Some Lean Six Sigma Tools - Define and Measure

The cost, speed and quality leaps of Lean Six SigmaOperational definition - various measures are defined
are obtainedthrough the application of appropriate tools.so that allteam members apply the same definitions
Following the DMAICimprovement model of Lean Sixwhen gathering data for theimprovement project.
Sigma, we will look at a number oftools from eachProcess map, value stream map, complexity value
phase.stream map:
The Define PhaseThis produces a more detailed representation of the
Purpose of Define:process thanthe SIPOC diagram and includes such
This phase of the Lean Six Sigma implementationinformation as wait times,processing times,
identifies theimprovement opportunities and customerresourceconsumptions, process operator etc.
deliverables and defines ascope. At the end of theCause Effect Matrix:
define phase, we should have a projectcharter, clearlyThis tabulates causes against effects and calculates
identified stakeholders, a project team,estimation ofscores whichare used to rank the causes. As a
business implications, an evaluation ofmeasuretool, this matrix is used to select which inputs
customerrequirements, a high level process map andto focus onbecause of their significant impact on the
project management andcommunication plans.process outputs.
Tools for Define:Preliminary FMEA (failure modes and effects analysis):
Stakeholder Analysis:This tool has a similar function to the cause and effect
The various stakeholders (customers, shareholders,matrix.
employees) arelisted and the potential impact of theAll possible failures in the inputs are considered, and
improvement project on each assessed as substantial,thenweighted accordingto probability of occurrence,
average, low or nil.severity of impact on outputs anddifficulty of detection.
SIPOC diagram:This assessment also helps to determinewhat inputs
Of the tools applied in this stage of the improvementthe project team should focus on.
project,perhaps the most commonly used is theData collection plan:
SIPOC diagram. SIPOC standsfor Suppliers, Inputs,This includes decisions as to what data (balanced
Process, Outputs and Customers. Thebetween input andoutput) to collect, identification
diagramprovides a visual answer to the questionsofstratification factors (these help determine patterns
required to understandthe process: who are thein the data),determination of sample size, identification
primary stakeholders of this process? Whatvalue doesof data sources,development of data collection sheets
it create? Who is the owner of the process? Whatand assignment of datacollection duties among team
are theinputs and who provides them? Whatmembers.
resources are consumed by theprocess? WhatPareto charts:
process steps create the value?This is one more tool for focusing the team's efforts
The steps involved in creating the SIPOC diagram andon the mostimportant problems. A Pareto chart is a
theinvolvement of team members in brain stormingbarchart where the horizontal axis represents
and idea generatingsessions are as important as thecategories. On thevertical axis we can plot in
resulting diagram.descending order, the frequency ofoccurrence, or cost,
VOC - Voice of the Customer:speed or quality impact of each category.
Critical to a proper definition of the improvementWhere a clear Pareto effect exists, only a few of the
project is theavailability of data representing customercategories
viewpoints andrequirements. These are collected using(typically 20% or less) are responsible for majority of
VOC tools like interviews,surveys, focus groups,the effects
comment cards, suggestion/complaint boxesetc. The(80% or more).
definition of customer here includes internal andMeasurement systems analysis:
externalcustomers.The process of obtaining measurements is subjected
Using Kano analysis coverts raw quantitative andto standard analyses to ensure reliability, repeatability
qualitative dataobtained from the above into clearerand reproducibility. Other attributes ofthe measurement
expressions of the valuecustomers place on varioussystem are stability, bias and discrimination.
product and service features you offer.Control charts:
Development of critical-to-quality requirementsA control chart is a run chart sequence of quantitative
converts customerstatements, which may bedata withthree horizontal lines showing a centred mean
imprecise, to precise requirements (valuedfrom theand upper and lowercontrol limits. Control charts help to
customer's perspective) for your product or service.assess the nature ofvariation of the process. In-control
The Measure Phaseprocesses are expected toyield data points randomly
Purpose of Measure:distributed around the mean but withinthe calculated
This phase quantifies the current state of the processcontrol limits.
with respectto cost, speed and quality and provides anProcess capability assessment:
idea of the gaps to befilled. At the end of this phase,This tool measures of process capability assess the
we have a detailed map of theprocess, data on keyability of aprocess to meet functional requirements.
input and output variables, an analysis of thecapabilitySeveral measures of capability exist. All of them are
of the process, refined project charter and planscompare theprocess standard deviation to the
wherewarranted by new information, andallowable range of variation asspecified by the
recommended actions to pick lowhanging fruits.customer.
Tools for Measure: