In: Statistics and Probability
A particular area in a town suffers a high burglary rate. A
sample of 100 streets is taken,
and in each of the sampled streets, a sample of six similar houses
is taken. The table below
shows the number of sampled houses, which have had burglaries
during the last six months.
No. of houses burgled x | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
No. of streets f | 39 | 38 | 18 | 4 | 0 | 1 | 0 |
(i) (a) State any assumptions needed to justify the use of a
binomial model for the number of
houses per street which have been burgled during the last six
months.
(b) Derive the maximum likelihood estimator of X bar, the
probability that a house of the
type sampled has been burgled during the last six months.
(c) Determine the probabilities for the binomial model using your
estimate of X bar, and,
without doing a formal test, comment on the fit.
(ii) An insurance company works on the basis that the
probability of a house being burgled
over a six-month period is 0.18. Carry out a test to investigate
whether the binomial
model with this value of p provides a good fit for the data.
NOTE:THERE WAS A MISTAKE ON (b) IT IS ESTIMATOR OF X BAR NOT ESTIMATOR OF P but i have corrected it