Standard +0.3 This is a straightforward one-tailed Poisson hypothesis test requiring students to set up H₀: λ=2.5 vs H₁: λ>2.5, scale to 4 weeks (λ=10), find P(X≥14) using tables, and compare to 5%. It's slightly above average difficulty due to the need to scale the parameter and interpret tables correctly, but follows a standard S2 template with no conceptual surprises.
2. The number of houses sold per week by a firm of estate agents follows a Poisson distribution with mean 2.5. The firm appoints a new salesman and wants to find out whether or not house sales increase as a result. After the appointment of the salesman, the number of house sales in a randomly chosen 4-week period is 14.
Stating your hypotheses clearly test, at the \(5 \%\) level of significance, whether or not the new salesman has increased house sales.
2. The number of houses sold per week by a firm of estate agents follows a Poisson distribution with mean 2.5. The firm appoints a new salesman and wants to find out whether or not house sales increase as a result. After the appointment of the salesman, the number of house sales in a randomly chosen 4-week period is 14.
Stating your hypotheses clearly test, at the $5 \%$ level of significance, whether or not the new salesman has increased house sales.\\
\hfill \mbox{\textit{Edexcel S2 2002 Q2 [7]}}