(a) Explain what you understand by the term sampling frame when conducting a sample survey.
(b) Suggest a suitable sampling frame and identify the sampling units when using a sample survey to study
the frequency with which cars break down in the first 3 months after being serviced at a particular garage,
the weight loss of people involved in trials of a new dieting programme.
(4 marks)
An ornithologist believes that on average 4.2 different species of bird will visit a bird table in a rural garden when 50 g of breadcrumbs are spread on it.
(a) Suggest a suitable distribution for modelling the number of species that visit a bird table meeting these criteria.
(b) Explain why the parameter used with this model may need to be changed if
50 g of nuts are used instead of breadcrumbs,
100 g of breadcrumbs are used.
A bird table in a rural garden has 50 g of breadcrumbs spread on it.
Find the probability that
(c) exactly 6 different species visit the table,
(d) more than 2 different species visit the table.