There are seven deaths by day 28. Their total time plus 28 days from each of the ten later observations gives first-interval exposure
$$
T_1=120+10\times28=400,
\qquad
\widehat\theta_1=\frac7{400}.
$$
Among the ten observations beyond day 28, eight are deaths, and their exposure beyond 28 is
$$
T_2=2080-10\times28=1800,
\qquad
\widehat\theta_2=\frac8{1800}.
$$


Solution

Past exam of the mathematics course of the University of Cambridge / 2026 / iii / Paper 207 / 6 / c / i / Solution

 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2026/iii/paper-207/6/c/i/solution