CyclingDeaths: London Cycling Deaths

In vcdExtra: 'vcd' Extensions and Additions

Description

A data frame containing the number of deaths of cyclists in London from 2005 through 2012 in each fortnightly period. Aberdein & Spiegelhalter (2013) discuss these data in relation to the observation that six cyclists died in London between Nov. 5 and Nov. 13, 2013.

Usage

data(CyclingDeaths)

Format

A data frame with 208 observations on the following 2 variables.

date

a Date

deaths

number of deaths, a numeric vector

Source

http://data.gov.uk/dataset/road-accidents-safety-data, STATS 19 data, 2005-2012, using the files Casualty0512.csv and Accidents0512.csv

References

Aberdein, Jody and Spiegelhalter, David (2013). Have London's roads become more dangerous for cyclists? Significance, 10(6), 46–48.

Examples

data(CyclingDeaths)

plot(deaths ~ date, data=CyclingDeaths, type="h", 
	lwd=3, ylab="Number of deaths", axes=FALSE)
axis(1, at=seq(as.Date('2005-01-01'), by='years', length.out=9), labels=2005:2013)
axis(2, at=0:3)

# make a one-way frequency table
CyclingDeaths.tab <- table(CyclingDeaths$deaths)

gf <- goodfit(CyclingDeaths.tab)
gf
summary(gf)

rootogram(gf, xlab="Number of Deaths")
distplot(CyclingDeaths.tab)

# prob of 6 or more deaths in one fortnight
lambda <- gf$par$lambda
ppois(5, lambda, lower.tail=FALSE)

Example output

Loading required package: vcd
Loading required package: grid
Loading required package: gnm

Observed and fitted values for poisson distribution
with parameters estimated by `ML' 

 count observed     fitted pearson residual
     0      114 117.946412       -0.3633792
     1       75  66.911907        0.9887681
     2       14  18.979820       -1.1430562
     3        5   3.589133        0.4108395

	 Goodness-of-fit test for poisson distribution

                      X^2 df  P(> X^2)
Likelihood Ratio 4.151738  2 0.1254474
[1] 2.854305e-05

vcdExtra documentation built on May 31, 2017, 4:57 a.m.