V2 Missile Hits in London

A small count data set. During WWII V2 missiles were fired from the continent mainly towards London. The number of hits per square grid around London were recorded.

Usage

data(V2)

Format

A data frame with the following variables.

hits

Values between 0 and 3.

ofreq

Observed frequency, i.e., the number of grids with that many hits.

Details

The data concerns 408 square grids each of 0.25 square kms about south London (south of the River Thames). They were picked in a rectangular region of 102 square kilometres where the density of hits were roughly uniformly distributed. The data is somewhat comparable to V1 albeit is a smaller data set.

Source

Shaw, L. P. and Shaw, L. F. (2019). The flying bomb and the actuary. Significance, 16(5): 12–17.

See also

V1, poissonff.

Examples

V2
#>   hits ofreq
#> 1    0   356
#> 2    1    41
#> 3    2    10
#> 4    3     1
mean(with(V2, rep(hits, times = ofreq)))
#> [1] 0.1568627
 var(with(V2, rep(hits, times = ofreq)))
#> [1] 0.1964638
 sum(with(V2, rep(hits, times = ofreq)))
#> [1] 64
if (FALSE)  barplot(with(V2, ofreq),
          names.arg = as.character(with(V2, hits)),
          main = "London V2 rocket hits",
          col = "lightgreen", las = 1,
          ylab = "Frequency", xlab = "Hits")  # \dontrun{}