Kidney Stones & Simpson's Paradox

A new look at an old research study In 1986, a group of urologists in London published a research paper in The British Medical Journal that compared the effectiveness of two different methods to remove kidney stones. Treatment A was open surgery (invasive), and treatment B was percutaneous nephrolithotomy (less invasive). When they looked at the results from 700 patients, treatment B had a higher success rate. However, when they only looked at the subgroup of patients different kidney stone sizes, treatment A had a better success rate.

Using Math to Draw Flowers

Patterns in nature “A scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful” - Henri PoincarĂ© There are many examples of natural facts that can be described in mathematical terms. Nice examples are the shape of snowflakes, the fractal geometry of romanesco broccoli or how self-similarity rules the growth of plants. R is a tool for doing serious analysis, but not everything in life is serious.

Human Variability in Computer Input Device

Computers are ubiquitously used in a number of jobs and even at home as an aid to facilitate various tasks. Operation devices are used to transfer information to machine and adjust or change the state of machine [1]. Most interaction with a computer involve using either mouse or a keyboard. People most often maintain static, unnatural posture for long hours. Using the mouse means repetitive movements which may cause physiological problems in the arm, wrist and shoulder [2].


Sentiment analysis is about detecting emotions, opinions of people about certain topics by analyzing their texts from tweets, fb comments or status , youtube comments so on and so forth. Retail industries and companies in general use sentiment analysis to get an overview of their clients’ opinions on their products which enables them to make improvements and certain modifications to their products so that it meets their clients’ standards. There are a lot of social media sites like Google Plus, Facebook, and Twitter that allow expressing opinions, views, and emotions about certain topics and events.

Dr. Semmelweis and the discovery of handwashing

Dr. Ignaz Semmelweis was a Hungarian physician born in 1818 and active at the Vienna General Hospital during the 1840s. In 1847, the Ignaz Semmelweis made a breakthrough discovery: he discovered handwashing. Contaminated hands were a major cause of childbed fever and were often fatal by enforcing handwashing at his hospital he saved hundreds of lives. Childbed fever was a deadly disease affecting women that just have given birth. In Vienna General Hospital’s First Obstetrical Clinic, doctors’ wards had three times the mortality of midwives’ wards.

Wrangling and Visualizing Music Data

Introduction How do musicians choose the chords they use in their songs? Do guitarists, pianists, and singers gravitate towards different kinds of harmony? We can uncover trends in the kinds of chord progressions used by popular artists by analyzing the harmonic data provided in the McGill Billboard Dataset. This dataset includes professionally tagged chords for several hundred pop/rock songs representative of singles that made the Billboard Hot 100 list between 1958 and 1991.