Present value for each uptake cohort and calculation time

Calculates the sum of the Present Value by uptake cohort (j) and time at which the calculation is performed (tzero input to dynpv())

Usage

sum_by_coh(df)

Arguments

df

Tibble of class "dynpv" created by dynpv() or futurepv()

Value

A number or tibble

Details

The Present Value of a cashflow \(p_k\) for the \(u_j\) patients who began treatment at time \(j\) and who are in their \(k\)th timestep of treatment is as follows $$PV(j,k,l) = u_j \cdot p_k \cdot R_{j+k+l-1} \cdot (1+i)^{2-j-k}$$ where \(i\) is the risk-free discount rate per timestep, \(p_k\) is the cashflow amount in today’s money, and \(p_k \cdot R_{j+k+l-1}\) is the nominal amount of the cashflow at the time it is incurred, allowing for an offset of \(l = tzero\).

This method returns \(\sum_{k=1}^{T-j+1} PV(j,k,l)\) for each value of \(j\) and \(l\), where \(T\) is the time horizon of the calculation.

See also

dynpv(), futurepv()