One of the most notoriously difficult subjects in statistics is the concept of statistical tests. We will explain the ideas behind it step by step to give you some intuition on how to use (and misuse) it, so read on…
Continue reading “From Coin Tosses to p-Hacking: Make Statistics Significant Again!”
The area of combinatorics, the art of systematic counting, is dreaded territory for many people, so let us bring some light into the matter: in this post we will explain the difference between permutations and combinations, with and without repetitions, will calculate the number of possibilities and present efficient R code to enumerate all of them, so read on…
Continue reading “Learning R: Permutations and Combinations with base R”
A few months ago I published a post on recursion: To understand Recursion you have to understand Recursion…. In this post we will see how to use recursion to fill free areas of an image with colour, the caveats of recursion and how to transform a recursive algorithm into a loop-based version using a queue – so read on…
Continue reading “Learning R: Painting with Fire”
There are a million reasons to learn R (see e.g. Why R for Data Science – and not Python?), but where to start? I present to you the ultimate introduction to bring you up to speed! So read on…
Continue reading “Learning R: The Ultimate Introduction (incl. Machine Learning!)”
Bavaria is known for its famous Oktoberfest… and within Germany also for its presumably difficult Abitur, a qualification granted by university-preparatory schools in Germany.
A mandatory part for all students is maths. This year many students protested that the maths part was way too hard, they even started an online petition with more than seventy thousand supporters at this time of writing!
It is not clear yet whether their marks will be adjusted upwards, the ministry of education is investigating the case. As a professor in Bavaria who also teaches statistics I will take the opportunity to share with you an actual question from the original examination with solution, so read on…
Continue reading “Was the Bavarian Abitur too hard this time?”
R is one of the best choices when it comes to quantitative finance. Here we will show you how to load financial data, plot charts and give you a step-by-step template to backtest trading strategies. So, read on…
Continue reading “Backtest Trading Strategies like a real Quant”
Tomorrow, on the First of May, many countries celebrate the so called International Workers’ Day (or Labour Day): time to talk about the unequal distribution of wealth again, so read on!
Continue reading “The Rich didn’t earn their Wealth, they just got Lucky”
Like most people, you will have used a search engine lately, like Google. But have you ever thought about how it manages to give you the most fitting results? How does it order the results so that the best are on top? Read on to find out!
Continue reading “Google’s Eigenvector… or how a Random Surfer finds the most relevant Webpages”
In this post we are talking about one of the most unintuitive results in statistics: the so called false positive paradox which is an example of the so called base rate fallacy. It describes a situation where a positive test result of a very sensitive medical test shows that you have the respective disease… yet you are most probably healthy!
Continue reading “Base Rate Fallacy – or why No One is justified to believe that Jesus rose”
One of the problems of navigating an autonomous car through a city is to extract robust signals in the face of all the noise that is present in the different sensors. Just taking something like an arithmetic mean of all the data points could possibly end in a catastrophe: if a part of a wall looks similar to the street and the algorithm calculates an average trajectory of the two this would end in leaving the road and possibly crashing into pedestrians. So we need some robust algorithm to get rid of the noise. The area of statistics that especially deals with such problems is called robust statistics and the methods used therein robust estimation.
Continue reading “Separating the Signal from the Noise: Robust Statistics for Pedestrians”