Conformity of census data
Before using Benford's law, it's important to check whether your dataset conforms to Benford's law. The dataset census.2009 contains the populations of 19509 towns and cities of the United States (July 2009) and was used in Nigrini, M. J. (2012). Benford’s Law: Application for Forensic Accounting, Auditing and Fraud Detection. Wiley and Sons: New Jersey. Let's test if the populations in 2009 satisfy Benford's law.
The plots will show the graphs and the legends separately, click Previous Plot to check the graphs.
Cet exercice fait partie du cours
Fraud Detection in R
Instructions
- Load the
benford.analysispackage. - Check the conformity of the variable
pop.2009to Benford's Law distribution of the first digit. Note that we only look at the first plot that is produced. The other plots are outside the scope of this course. - Multiply the variable
pop.2009by 3 and check the conformity again.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
# Load package benford.analysis
library(___)
data(census.2009)
# Check conformity
bfd.cen <- benford(___$___, number.of.digits = ___)
plot(bfd.cen, except = c("second order", "summation", "mantissa", "chi squared","abs diff", "ex summation", "Legend"), multiple = F)
# Multiply the data by 3 and check conformity again
data <- census.2009$pop.2009 * ___
bfd.cen3 <- benford(___, number.of.digits=___)
plot(bfd.cen3, except = c("second order", "summation", "mantissa", "chi squared","abs diff", "ex summation", "Legend"), multiple = F)