Target Capacity

Applies Kingman/Marchal's Formula :

 capacity = demand + (cvd**2 + cvc**2) / waiting_time

where cvd = coefficent of variation of time between arrivals cvd = coefficient of variation of sevice times waiting_time = target_wait / factor

Usage

calc_target_capacity(
  demand,
  target_wait,
  factor = 4,
  cv_demand = 1,
  cv_capacity = 1
)

Arguments

demand

Numeric value of rate of demand in same units as target wait e.g. if target wait is weeks, then demand in units of patients/week.

target_wait

Numeric value of number of weeks that has been set as the target within which the patient should be seen.

factor

the amount we divide the target by in the waiting list e.g. if target is 52 weeks the mean wait should be 13 for a factor of 4

cv_demand

coefficient of variation of time between arrivals

cv_capacity

coefficient of variation between removals due to operations completed

Value

numeric. The capacity required to achieve a target waiting time.

Examples

demand <- 4 # weeks
target_wait <- 52 # weeks

# number of operations per week to have mean wait of 52/4
calc_target_capacity(demand, target_wait)
#> [1] 4.076923

# TODO: Include a couple of standard deviations for errors in the mean demand