Relative entropy is a really cool tool that which haven’t heard of before you are in for a treat! Also known as Kullback-Leibler divergence, it is the measure of the distance between 2 probability distributions [e.g. p(x) and q(x) ] on a random variable X. It is defined as: Where H(P,Q) is the cross entropy…
Michael Betancourt recently wrote a nice case study describing the problems often encountered with gaussian mixture models, specifically the estimation of parameters of a mixture model and identifiability i.e. the problem with labelling mixtures (http://mc-stan.org/documentation/case-studies/identifying_mixture_models.html). Also there has been suggestions that GMM’s can’t be easily done in Stan. I’ve found various examples online of simple…
When publishing a paper on http://www.arxiv.org, here are some neat ways to make sure you maximise your impact. Getting to the top There has been research to suggest a correlation between the top Arxiv submission and the number of citations. As of 2017, Arxiv’s new submission deadline for the next day submissions is 2pm (EST), so in…
Its almost christmas and time to think about christmas presents. Below i list my top 10 christmas presents for the astronomy/space obsessed! 10. Time Travelling Toby and the Apollo moon landing by Graham Jones Graham Jones’ exciting take on the Apollo moon landings, this beautifully illustrated book is the perfect gift for those young kids (1-10)…
Ok this is going to be a really quick post and not much like my others but recently I met some fellow scientists and it wasn’t before long that our conversation steered towards that of space travel and in particular the prospect of a moon village. Now it would not be suprising to me if…
In today’s post I want to talk about the Exomars mission, what it’s all about, all the drama in the news and also the future of Exomars. For those that don’t know, ExoMars is joint mission between ESA (European space agency) and ROSCOSMOS (Russian space agency) to search for the evidence of life on Mars.…
Over the past year or so, I have been helping a small games company called Atomicom develop a new game. But how does a person like me fit into the gaming world? Well I was given the role of scientific advisor – simple task for a PhD in astrophysics right? think again. JCB Pioneer Mars is a…
