Lean Glossary

Here are a few of the Lean terms you are likely to encounter

Alpha Risk Used in statistics to indicate the probability of accepting the alternative hypothesis when in reality, the null hypothesis is true
Autonomous Maintenance Component of Total Productive Maintenance. Basic preventive maintenance activities carried out by machine operators after training
Bar Chart A chart used to graphically summarise and display the differences between groups of data
Bartlett's Test A statistical test that determines an assumption of groups or samples having equal variance
Beta Risk Used to indicate the probability of accepting the null hypothesis when in reality, the alternative hypothesis is true
Box Plots A box plot, (also known as a box and whisker diagram), is a basic graphing tool that displays centering, spread, and distribution of a continuous data set
Brainstorming A technique for generating ideas. Most effective when undertaken as a group activity
Capability Study A process capability study uses both the process variability and the process specifications to determine whether a process is capable
Central Limit Theorem Statistical theorem that explains why many distributions tend to be close to the normal distribution
Characteristic Selection Matrix (CSM) A means used for prioritising Key Process Input Variables through to end customer requirements
Chi-Square Test Used to test if the standard deviation of a population is equal to the specific value
Confidence Intervals Means for stating numerically the level of confidence about a result
Contingency Table A chart used in the management of projects to help map the risks associated with the implementation of a plan.; A brainstorming activity that is followed by evaluation
Continuous Improvement (Kaizen) Continuous incremental improvement of aspects connected with a manufacturing process
Current State Map Detailed description of a current process
Critical to Quality Characteristic Element of a process or practice that has a direct impact on its perceived quality
Defects Per Million Opportunities A metric that can be compared across processes with varying levels of complexity. Converts to a sigma level by: number of defects divided by the number of defect opportunities multiplied by 1,000,000
Design of Experiments (DOE) A practical application of a statistical tool that enables low cost experimental methods to optimise the performance of products and processes during development.
Evolutionary Operations (EVOP) Experimental designs and improvements carried out whilst a process continues
Failure Modes & Effects Analysis (FMEA) Technique used to determine what chronic failures are occurring in a product or manufacturing/assembly process and the likely impact and frequency
Flexible Production and Manpower Systems Way of working that allows operators to move around different machines in response to changes in customer requirements
Flow Process Analysis (FPA) Analyses a process into a sequence of process elements in the order in which they occur
Flow Processing/Flow Production An efficient method of converting raw material into finished product eliminating or minimising transportation, handling of parts and work in progress
Frequency Diagram (Tally Chart) A means of displaying statistical information in order to show the relative frequency in which things (eg problems) occur
F-Test A test used to test various statistical hypotheses about the mean (or means) of the distribution from which a sample or a set of samples have been drawn
Future State Map Value Stream Mapping exercise which portrays the best practice process that sets the direction of mid-long term activities.  Creates a vision of how an ideal process would look like
Gauge Repeatability & Reproducibility Study A statistical method of assessing the amount of variation associated with a measurement system and comparing it to the total process variation
Histogram A chart used to graphically summarise and display the distribution of a process data set
Hypothesis Test A test based on statistical data, where you must chose between two alternatives
Key Performance Indicators (KPI) Chosen factors that directly and indirectly influence the effectiveness of a product or process
Lead Time Analysis Activity to identify the elements of lead time to measure how long a customer has to wait before receiving a product
Lead Time  The total time a customer, internal or external, must wait to receive a product after placing an order
Lead Time Profiles Activity to identify and quantify factors that determine how quickly a product reaches the next or end customer
Lean Manufacturing A business performance improvement tool that focuses on enhancing quality, cost, delivery and people.  Exposes waste and makes continuous improvement possible
Levelled Production A means of evenly distributing both the quantity and variety of parts across a production period avoiding overburden and under-utilisation in the workplace
Levene's Test An alternative to the Bartlett's test to determine if groups or samples have equal variance
Mean A statistic that measures the centre of a sample of data by adding up the data and dividing by the number of data points.  Commonly referred to as the 'average‘
Measurement Systems Analysis A process used to standardise the methods of analysis to ensure measuring systems used in process monitoring are fit for the purposes intended
Median A statistic that measures the centre of a set of data by ascertaining the value that divides the data in half ie the middle score
Metrology Study Activity to ascertain the effectiveness and accuracy of a measurement system
Mistake/Error Proofing (Poke Yoke) Means for eliminating defects by making a process robust to mistakes (foolproof)
Mode A statistic that is the most frequently occurring data value ie the result occurring more than any other result
Multi Variance Chart A simplified version of a box plot showing only the range
Normality Test Statistical tool for assessing whether the shape of a distribution is normal
One Way ANOVA ANOVA is an acronym for 'Analysis of Variance'.  An ANOVA separates different sources of variation seen in the experimental results
Overall Equipment Effectiveness Method of measuring and quantifying the performance of a machine being used to add value to a product
Pareto Analysis Based on the principle that states 'not all of the causes of a particular phenomenon occur with the same frequency or with the same impact'
Pareto Diagram A chart used to graphically summarise and display the relative importance of the differences between groups of data
Part Families A group of products that pass through similar processing steps and over common equipment
Parts Per Million Typically used in the context of defect Parts Per Million opportunities.  Synonymous with DPMO
Paynter Chart Type of pareto diagram where each Pareto bar is split up into subgroups.  Enables trends of trouble spots to be identified
Policy Deployment A method used to align all the constitutional parts of a company to face the same strategic direction
Process Capability (Cp and CpK) A statistical indicator that measures how close a process is running to its specification limits
Process Input Variables Work related elements of a process that can vary and therefore have an affect on a desired output
Process Output Variables Elements of a product or process requiring means of control to ensure a desired output meets specification
Process Capacity Table A table used to gather data on a product as it passes through all the processes in an area.  Can be used for production planning, equipment improvements and removing process bottlenecks
Process Mapping Method for depicting a process, material or information flow in a diagrammatic form.  Defines key process input and outputs
Pull System A customer driven work replenishment system involving 'pulling' the exact quantity of parts required out of a finished parts stores.  A Kanban issues the instruction to replenish the stock
Push System Description of the process involving manufacturers launching materials and components required to product goods according to a production plan
Quality Function Deployment A process that interprets and allows understanding of customer needs and expectations and product or service features and functions.  Translated as 'The voice of the customer‘
Representative Parts Groups of products that bear similar characteristics
Response Surface Methodology (RSM) A statistical method that uses quantitative data from appropriate experiments to determine and simultaneously solve multivarient equations
Right First Time Result of mistake free manufacturing process
Risk Priority Numbers (RPN) A figure that encapsulates the importance of the particular fault of failure. Calculated by the formula: Occurrence x Severity x Detection = Risk Priority Number
Root Cause The real cause or origin of a problem
Run Chart A simple plot of process characteristics against time or in a chronological sequence that is used to reveal trends or relationships between variables
Sigma A measure of variation from the mean which when applied to the business process represents the number of defects or failures likely to occur per million opportunities
Single Minute Exchange of Dies (SMED) (Set Up Reduction) Method for reducing tool changeover times facilitating increased capacity, smaller batch sizes, lower inventory and reduced lead times
Six Sigma A 'measure of goodness' involving the application of statistical methods to business processes to improve operating efficiency, reduce variation, avoid defects and reduce waste
Standard Deviation A statistical index of variability that describes the spread
Standard Operation Procedures (SOP) A step-by-step 'best current method' guideline aimed at reducing the variability of a process
State Map Diagrammatic and statistical representation of an entire manufacturing or design process
Statistical Process Control A standardising technique used for steering a process in a desired direction, reducing variation, increasing knowledge about the process, assessing process capability and providing performance benchmarks
Stem and Leaf Plot A display that shows the shape and distribution of a set of data
Supply Chain Map Diagrammatic identification of basic logistical and cost details in the supplier-customer procession
Taguchi Linear Graph A series of 18 'graphs' used to represent results of experimental designs undertaken to improve processes and products.  Can be used an an alternative to 'classical' DOE
Takt Time Takt is the German word for 'beat' and represents the pace at which the customer requires the product.  Takt time is the rate at which parts have to be produced to match the customer requirements
Time Series Charts Depict an orderly sequence of values of a variable at equally spaced time intervals that frequently occur when looking at process or product monitoring and control
Total Cost Model Diagrammatic representation of an activity to identify and evaluate all cost aspects connected with a particular product or process
Total Productive Maintenance Activity that targets zero downtime of machinery/equipment, zero defects and zero accidents by the pro-active identification of potential problems
T-Test A test that employs the statistic (t) to test a given statistical hypothesis about the mean(s) of a population
Value Stream A value stream is all the actions, (both value added and non-value added), that are required to bring a product through the main flows essential to nearly every product
Value Stream Mapping A pencil and paper improvement tool that provides an understanding of the flow of material and information as a product makes its way through the value stream
Value Management Process that establishes the most reliable performance which a product or process must do to make it work and sell at the least possible cost
Variance Deviation from a standard or norm
Visual Management Systems Enables the current situation in the workplace to be seen.  Examples of applications can be people, resources, inventory, tools, results and processes
Workplace Organisation Uncluttered and orderly management of the working environment
Zero Defects Manufacturing free from faults achieved by the elimination of errors in a product or process