sim_min_max: sim_min_max

In inventorize: Inventory Analytics, Pricing and Markdowns

sim_min_max

Description

Simulating a min max policy or also called s,S policy, . The Function takes a demand vector, mean of demand ,sd,lead time and requested service level to simulate an inventory system, orders are lost if inventory level is less than requested demand, also ordering is made at day t+1, metrics like item fill rate and cycle service level are calculated. the min is calculated based on a normal distribution or a poisson distribution, also min can be set manually. Max - inventory position is ordered whenever inventory position reaches min

Usage

sim_min_max(
  demand,
  mean = FALSE,
  sd = FALSE,
  leadtime,
  service_level,
  initial_inventory_level = FALSE,
  min = FALSE,
  Max = FALSE,
  Max_to_min = 1.3,
  shortage_cost = FALSE,
  inventory_cost = FALSE,
  ordering_cost = FALSE,
  distribution = "normal",
  recalculate = FALSE,
  recalculate_windows = FALSE,
  plot = FALSE,
  Backlogs = FALSE
)

Arguments

demand	A vector of demand in N time periods.
mean	average demand in N time periods.default is FALSE and is automatically calculated. otherwise set manually.
sd	standard deviation in N time periods.default is FALSE and is automatically calculated. otherwise set manually.
leadtime	lead time from order to arrival (order to delivery time)
service_level	cycle service level requested
initial_inventory_level	integer,Default is False and simulation starts with min as inventory level
min	integer,Default is False and min is calculated based on mean,demand and lead time unless set manually
Max	integer,Default is False and max is calculated as a ratio to min,otherwise set manually.
Max_to_min	numeric, the ratio of Max to min calculation , default 1.3 but can be changed manually.
shortage_cost	numeric,Default is FALSE shortage cost per unit of sales lost
inventory_cost	numeric,Default is FALSE inventory cost per unit.
ordering_cost	numeric,Default is FALSE ordering cost for every time an order is made.
distribution	distribution to calculate safety stock based on demand distribution, current choices are 'normal' 'poisson','gamma' and negative binomial 'nbinom'
recalculate	Logical, if true the mean and sd is recalculated every period from first period to t,default is FALSE .
recalculate_windows	integer, the min mean and sd windows to recalculate , for example if it is set to 4 mean and sd is calculated from t to t-4,,default is FALSE, if TRUE, recalculate has to be TRUE Also.
plot	Logical, Default is False, if true a plot is generated
Backlogs	Logical, Default is False, if true inventory level accounts for previous lost orders

Value

a list of two date frames, the simulation and the metrics.

Author(s)

"haytham omar email: <[e-mail]>"

Examples

sim_min_max(demand = rpois(80,6),leadtime = 4,service_level = 0.95,recalculate = TRUE)

inventorize documentation built on June 1, 2022, 1:07 a.m.