### Simple statistics can be good enough

Gaussian distributions are simple and easy to understand, but for some data such as rainfall and wind speed, they can result in physically impossible tails to negative values. Credit: Marek Uliasz / Alamy Stock Photo Study of the mismatch between spatial environmental data and a commonly used statistical analysis suggests simpler statistics are sufficient in…

### Innovative statistical methods shed light on extent of modern slavery in US, world

Policymakers, law enforcement and advocates can now better identify and target modern slavery thanks to the work of human rights experts and researchers whose application of unique statistical methods yields more precise figures on its existence and extent. The groundbreaking work appears in the October issue of Chance, which features a series of articles written…

### New tool predicts risk of plant disease and infestation worldwide

A newly developed technique can predict the risk of plant disease or infestation across the globe. Described in open-access journal Frontiers in Applied Mathematics and Statistics, the technique considers pest-host interactions and the geographical distribution of vulnerable plants to provide maps of potential disease hotspots. This could help governments to understand the risk of outbreaks…

### Did you solve it? Are you smarter than a Brazilian 15-year-old?

On my puzzle blog earlier today I set this question from Brazil’s State School Mathematics Olympiad Homero is clutching three identical pieces of string in his fist, as illustrated below left. He asks Sofia to tie two ends of the string, chosen at random, at either side of his fist, as illustrated below centre, so…

### Can you solve it? Are you smarter than a Brazilian 15-year-old?

Guzzlers, tudo bem? Here’s a question from Brazil’s State School Maths Olympiad, one of the largest and most remarkable maths competitions in the world. Founded 12 years ago by the Institute for Pure and Applied Mathematics in Rio de Janeiro, the Olympiad aims to improve maths education in the country’s cash-starved state school system. According…

### Want your child to be an engineer? Give them a falcon or go stargazing

A childhood brush with beekeeping, a foray into falconry or a fossil-hunting trip could inspire a new generation of much-needed engineers, scientists and mathematicians, new research suggests. Schools are being urged to consider introducing children to a hobby related to science, technology, engineering and maths – the so-called Stem subjects – after a major study…

### Six degrees of separation: Why it is a small world after all

Social network diagram. Credit: Daniel Tenerife/Wikipedia It’s a small world after all – and now science has explained why. A study conducted by the University of Leicester and KU Leuven, Belgium, examined how small worlds emerge spontaneously in all kinds of networks, including neuronal and social networks, giving rise to the well-known phenomenon of “six…

### Mathematically modeling HIV drug pharmacodynamics

3-D rendering of a colony of pathogen viruses. Credit: frenta / Masterfile 37 million people around the world today live with Human Immunodeficiency Virus (HIV), which is responsible for roughly 1.1 million deaths caused by AIDS-related conditions. The virus replicates by inserting itself into the genetic code of CD4+ memory T-cells, human immune cells essential…

### Scientists see order in complex patterns of river deltas

The world’s river deltas come in many complex and diverse patterns, as demonstrated by those depicted above (from top to bottom, left to right): the Lena (Russia), Mossy (Canada), Ebro (Spain), Niger (Nigeria), Amazon (Brazil), Ganges-Brahmaputra-Meghna (Bangladesh and India), Mekong (Vietnam), Wax Lake (Louisiana), Colville (Alaska), Parana (Argentina) and Mississippi (Louisiana) deltas. Yet nearly all…

### Can you solve it? The pain and pleasure of Japanese puzzles

Hi guzzlers Last column we played the Nikoli Derby, a Japanese game in which I asked you to submit the lowest number nobody else submits. The winner was 69. Honestly! It was such fun that we’re going play another round today, below. (Again, there’s a prize). Your strategy, however, may be different, since this time…