Choosing the right member is a piece of cake
by Massimiliano Zappa, a HEPEX 2015 Guest Columnist
Dear all, I was somehow convinced by the maintainers of this nice blog to make myself available as guest columnist for 2015. The task will be rather challenging since the predecessors in 2014 did a really nice job and compiled a series of interesting contributions. This convinced me to join Twitter and follow all the additional stuff emerging from @hepexorg.
Back to the 2014 columns, it was quite a comprehensive and well balanced mixture of interviews, presentation of current work, opinions and “political” statements. If I have to look back, two posts come first to my mind: the “gender balance post” by Bettina Schaefli, and the “11th advice post” by Anders Persson. You can comment here below about your favorite posts by the 2014 columnists. No matters what you will choose, no post will be superior to the one published by Mc Fools’. I am still waiting for his second post. If he (or she) is reading: “Do you have Twitter? I want to follow you!”
So, a long introduction to come finally to the content of my first guest columnist post. Please read it to the end, even if it is getting lengthy…
The three kings cake problem
Some of us have this problem once a year on January 6th (Three Kings Day). Now, if you can look at the picture here below without getting hungry, you have already a problem less than I do with it (by the way this was my Home-made Three Kings Cake in 2014). The second part of the problem has of course an obvious link with HEPEX, while otherwise it would not make any sense to present this here. Our 2014 cake had 8 small pieces of bread and a big bread in the center. In one of the small breads a figure is hidden (usually a king, but recently also female figures are found, just to come back to the gender balance issue). The person selecting the right small bread will be king (or queen) for the next few days. There is little knowledge about a priori distribution. What is quite sure is that the figure is NOT in the big central bread (only if someone manipulated it). Another fact is that in the last 6 years my daughter won it 4 times and my son 2. There is some evidence that young participants have a bigger chance to win (for sake of peace within the family, you might argue …). How can I prevent this?
[Here a recipe]
|Now, the funny part is coming. I talk now about the second figure here below, and for that I re-arrange the text I just wrote about the first figure (differences are underlined and in italic, some links to past posts are hidden).
The ensemble flood forecast problem
Some of us have this problem every now and then when the spread of their real-time forecast is high. Now, if you can look at the picture here below without being responsible for an alert, you have already a problem less than I do with it (by the way this was our Home-made forecast on December 15th 2014). Our forecast has 16 members and we plot the median in the center. The users expect that one of the members is THE correct forecast, and he (or she) thinks we should know which one it is. The person taking the right decision will be king (or queen) for the next days (see also a previous post). There is little knowledge about a priori distribution. What is quite sure is that the right decision is NOT in the median (only if someone post-processed it perfectly). Another fact is that in the last 6 years (our operational system runs since 2008) my end-users where quite happy with the system, but still ask me about telling them the RIGHT member. There is some hope that young scientists will join HEPEX and contribute to this fascinating science and come closer to give the users an adequate answer to their expectations (it is maybe utopic, you might argue …). How can we facilitate this?
[Here a recipe]
I wish all of you a nice start in 2015 and that you can choose the RIGHT piece of cake and give the RIGHT support to your end user.
PS: I will put in a comment an update of the statistics within my family. Cross fingers …
Massimiliano Zappa is a HEPEX 2015 Guest Columnist.