@CharlieTheo

Virtual water and the value of it I was made aware of this book during revision zoom call and I began reading without a clue about the concept or its importance.  I was a little disappointed that I had to order the book twice, the first being from Amazon where the printing was completely off and I could only read 3/4 of each page!  However, I found a second hand version so I hope this has now been addressed by the Amazon distributer. The concepts of blue water, green water and the way water may be traded goes beyond the specification of my current studies, however the book takes you on a story from explaining the concept and its origins to its possible future applications. Tony Allan at the time of writing was pessimistic about whether his publication will impact the current geopolitics that are destroying the delicate balance of the global hydrological cycle.  Sadly, little has changed in the last 10 years with our obliviousness to the way we trade this "embedded water" ...

What is xG and why is everyone so interested in it? I first saw this on Twitter with an “xG” scoreline being posted for a Manchester United game I was watching.  That day, I gave it a follow so that I could brag about how I was following it before it was cool, without never really knowing what it meant! A year or so went by and it ended up slowly fighting its way into the public eye after a Jeff Stelling rant and a Mikel Arteta press conference. It was at this point I found myself thinking ‘I don’t really know what it is!’  So I eventually took matters into my own hands a month later and ordered the book. I was not particularly for or against this method of analysing football matches, but I was intrigued as to how it is calculated.  I will be splitting my review into two parts: "what is xG?" and "how useful is xG?". So, answering the first big question - "what is xG?".  The name stands for expected goals, and this is equivalent to the chance of the "a...