Lean Six-sigma Certification Exam Graded A+

purpose of lean create value for customer by minimizing waste purpose of six-sigma reducing defects by conducting root cause analysis product of lean faster, more efficient and economical, satisfactory quality six-sigma's room for defect (DPMO) 3.4 defects per million opportunities (DPMO) origin of lean six-sigma lean came from ford but perfected by Toyota. six-sigma came from Motorola phases included in yellow belt exam define, measure, control 4 crucial benefits of lean six-sigma for organizations increase revenue, decrease cost, increase efficiency, develop effective people and teams which belts are part time and which are full time? yellow and green belts are part time whereas black belts are full time what are the 7 elements of waste (waste)? TIM WOOD transportation, inventory, motion, waiting, overproduction, over processing, extra-processing, defects 4 ways to handle waste (muda) ESSM: eliminate, simplify, streamline, minimize DMAIC stands for define, measure, analyze, improve, control modules included in define stage project charter, voice of customer, SIPOC modules included in measure stage select measures, data collection planning, operational definitions, baseline data modules included in analyze stage process analysis, brainstorm root causes, pareto charts, develop hypothesis modules included in improve stage create flow, mistake proofing, visual management and 5s modules included in control stage process monitoring and response plan, documentation and story board deliverables in define phase fully prepared team is formed and committed to work, customers identified and critical to quality characteristics (CTQs) defined, team charter developed, business process mapped. deliverables in measure phase Key measures identified, data collection planned and executed, process variation displayed and communicated, performance baselined, sigma level (variance) calculated. deliverables in control phase Documented and implemented monitoring plan, standardized process, documented procedures, response plan established and deployed, transfer of ownership (project closure). The Problem Solving Strategy Y = f(x) illustrates the idea that the important process outcomes Ys are a result of the drivers x's within processes what is a project charter? contract between organizations leadership and project team that outlines the problem/objectives, emphasizes senior management expectations, and establishes timeline and team member roles business case a document that uses the problem and the goal statements and converts it into a statement of business value a good problem statement should address these issues what, when, where, magnitude, impact a good goal statement should address these issues when, what, how, relevance types of project metrics operational (turnaround time, production time, number of defects) and financial (profitability ratios, sales figures) primary vs secondary metrics primary metrics are usually the most important critical to quality characteristic that measures what is desired, and secondary metrics are required to measure what is not desired or errors what is CTQ? critical to Quality factor is the quality of a product or service that is derived from the voice of the customer. A good CTQ should be measurable and include operational definitions and specific performance standards. cost of poor quality (COPQ) quantifies the negative outcomes (costs) due to waste, inefficiencies, and defects in a process; does not include detection and prevention cost. Financial Evaluation & Benefits Capture revenue, costs, market share, net present value (NPV), Return on investment (ROI) net present value (NPV) (future amount to be received)*(1+ annual interest rate)^(number of years) Return on investment (ROI) (Income / cost) * 100% importance in the voice of the customer important in guiding where to focus improvement efforts importance in the voice of the business provides clarity in identifying revenue growth areas, economic value added and market value. importance in the voice of the employee carries out the message and mission of the company six sigma hierarchy CEO, Champion, Master Black Belt, Black Belt, Green Belt, Yellow Belt yellow belt responsibilities A Yellow Belt typically has a basic knowledge of Six Sigma, but does not lead projects on their own. They are often responsible for the development of process maps green belt responsibilities work on small, carefully defined Six Sigma projects, requiring less than a Black Belt's full-time commitment. black belt responsibilities project team leader, allowing them to be directly responsible for projects within their organization. They are held accountable for the results. master black belt responsibilities identification of project deployment opportunities, highly skilled in communication, coaching, project management and statistical analysis champion black belt responsibilities ensure that whatever projects are undertaken mesh well with the goals and intentions of the business or corporation overall common internal customers HR and IT external customers people outside the organization that receive products and services stakeholders groups or individuals that might be impacted by process changes but they don't receive products or services main focus of define phase outline the issue and process to address process map using flowcharts to visualize and analyze the as-is process eclipse symbol on the process map means start/end point rectangle symbol on the process map means process point diamond symbol on the process map means decision point papercut symbol on the process map means document point trapezoid symbol on the process map means data collection point traingle symbol on the process map means storage point homeplate symbol on the process map means transport point circle symbol on the process map means inspection point SIPOC stands for supplier, input, process, output, customer what is SIPOC? high level map that defines the scope for process improvement activities by identifying potential gaps between suppliers and input specifications and between output specifications and customers expectations value stream map page documenting all the process used to produce and ship a product to the customer, both value-adding and nonvalue-adding processes correlation (quality function deployment) analytical chart identifying the relation between customer perception and design specifications Failure Modes & Effects Analysis (FMEA) qualitative and systematic tool to help anticipate what might go wrong with a product or process. In addition to identifying how a product or process might fail and the effects of that failure, FMEA also helps find the possible causes of failures and the likelihood of failures being detected before occurrence. FMEA key measures severity, frequency of occurrence and ease of detection risk priority number Severity x Occurrence x Detection importance of data collection understand how the process is performing and what parts of the process are contributing to the problem types of measures encountered in lean six sigma cycles time, days, size, dollars, attribute counts, defect counts importance of operational definition provides a clear and concise description of what is to be observed or measured, so that people taking or interpreting data will do it consistently importance of baseline data helps the team view the data from the customer's perspective and determines if the process is capable of meeting customer expectations how to classify data categorize data into continuous data which is quantitative or discrete which is qualitative possible distributions if data is continuous uniform, normal, exponential, chi sq (left skewed normal dist) possible distributions if data is discrete Binomial (affected by sample size and probability), Poisson (affected by mean) descriptive vs inferential data Descriptive statistics provide information about the specific data being analyzed, inferential statistics draw conclusions about a population how to tell if data is normal distribution? critical value test or normality plot importance of graphical analysis visualize and understand data in a graphical form to study significant relations among variables different types of graphs to represent data control chart, pareto chart, pie chart, histogram, scatter plot, box plot, matrix histogram A graph of vertical bars representing the frequency distribution of a set of data` control chart A graphic display of process data over time and against established control limits, which has a centerline that assists in detecting a trend of plotted values toward either control limit box plot A graph that displays the highest and lowest quarters of data as whiskers, the middle two quarters of the data as a box, and the median important data analysis values average, median, standard deviation, minimum, maximum, sample size Measurement system analysis (MSA) purpose create a measurement system to use by quantifying its accuracy, precision, and stability precision vs accuracy precision is consistency of output whereas accuracy is alignment with the targeted value or goal linearity (best fit line) consistency of bias over a range of measurements (example, if a bathroom scale is under by 1.0 pound when measuring a 150 pound person, but is off by 5.0 pounds when measuring a 200 pound person, the scale Bias is non-linear in the sense that the degree of Bias changes over the range of use) stability capacity of a measurement system to produce the same values over time when measuring the same sample Gage Repeatability & Reproducibility method for evaluating the variation in the measurement process. Allows for comparison, graphically and analytically, of process to measurement and specification to measurement variation variable vs attribute data attribute data shows go/no-go information (non-statistical) whereas variable data shows measurement information process capability the ability to meet design specifications, based on a sample of data taken from a process Cp equation (process capability) (upperlimit - lowerlimit) / (6*standard deviations) process stability vs process capability stability refers to consistency of the process with respect to important process characteristics whereas capability refers to the ability of the process to meet specifications process capability index adjustment of Cp for the effect of non-centered distribution Cpk equation (process capability index) (Zmin)/3 where Zmin = (upperlimit - mean)/ (3SD) or (mean - lowerlimit)/ (3SD) ,which ever is smaller A larger Cpk indicates the less likely it is that any item will be outside the specs Cp and Cpk levels that correspond to Four Sigma 1.33 process performance (Pp) capability of a process during its initial set-up, before it has been brought into a state of statistical control process performance index (Ppk) adjustment of process performance for the effect of non-centered distribution Cp > Cpk and Pp > Ppk Process is off-target but stable Cp > Pp and Cpk > Ppk Special (known) causes present Cp < Pp and Cpk < Ppk Certain fixed pattern in subgroup capability measure for discrete and attribute data capability measured in Defects per Million Opportunities (DPMO) purpose of the analyze phase determine the root causes of the problem and sources of waste opportunities to look for root cause in the process analysis rework loops, redundancies, bottlenecks, inspections and decisions, handoffs what are bottlenecks? design flawed places where the process is limited in the volume it can handle (shaped like a bottle neck) are inspections the solution to prevent defects? no inspections are non-value added work and adds to the cost of the system the five why's practice of asking why repeatedly in order to work the causal chain fishbone diagrams (cause and effect diagram) visual tool used to logically organize possible causes to specific problems by graphically displaying them in increasing detail importance of the Pareto analysis find the process that should be prioritized for improvement by ranking sources of problems by frequency of occurrence pareto 80:20 rule focusing on 20 percent of causes that result in 80 percent of the failures, instead of trying to attack all the problem causing factors, will have the best return on the effort and will be the most cost effective basic six sigma metrics DPU, DPO, DPMO, PPM, FPY, FTY, RTY Cycle Time DPU defects per unit or (total number of defects)/(total number of units) DPO defects per opportunity or (DPU)/(total defect opportunities) DPMO defects per million opportunities or DPU*million PPM parts per million or quantity of defective parts per million parts produced FPY (first pass yield) number of units coming out of a process divided by the number of units going into that process over a specified period of time. Rework or scrap are not counted as coming out of an individual process. FTY (first time yield) total number of acceptable product leaves the process when rework/scrap are counted, but only if the rework performed corrects the defects. 5 principles of lean define value, map the value system, create flow, establish pull, pursuit of perfection how to optimize flow? (river analogy) trying to remove parts where customer or subject is stuck in the process due to inefficiencies and bottlenecks ways to create flow batch size reduction, cross training, parallel processing and standard work serial processing process that is linear and sequential parallel processing process with steps designed to happen at the same time what does standard work consist of? consists of creating common procedures by using checklists, visual aids, templates, etc mistake proofing or poka-yoke reducing the likelihood of defect by eliminating the opportunity of error to occur in the first place hard mistake proofing (poka yoke) design process for error free execution