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A3, A3 thinking

A report prepared on a single sheet of paper (size 297 mm × 420 mm or approximately 11” x 17”) that adheres to the discipline of PDCA thinking as applied to problem solving that is called “A3 thinking.”

The problem solving A3 includes the background, problem statement, analysis, proposed corrective actions (and the action plan), and the expected results, often with graphics. A3 reports can be used as a standard method for summarizing problem solving efforts (e.g., analysis of Target Value Design options), status reports, and planning exercises.


How close the actual value of a quantity is to its specification (as distinct from precision).

→ related to predictability

Example: The painter’s duration estimate of 7 days plus-or-minus 2 days was accurate though not very precise: it took 8.5 days.

action research

Research that follows a progression of PDCA cycles while engaging in real world processes (rather than conducting isolated laboratory experiments).

G_action research cycle

Source: Action research cycle (adapted by Iris Tommelein from image posted on

The process starts with defining the issue by conducting initial observations and collecting existing data, then planning an intervention, then intervening, and ultimately analyzing and reflecting on that intervention as well as reporting out; it gets repeated over and over.


The taking of an action.

In the context of production management, action is taken in order to achieve an end such as achieving a recognizable state of completion or meeting a condition of satisfaction (as opposed, e.g., to reacting to some occurrence).

Activity is a general term used to avoid the specificity of, for example, use of the word task or step for example in the Last Planner System.

Activity Definition Model (ADM)

An input-process-output representation of work to be done in design or construction. The model depicts the specification of directives (entering the process rectangle from above), prerequisites (including materials and information to be transformed into the desired output, entering the process rectangle from the left), and resources (entering the process rectangle from below). It also shows an inspection process resulting either in redo or release to the customer process. The model is used as a guide to exploding scheduled tasks into a level of detail at which their readiness for execution can be assessed and advanced.


Image source: Jerry Talley

activity-on-arrow diagram (AOA)

Network drawn to support computations using PERT. It shows activities as arrows, delimited by event nodes.

This notation convention is the inverse of the activity-on-node diagram that is used in the Critical Path Method (CPM).

activity-on-node diagram (AON)

Network drawn to support computations using the Critical Path Method (CPM). It shows activities by means of nodes and precedence relationships by means of arrows.

This notation convention is the inverse of the activity-on-arrow diagram that is used in PERT.

Actual Cost (AC) [TVD]

The documented amount of money spent to actually perform work (an activity, chunk of work, or an entire project) based on the agreed definitions of cost, overhead, and profit.


→ see Activity Definition Model

advantage [CBA]

In the context of Choosing by Advantages, an advantage is the beneficial difference between attributes of two alternatives, one of which is the least preferred when assessed according to a certain criterion (after Suhr 1999).

Allowable Cost (AC) [TVD]

In Target Value Design, what an owner is willing and able to pay in order to get what they want, in other words, what that product or asset is worth to them.

alternative [CBA]

In the context of Choosing by Advantages, two or more people, things, or plans from which one is to be chosen (Suhr 1999).

anchoring [CBA]

In the context of Choosing by Advantages, the practice of basing decisions, attributes, and importance on (anchored to) relevant factual data (Suhr 1999).


Signal given by a production unit to alert others of the occurrence of a deviation from the standard and to possibly call for immediate help so that a countermeasure can be implemented without exceeding the Takt time and having to stop the assembly line.

Assembled To Order (ATO)

Product put together from parts that are already designed and made so as to meet the specifics of a customer request (order).

One category in a classification that distinguishes how long a product or service remains generic vs. becomes customer specific in its production.

One approach for mass customization, whereby parts may have been produced in volume based on forecast.

→ related to ETO, FTO, MTO, MTS, and CODP


Source: Iris D. Tommelein

assignment [LPS]

A request made to and accepted by a worker or workers (production unit) directly or indirectly producing (designing and making) something or offering a service.

In the Last Planner System, a request or offer that meets the quality criteria and has resulted in a reliable promise, ready to be placed on the Weekly Work Plan for performance.
Example: Scott, you and Julie are to make the changes in wall locations detailed in memo #123 by the end of the week. Anne, you find out what the building authorities will require for a structural permit.


→ see Assembled To Order

attribute [CBA]

In the context of Choosing by Advantages, a characteristic, quantity, or quality of one alternative (Suhr 1999).


“Intelligent automation” or “automation with a human touch” whereby a machine is made not only to fulfill its production function, but also to perform quality control functions, namely detect defects and automatically stop.

Autonomation helps to implement the jidoka principle (and pillar) in the Toyota Production System.