One day when I spent some day in the smallest room of my company, I really got annoyed by the toilet paper getting ripped off after the first piece of paper. Maybe you have also experienced this, especially when a toilet paper dispenser like the one shown below is involved.
Toilet paper dispenser showing unpleasant behaviour
There is kind of an unwind impediment integrated in these dispensers which makes you pull hard on the loo paper. That’s why it becomes so evident that the position where the toilet paper breaks is influenced by how you pull it. Anyway, the following explanations account for usual toilet paper consumption as well 😉 more →
Integration by substitution (often referred to as u-substitution) is quite hard to understand. Most people just follow their proven recipe when performing this kind of integration. In contrast to that doing, I want to illustrate why the steps of u-integration are necessary. Therefore we will develop the idea slowly by giving simple examples which illustrate what works and what doesn’t. more →
Those of you who already have tested for the variance of data from a normal distribution may have asked themselves how the link between normal variance and chi-squared distribution arises. Trust me: The story, which I will tell you, is an exciting one! more →
My dad told me that a car’s fuel economy is bad in winter, because the engine has to heat a lot more. Well, I read about cold engines, low tire pressure, higher rolling resistance and so on. They didn’t convince me. All together have a substantial impact, I admit, but the most important factor of fuel consumption is not discussed sufficiently! more →
Imagine you drive in your car against head wind and later you return with tail wind. When asked, most people tend to say that the force of the wind on average equals the situation when there is no wind at all. This is surprising since the same people will tell you that the air resistance (the aerodynamic drag) increases as the squared velocity increases. I will show you why wind is substantial when discussing causes of high fuel consumption! more →
Having a model to predict the performance of a share would be great, wouldn’t it? In this article I will show that such a model indeed exists. From a statistician’s point of view, the rate of stock return follows a particular probability distribution (which is also one of the preconditions of the Black-Scholes model). Assuming that parameters remain stable over a period of time, we can also give probabilities for some rates of stock return. Got curious? more →