The final lesson states the boundary: this is deterministic card-count arithmetic.
Deterministic rule
The rule sizes cards from exact demand, lead time, safety factor, and container size.
deterministic sizing rule \text{deterministic sizing rule} deterministic sizing rule Safety-factor comparison The chart compares the base policy safety factor with a zero-safety what-if. safety-factor comparison lead-time demand 20 x 2 = 40 safety allowance 40 x 1/4 = 10 protected demand 50; container 10 base: protected 50 K1 K2 K3 K4 K5 5 cards what-if 1: protected 40 K1 K2 K3 K4 4 cards case safety lead demand safety allowance protected cards base 1/4 40 10 50 5 what-if 1 0 40 0 40 4 deterministic sizing rule with a policy safety factor
Policy factor
The safety factor is a policy choice, so changing it changes the card count.
5 cards vs 4 cards 5\text{ cards vs }4\text{ cards} 5 cards vs 4 cards Safety-factor comparison The chart compares the base policy safety factor with a zero-safety what-if. safety-factor comparison lead-time demand 20 x 2 = 40 safety allowance 40 x 1/4 = 10 protected demand 50; container 10 base: protected 50 K1 K2 K3 K4 K5 5 cards what-if 1: protected 40 K1 K2 K3 K4 4 cards case safety lead demand safety allowance protected cards base 1/4 40 10 50 5 what-if 1 0 40 0 40 4 deterministic sizing rule with a policy safety factor
Not modeled
It is not a stochastic service guarantee, scheduling proof, or queueing proof.
outside scope: service guarantees and queues \text{outside scope: service guarantees and queues} outside scope: service guarantees and queues Safety-factor comparison The chart compares the base policy safety factor with a zero-safety what-if. safety-factor comparison lead-time demand 20 x 2 = 40 safety allowance 40 x 1/4 = 10 protected demand 50; container 10 base: protected 50 K1 K2 K3 K4 K5 5 cards what-if 1: protected 40 K1 K2 K3 K4 4 cards case safety lead demand safety allowance protected cards base 1/4 40 10 50 5 what-if 1 0 40 0 40 4 deterministic sizing rule with a policy safety factor
Honesty note
Kanban card count is a deterministic sizing rule with a policy safety factor. It is not a stochastic service guarantee, scheduling proof, or queueing proof.
deterministic card-count arithmetic only \text{deterministic card-count arithmetic only} deterministic card-count arithmetic only Safety-factor comparison The chart compares the base policy safety factor with a zero-safety what-if. safety-factor comparison lead-time demand 20 x 2 = 40 safety allowance 40 x 1/4 = 10 protected demand 50; container 10 base: protected 50 K1 K2 K3 K4 K5 5 cards what-if 1: protected 40 K1 K2 K3 K4 4 cards case safety lead demand safety allowance protected cards base 1/4 40 10 50 5 what-if 1 0 40 0 40 4 deterministic sizing rule with a policy safety factor