apply them to just one worksheet, to a selection of worksheets, or to everything that uses this data. The key thing to bear in mind is to make it obvious to users how your dashboard works. Filters that randomly change some things but not others are really, really confusing.

As far as this quick introduction goes, we're done! You've acquired data, loaded it, drawn tables and charts, built a dashboard and made it interactive and that's quite enough for today.

The only thing that remains is to share your masterpiece with the world.

In the File menu at the very top of the screen, click "Save to Web".

You'll get a popup box asking for your Tableau Public login. Remember your Tableau Public login? You made it in Part 2.

Give your workbook a name and hit Save. After a few moments, Tableau will pop up your workbook in all its glory, on the web. You can share it with anybody from here and they'll have exactly the same interactivity through filters, as you did in the desktop software.

Here's my version.

Helpfully, just as I wrote this guide last weekend, Tableau completely overhauled the look and feel of the old Tableau Public site. Thanks guys. Suffice to say, there are share and download links on the web dashboard screen and you can also access your profile and any other dashboards you've uploaded. Have a browse around the site and all will become clear.

Tableau really is a fantastic tool and you can achieve amazing visualisations, much faster, than with anything else I've come across (and I reviewed quite a few). I love it and I hope these three posts will help to remove that initial trepidation for a few football analysts. Get stuck in, connect to data and start playing. You'll get it and if you don't, Google it. And if you still don't, feel free to tweet me @neilcharles_uk.

How to do football analysis in Tableau | Part 2

"Here's where the fun begins"
Han Solo

So you've read Part 1, you've downloaded and installed Tableau Public and you've got a small Liverpool and Everton dataset to play with. Or alternatively, you took the short cut, downloaded the dataset and came straight here.

Either way, it's time to hit Tableau.

Before you dive into the software, you'll need to create an online Tableau Public account. This will give you somewhere to publish your visualisations and also to save them while you work on them. One of the big restrictions of Tableau Public is that it's cloud-based and you can only save your stuff to Tableau Public's website

You've set up an account? Great, we'll make use of it later on. Now you can open up the Tableau Public software.

You should be looking at a screen like this...

Click "Open Data"and you get a long list of data sources that Tableau can access. The greyed out ones are for Professional users only - they aren't available in Tableau Public - but our dataset is in Excel, which is fine.

Click Excel, find your football data workbook and open it.

You should see Tableau's data loading screen.

You can do a lot of data manipulation here, including joining different datasets together, but we're just loading up a single Excel worksheet for now. If your Excel workbook has only got one worksheet in it, then Tableau will pick that up automatically. If you have more than one sheet in the workbook, then drag the one with the player data across from the left hand column to the empty top window.

Click "Go to Worksheet".

We're in! You should be looking at an empty Tableau worksheet.

If you can use Excel pivot tables then you're going to feel at home here quite quickly but if you can't then don't worry, it's all very straightforward.

Tableau's looked at our dataset and guessed which columns in our data are "Dimensions" and which are "Measures".

Dimensions are things you can split the data by. Player names, team names and positions go in here. "Apps" (number of appearances) shouldn't really be in here but we can deal with it later if we need that data. Tableau's guessed wrong because there are brackets for substitute appearances in the Apps column on our spreadsheet, rather than it just containing simple numbers.

Everything that isn't a Dimension, is a Measure. Measures are data columns that you want to add up, or average, or do whatever else mathematical with. Measures are your numbers. Tableau's put things like Age and Goals and Minuted Played in here, which is what we want.

So, what do you want to see first?

At last week's OptaPro Forum, Simon Gleave (@SimonGleave) showed some nice age distribution charts that plot the ages of players at a club. We could easily draw one of those.

Drag "Age" from the Measures area and drop it into the middle of the table, where it says "Drop field here". Take care to drop it in the middle, not onto the column or row headings areas.

If you're using the sample data, then it will now say 1,330 in the table. If you've put your own data together then you might get a different number because the WhoScored website is regularly updated with new player data.

1,330 is the total of all of the Everton and Liverpool players' ages in our dataset. Useful.

What about the average age of each team? That would be more useful.

Since you dragged in Age, there's now a green lozenge on the "Marks" area that says "SUM(Age)"

You can use this green lozenge to change from Sum to Average. Right click it, find "Measure (Sum)" in the popup and change it to Average,

In the sample dataset, the average age of all of Liverpool's and Everton's players is 26.6.

Let's split it by team. Drag "Team" from Dimensions onto the row shelf at the top of the screen and drop it.

Everton are older than Liverpool! We've just learned something.

Showing numbers to three decimal places is a bit much, so you can change the default formatting for Age if you want. Right click it in the Measures area, choose "Default Properties" and use "Number Format" - "Number (Custom)" to get rid of the decimals.

You could format numbers directly in the view but the nice thing about changing the default is that now whenever we use Age again, it will always appear without decimal places.

Stop reading for a minute and have a play with this table. It might seem odd to say it in a user guide, but the best way by miles to learn Tableau is to play with it. Drop more measures into the view and try splitting the rows and columns by different dimensions and see how Tableau reacts.

That's enough tables. Tableau's all about the graphics, no? Let's draw a chart.

Use the little tab button at the bottom of the screen - the one that looks like a little bar chart - to create a new empty worksheet. The other button - that looks like a little four pane window - is for creating dashboards. We'll get to that later.

Hopefully you're starting to see that in some ways, Tableau's a lot like Excel. It has worksheets and each worksheet is basically an Excel Pivot Table, with rows and columns and measures.

We're going to use this new sheet to draw an age distribution. That means we'll want to count how many players there are, split by age groups.

In our dataset, Age is a Measure to be summed or averaged, not a Dimension that you can split things by, but Tableau can sort that out for us. Drop age into the middle of the view, like you did before and then use "Show Me" to draw a histogram.

We've got a chart!

The Show Me button is the centre of Tableau and it's where you decide what kind of visualisation you want to draw. Think of it like the Excel Chart Gallery, but a lot more powerful.

Depending on what data you've dragged into the view, Tableau will offer you different types of charts in Show Me. This can sometimes get a bit confusing, e.g. you might decide to draw a scatter chart and Tableau says No and greys out the button. It looks at the data you've dragged into the main view and decides you can't draw a scatter with that.

When the type of chart you want is greyed out, look at the tip at the bottom of the "Show Me" box. Tableau will tell you exactly what it needs and when you drag those things in, the option you want will work. Once you start to get used to Tableau and the way that it works, you'll find this happens much less.

Charts in Tableau work exactly like tables and if you get confused, it can often help to think of them that way, or even switch back to a table, sort your data out and then switch back to a chart.

Charts working like tables, means that they have rows and columns and we can split our age chart by team if we want to.

Grab team from the Dimensions area and drop it just to the left of CNT(Age) on the Rows shelf.

Two charts! Now we can really see the differences in age that are driving Everton's older average.

Try dragging Team back off the Rows shelf and putting it in different places - on the Columns shelf, or into Colour or Label in the Marks area. There is loads of flexibility to create the view that you want.

Tableau has five basic ways of showing you differences in your data.

1. You can split it, using the Rows and Columns shelves.
When you do this, you'll get new rows and columns in a table, or new charts, one for each split.

2. You can vary colour

3. You can vary size
(That one doesn't really make sense as a team split - try it. Not every technique is good everywhere)

4. You can change the shape of datapoints

5. You can label different items

Tried all of those? Don't just skim through, I really meant it about playing being the best way to learn. Drag player names in. Swap Age for a different measure. Put team in Color and Label. Go nuts. Break stuff. Junk your worksheet and start again if you need to and remember that Tableau's Undo feature is pretty much bulletproof; Control-Z will always put things back the way they were!

Now that you know the basics of worksheets, you're ready to make your first dashboard...

We'll create some more charts and use them to build an interactive dashboard in Part 3.

How to do football analysis in Tableau | Part 1

I'm back from a hugely enjoyable OptaPro Forum last week and buzzing with new ideas. It was a fantastic day with some great presentations and it was brilliant to finally put faces to a few analysts' names (and Twitter handles!)

One question came up often enough at the forum to make me think that there might be an audience for this post. How do you use Tableau for football analysis...?

Want to know a secret? Tableau's easy. And it's free. There's really no need to restrict yourself to the purgatory of Excel's chart gallery. This post will cover a few basics and then if there's interest, I might do a follow up that shows how to do some more advanced visuals with X,Y pitch coordinate data.

I'm going to keep this post  (actually, since the length blew up as it was being written, these three posts) at a pretty high level: Where to get data, how to connect to it, how to draw some basic views and then make them interactive.

The guide will assume that you can handle yourself with the basics of copying and pasting and inserting columns in Excel and that "install this software; here's a link" isn't too taxing! In general, I'll try to take things step-by-step, with screenshots so you can see where we're going.

First things first, we're going to need a copy of Tableau. It comes in professional and free versions and unless you've got a grand to spare, you're going to want the free "Public" version. Tableau Public is almost fully featured, with just a few restrictions on the types of data you can load and how you save and export your dashboards (more on this later).

If you haven't already, download and install the latest version of Tableau Public from here.

Next, we'll need some data. Very often acquiring data and cleaning it up is the biggest barrier to football analysis and this post isn't going to cover the various sources you could use. Once you get into very large volumes of data, you start to need programming skills in a tool like Python or R and this is only supposed to be a basic intro! We need a small, simple dataset and WhoScored can help us out.

Let's build some visuals to compare Liverpool and Everton this season.

TL:DR. If you don't care about this bit, you can download the mini dataset that we'll use in Tableau and go straight to Part 2.

Go to the Liverpool page on WhoScored and you'll find a table that looks like this.

It's a nice little dataset with player statistics for this season, but it's not doing us any good stuck on the website - we need to extract that data.

There are a few automated tools that are worth trying for data extraction. Import.io is new and is shaping up to be a really great tool, but unfortunately it doesn't pick up the data that we're after when it scans WhoScored's web page. Excel's load data from web feature doesn't either.

We're going to have to do this the old fashioned way.

Click and drag to select everything from the little 'R' in the black title bar at the top of the table, to the bottom right hand corner of the data. Make sure you've got exactly that selected and then Control-C to copy.

(There are probably programmers yelling at their monitors right now. I'm not covering web scraping in this post!)

In Excel, hit paste (Control-V) in cell A1 and you get...

Now go and get the Everton data and do exactly the same thing, pasting it onto a different sheet.

Finally, copy the Everton data from Excel excluding the black titles row and paste it just below the Liverpool data. If you don't skip out the titles row, you'll get column titles mixed up with your player data in Tableau - we only need titles at the top of our table!

As a general rule, Tableau likes data to be in lists. You want your data to be listed downwards, not across the page as loads of columns. WhoScored's data is a list of players with facts about them and that's ideal - a separate set of columns for every player, or data scattered across different sheets won't work.

You can get rid of the Everton data sheet now, you don't need it any more. Give the worksheet with both teams on it a sensible name and save your workbook.

Now we're going to clean the data up a bit. We don't need all of the formatting, so highlight everything, find 'Clear' on the Home Menu (it's got a little pink eraser icon) and choose Clear Formats.

Simple black and white text. Proper analytics.

You could load your list of data into Tableau straight away, but it's still a little messy. Column B has got nothing in it, so highlight that whole column and delete it (Delete icon on the Home menu). The remaining data will move in from the right to fill the gap.

Those "-" signs indicating no data also aren't great for Tableau. Text saying "-" isn't no data, it's a cell with "-" in it. Find and replace "-" with nothing (Control-H) to get rid of them.

The last job in cleaning up is to sort out our player names. If you look in cell B2, you'll see that player names are currently mixed up with their ages and positions. The technical term for this is, "a pain in the arse".

Insert some columns to create a bit of space, starting from column C. Five columns should do it.

Now your data looks like this...

Highlight everything in column B and choose Text to Columns from the Data menu.

Choose "Delimited", tick "Comma" and click finish.

The positions data gets split into column C and because some players can play in a few positions, you'll get data in column D and maybe column E too. For this little project, we don't care about the extra positions, so delete columns D and E. Don't just clear the data out of them, delete them so that everything moves left and your data looks like this.

The playing positions are sorted, but our player's names are still mixed up with their ages. We can split these with a quick text formula.

Age is always a two digit number at the end of the name. Assuming no players are over 99 or under 10 years old, putting this formula in cell D2 will grab the player's age.

"Right" gets the two characters at the end of the text string and "Value" tells Excel to see the result as a number, not as text (e.g. 20, not "20").

The player's name is everything except the last two characters. Put this in cell E2 to grab that bit.

Copy and paste those two new formulas downwards, to fill up the table with names and ages.

You could have waited until Tableau to make these splits as it has exactly the same LEFT, RIGHT and LEN formulas as Excel, but I want you to be able to see the raw data table before we load it. Once you're in Tableau, the data table sits in the background and as a beginner it can sometimes be a little tricky to visualise what your formulas have actually done.

Nearly finished, I promise. If you look at your table of data, you'll notice that there's not a way to know which team each player is on. We've got a record at the top for Raheem Sterling, but it doesn't say "Liverpool" anywhere. That will limit us in Tableau because we won't be able to easily compare teams if that information isn't in our dataset.

The data in column A, labelled "R" isn't useful for anything, so let's put team names there instead. Select cells in column A down to the last Liverpool player, type "Liverpool" and hit Control-Enter to fill all of those cells. Then do the same for Everton and re-title column A as "Team".

The very last job is to add some column titles for the age, name and position columns you've created. Save your workbook and then if it looks like this, we're ready to hit Tableau in Part 2.