BIOGRAPHY Mr. John Wilder Tukey was born in 1915 in New Bedford, Massachusetts. He graduated from Brown University in 1936, with a bachelor’s degree in Chemistry. In the next three years of his life he would earn three degrees, one in chemistry at Brown University and two in mathematics as Princeton University. He became a Professor at Princeton at the age of 35, and in 1965, became the founding chairman of Princeton’s Statistics Department. John Tukey had a fascinating career that would eventually lead him to become one of the most renowned mathematicians in the world. He developed wide range theories and ingenious techniques to analyze masses of complex data and compute series of numbers quickly. Mr. Tukey died on July 26, 2000, in New Brunswick, New Jersey at the age of 85.
HIGHLIGHTS OF TUKEY’S CAREER Worked as a researcher at AT&T Laboratories Introduction to modern techniques for the estimation of spectra for time series Published “Exploratory Data Analysis” (Gave mathematicians new ways to analyze and present data) One of the tools is “The Stem-and-Leaf Display” Coined the word “software” before the founding of Microsoft. Chairman of a research committee that warned aerosol spray cans damaged the ozone layer
In 1973, awarded the National Medal of Science by President Richard Nixon First person to define the programs on which electronic calculators are ran. Termed the word “bit”, (binary digit) that describes 1’s and 0’s that are the basis for computer programs. 1960 to 1980 helped design the polls that the NBC television network used to predict and analyze elections Recommended that the census be adjusted by using statistical formulas in order to count poor urban residents who he thought were missed. MORE HIGHLIGHTS OF TUKEY’S CAREER
STEM- AND-LEAF PLOTS Definition: It represents data by seperating each value into two parts; the stem (leftmost digital) and the leaf (rightmost digital) Example: If you have some values – 59, 57, 60, 63, 62, 74, 77, 79, 80, 81, 101
Stem (tens) Leaf (units) 57,9 60,2,3 74,7,9 80,1 9 101 Note: The leaves are arranged in increasing order, not the order they occur in original list.
Advantage: 1.We can see the distribution of data. 2.We can reconstruct the original list of values by retaining all the information. 3.It is quick and easy to sort data, and sorting is required for statistical procedures (finding median and percentile).