Who do you trust to build your synchrotron?

I love this clip of former Australian cricket Damien Fleming on the comedy show Thank God You're Here, the Australian theatre-sports style show which essentially aims to embarrass celebrities. In this challenge, as Australian sportsmen tend to talk a lot about things they don't know, Fleming was set the challenge of marketing the Australian Synchrotron. His opening line, "choosing the right sub-atomic particle analysis facility is a little bit like medium pace bowling" is brilliant. Check it out below or on the youtube video:

Science survival guide for The Ashes

Ashes backyard cricket
Originally uploaded by westius.

The sporting highlight of 2009 is only hours away. The Ashes cricket series between Australia and England will mean little sleep for cricket-obsessed Aussies, and little work done by the English.

Here is our science survival guide to the Ashes:

• Ashes success and El Nino

Is the winner of The Ashes already pre-determined? Manoj Joshi has shown that the El Nino Southern Oscillation (ENSO) phenomenon has a significant effect on the results of The Ashes cricket series when the series is held in Australia. The Australian Cricket team is more likely to succeed after El Nino years, while the English cricket team does better following La Nina years (the opposite phase). Their study, Could El Niño Southern Oscillation affect the results of the Ashes series in Australia? was published in the journal Weather.


• How to rank cricketers
  

Cricket is one of the world's most statistical sports, and mathematicians in cricket-loving nations love nothing more than delving into the minutiae of the numbers and diving into averages, strike-rates and custom-made measures of batting and bowling effectiveness.

For many people, including me, cricket isn't just a sport, it is a way of life.

These words could easily have come from me, but are actually the words of Rob Eastaway, a cricket-loving mathematician from the UK, and originator of the official International Cricket Council cricket-ratings which rank not only teams, but players within each team. In this podcast, I chat to Rob about how you mathematically rank cricketers.


• Science, Psychology and Cricket

Every cricket season, the TV coverage of cricket becomes more spectacular and technological, with the introduction of microphones to detect the finest of edges through to the keeper, improved abilities to determine the trajectory of a ball once it has left the bowler’s hand, and now even heat sensors to see how the batsman sweats.

But the scientific aspects of cricket are not limited to TV companies, with science playing an increasing role in shaping the performance of players, from their general fitness to specific training techniques for both their physical, and possibly more importantly mental, well-being. It is with science that countries are aiming to find the competitive edge.


• The curse of the duck

The recent news of the great Indian batsman Sachin Tendulkar surpassing West Indian Brian Lara's record number of test runs has given maths-loving cricket geeks another opportunity to pull out their calculators and Excel spreadsheets. At the time of writing, Tendulkar had scored 12,027 runs across 247 innings, to overtake Lara's 11,953 from 232 innings. After a little investigation, I found that despite his outstanding average of over 54 runs per innings, Tendulkar's most common score in test cricket is ... zero! Even the great Don Bradman scored a duck more times than any other score. And their next most common? One! We look at how are cricket scores are distributed.

• Science, Cricket, Fitness and Psychology

Do you need to be fit to play cricket? Do the best batsmen in the world really have the ability to predict the type of ball they will receive before it even arrives? And is cricket really more of a mental game than a physical one?

In this podcast episode, we talk to Dr Rob Duffield from the School of Human Movement at Charles Sturt University who has found that indeed you really do not need to be as physically fit to play cricket as you do other sports such as football. We also chat to Dr Allistair McRobert from Liverpool John Moores University whose work has shown that the best batsmen can predict to some extent where a bowler will bowl. This work encompasses a look into the subconscious mental game of cricket and how the most successful players are more mentally prepared for the top level than lesser players. More on this topic can also be found in our article The Science of Cricket.


• Sex before Sport?

It is the virile sports-person's eternal question - should one abstain from a little bit of nookie before a big sporting event? If I was Michael Clarke and engaged to Lara Bingle, I wouldn't be...


• Economists, oil, cricket and correlation

Can we predict cricket results using the price of oil? Or is this just bad stats. Also see our article Poor correlations, or why it's not the fault of Aussie cricketers.

Good luck to all and come on you Aussies!

Ep 108: Correlations of the week - vampires and zombies vs. presidents, cricket vs. the weather

This week on the podcast we tackle two Correlations of the week published recently here on The Mr Science Show:

1. Do the number of Vampire and Zombie movies released each year depend on whether the US president is Republican or Democrat?
   
2. Is the winner of the Ashes cricket series between Australia and England dependant on the El Nino effect?
   

Listen to this podcast here:

Correlation of the Week: Ashes success and El Nino

As we have shown on this blog a number of times (see here, here and here for starters), cricket fans love their maths. So it should come as no surprise that another cricket/maths story has recently come out, this time from the University of Reading linking cricket success with the weather! I only blog my maths/cricket geekiness, these guys have research funding!

Manoj Joshi has shown that the El Nino Southern Oscillation (ENSO) phenomenon has a significant effect on the results of The Ashes cricket series between Australia and England when the series is held in Australia. The Australian Cricket team is more likely to succeed after El Nino years, while the English cricket team does better following La Nina years (the opposite phase). Their study, Could El Niño Southern Oscillation affect the results of the Ashes series in Australia? was published in the journal Weather.

I didn't quite believe this at first, so I took their data, redid the maths, and it turns out that they are correct! However, the media interpretations of these results are not surprisingly a little over the top. Whilst there is a significant correlation between the state of El Nino in the year before the Ashes series and the result, the correlation itself is weak. This is an important point to keep in mind with any correlation - strength and significance are two different things - even sciencedaily got this wrong in its reporting on the topic. There is a nice explanation of these ideas here.

Strength refers to how well the data sets move with each other, significance refers to how likely it is the correlation occurred by chance. For example, you can easily get a strong correlation between two data sets if you have only a small amount of data. But as you lack data, it is unlikely that the relationship will actually be significant. In our case however, the correlation is quite weak, but the relationship is significant. The conclusion to this study should be that ENSO plays a very small role in determining the results of Ashes series in Australia, but that other factors are likely to be more important, and that simple noise and randomness will probably have more of an effect than the phase of ENSO. It is only over time that this correlation can be teased out. The study does admit this, with Joshi saying:

"There are of course many different factors governing the outcome of any given sporting contest, which would act as noise in this analysis."

But I think his statement that "the study could even influence whether the England touring team should include more fast bowlers or more 'swing' bowlers" is probably a little bold (and to his credit he does admit this)!

So, how does this all work?

There are two phases of ENSO - during El Nino, the eastern equatorial Pacific Ocean warms by about 1 degree. For Australia this means low rainfall and high temperatures. La Nina is a reverse, with more rain and a drop in temperature. The study analysed the results of all Ashes matches held in Australia from 1882-2007 and found that during El Nino years, the Australian team won 13 out of 17 series (76%), but only five out of the 13 played in La Nina years (38%). England has only won one Ashes series in the last 100 years following an El Nino event - the Bodyline series in 1932/33. The author speculates that cricket pitch conditions can affect the outcome of a match with the drier pitches of El Nino favouring fast Australian bowlers with the English slower swing bowlers enjoying La Nina.

Now to the maths. I have reproduced the results from the paper in our chart as you can see here. On the y-axis is the series result (English wins minus Australian wins). On the x-axis is the Nino 3 index, which is the mean monthly temperature anomaly in the eastern tropical Pacific: 5S-5N; 150W-90W. Of course, all the dots should be on integer values of y - some were shifted in the original paper for ease of viewing. The correlation is still correct.



What we can see here is a very weak correlation - the R² value is only 0.1. R² is the coefficient of determination and gives some information about goodness of fit. A value this low is generally accepted as suggesting no correlation at all. One interpretation is to say that about 10% of the correlation can be explained by the Nino 3 index. The paper itself quotes R (=-0.31) as opposed to R², but to determine whether a relationship is strong or not, you need R².

To test for significance, Joshi generated 10000 sets of randomly generated numbers to represent the Nino 3 index - each set had 32 members (the same number as the number of Ashes series) and a normal distribution with a mean of zero and a standard deviation of 0.8, similar to ENSO observations. They found that the chance of R being more negative than -0.31 was 5%, which is the level generally accepted as being significant.

There is, however, an easier way to do this - you can use t-tests (as we used in our earlier Correlation of the Week on vampire and zombie movies). To generate your t-statistic, you use the formula:

where N is the number of sample points (32). When you do this, you get a t value of -1.78. This means that if our null-hypothesis is r=0 (that is, there is no correlation), when you look this t-value up in a t-distribution table, you find that it is more negative than the critical value of -1.70 in a one-tailed test, which means it is significant. What all this means is that there is a very weak significant correlation very close to zero. I wouldn't put any money on either team based on this result! In any case, Australia is going to win....

Beauty and the Geek comes to Australia

Ever seen the American show Beauty and the Geek, produced by twitterer, actor and producer Ashton Kutcher? The show takes a bunch of horribly awkward, socially inept, level-23 dragon overlords - sorry, Dungeons and Dragons aficionados - and puts them in a house with a group of stunning looking, but generally slow-on-the-uptake, girls to see what happens. Each geek is teamed up with a beauty and they live together in a room throughout the show, with challenges in each episode being used to eliminate the couples. The challenges test what the contestants are bad at - the beauties are tested in academic topics (the geeks are supposed to tutor them) and the geeks are tested with social questions (the beauties are likewise supposed to teach them about the real world). At the end of the show, one couple wins a swag of money and there is a very American resolution with the contestants saying how much they've learnt and grown.

So yes, it's ridiculous and patronising - but it's compelling viewing and coming to Australia!

If you want to apply to be a contestant on the show, download the application forms on the Channel 7 Beauty and the Geek website.