DMAIC Problem Solving Process
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QETools Tutorial - Part I QE Tools Software Tutorial An Excel-based Statistical Software Add-In for Lean-Six Sigma qetools.com Topics Note: Not all tools are shown in this tutorial. See help files for additional examples. 2 1 www.qetools.com QETools Tutorial - Part I Topics (Continued) 3 QE Tools Menu of Tools 4 2 www.qetools.com QETools Tutorial - Part I QE Tools Tutorial Part 1 – Getting Started and Data Manipulation 1.1 Getting Started 1.2 Data Manipulation Tools Subset Data Split Data by Group 1.3 Six Sigma Methods – Tool Roadmap qetools.com 5 1.1 Getting Started Excel Menu QE Tools appears as a menu option in the main Excel toolbar 6 3 www.qetools.com QETools Tutorial - Part I 1.1 Getting Started New Data Sheet QE Tools uses a dedicated data sheet (own worksheet) for performing analyses. Begin by creating an initial blank datasheet using the New Data Sheet menu pick. 7 1.1 Getting Started Data Sheet . A new, pre-formatted worksheet is inserted with name “Datasheet” (Warning: Do not change sheet name). After you create a data sheet, you can add and manipulate data in ways familiar to you in Excel (e.g., copy, paste, add formulas, etc.) . Note: You must define a variable name for each data series (Datasheet Row: “Var Name”) . Optional, may include Upper and Lower specification Limits (USL and LSL) as well as a Target (nominal) value for each variable. These will automatically be referenced for those tools that use specification limits for analysis. TIP: Use Datasheet to only store raw data 8 4 www.qetools.com QETools Tutorial - Part I 1.1 Getting Started Macro-Enabled File Format Be sure to save the file as a “.xlsm” macro- enabled format file to ensure the QETools functionality works properly 9 1.1 Getting Started Entering Data – “Datasheet” . If all data in a column are numerical values, QETools will recognize as “Data” in the “Var Type” row. Otherwise, data will be listed as “Text.” . Important: Certain tools are restricted to the use of Data Variables Only. Note: You may also copy data from other locations (e.g., Excel File). TIP: Do not copy entire worksheet. First rows on data sheet are reserved for data characteristics 10 5 www.qetools.com QETools Tutorial - Part I 1.1 Getting Started Data Format in “DataSheet” . Variables may include Text or Data Variables . Data variables may either be values or calculations (Excel Formulas). Examples: • ‘TotalVisit’ has data values • ‘TotalWait’ and ‘WaittoVisit’ are formula. Data for any variable may be constructed using standard Excel commands. 11 1.1 Getting Started Variable Names When entering variable names, QE Tools may update after you enter them or paste from another worksheet QE Tools uses an algorithm to standardize variable names: Certain characters are not allowed in variable names and are removed: ":", "\", "/", "?", "*", "[", "]", "'", " ", "(", ")", "`", "~", "@", "#", "$", "%", "^", "&", "-", "+", "=", "{", "}", "|", "<", ">") Duplicate names are not allowed to insure QE Tools knows which variable you wish to analyze when running a tool 12 6 www.qetools.com QETools Tutorial - Part I 1.1 Getting Started Number of Worksheet Warnings QETools warns of too many active worksheets because performance may be diminished with increasing file size After 30 worksheets, QETools issues a warning message Recommend creating a second analysis file or removing unused worksheets 13 1.2 Data Manipulation Sorting and other data manipulation may be done using normal Excel Functionality, OR QE Tools has a data manipulation tool for: Subset Data by Variable Split Data Set by Variable 14 7 www.qetools.com QETools Tutorial - Part I 1.2 Data Manipulation Subset Data – Dialogue Box May create a subset of data rows (Select Variables) based on condition(s) satisfied Sample Excel Data File: qetools-sampledata.xlsx 15 1.2 Data Manipulation Subset Data – Sample Result Data are stored on datasheet in next open column to the right with new variable names (suffix added) . Subset to only include data for each row where Team = C 16 8 www.qetools.com QETools Tutorial - Part I 1.2 Data Manipulation Split Data by Group – Dialogue Box Split command creates data subsets of all selected rows of data Select Variables for each unique value of the Grouping Variable identified 17 1.2 Data Manipulation Split Data by Group – Sample Result Data are stored on datasheet in next open column to the right with new variable names (suffix added) The output is separate columns for each Output Variable . ‘TimeWaitingRoom’ . ‘WaitClinician1’ . WaitClinician2’) for each of the selected Grouping Variable . Team A . Team B . Team C 18 9 www.qetools.com QETools Tutorial - Part I 1.3 Six Sigma Methods – Tool Road Map QE Tools also provides a Six Sigma problem solving roadmap with common analysis steps and hyperlinks to analysis tools and templates 19 1.3 Six Sigma Methods – Tool Road Map Tool Roadmap: Define/Measure Phase Task Task Description and Tool Road Map (with Hyperlinks) DEFINE Define Problem Identify Problem, key customers, and assess impact in terms of $$ if possible – Tools: Project Charter SIPOC QFD - House of Quality Scorecard Analysis Pareto Chart Other Tools: Value Stream Map, Flow Chart, Swim Lane Diagram, Affinity Diagram, Cost-Benefit Analysis, Project Plan Identify Critical Y and assess its current state (e.g., Data Pattern, Process Stability, Process Capability/DPM/DPMO). MEASURE: Identify Key Output Note: select method based on Y data type (continuous/discrete, binary, or binary w/ multiple opportunities) Assess Current State Compute DPM, DPMO, Sigma Level, Yield (Unit-based, Rolled Throughput), or Process Capability Index (e.g., Pp, Ppk) Performance Process Capability Process Capability Process Capability Sigma Level and Graphical Summary Graphical Summary Graphical Summary Binary Tabulation DPM Converter (Normal) (Non-Normal) (Binary) FMEA Analysis Scorecard Analysis Yield Analyzer Assess stability of Y Plot Y versus time ( X-axis in time order) and assess if problem is chronic and/or sporadic. (time order) Assess if any trends in data over time (may include comparison to target performance levels or specification limits). Run Chart Blue Text representsAssess hyperlinksif process is in-statistical to controlvarious (process stability analysis). Select appropriate SPC chart based on the if Y is continuous variable data (or may be modeled as continuous)? analysis and templates in QEToolsIf subgroup size = 1 (or unknown), use: I / MR If subgroup size = 2 - 10, use: X-Bar / Range If subgroup size > 10, use X-Bar / S If Y relates to yield or % defective (each unit is defective or not)? If subgroup size is not constant, use: P-Chart If subgroup size is constant, use: P-Chart NP-Chart If Y relates to DPMO (1 or more defect opportunities per unit)? If subgroup size is NOT constant, use: U-Chart If subgroup size is constant, use: U-Chart C-Chart Describe Distribution of Perform distribution analysis. Select method based on Y-data type Y (non-time order) 20 If Y is categorical data (with multiple categories) --> use: Pareto Chart If Y is a set of proportions --> show distribution of sample proportions using: Histogram If Y is discrete/continuous --> show distribution using: Process Capability Process Capability Histogram Single Box Plot Graphical Summary Graphical Summary Dot Plot (Normal) (Non-Normal) Summarize Data and Assess if Mean and/or Compute descriptive statistics of Y and assess if mean and/or variation concern. 10 www.qetools.com Variation Concern Process Capability Process Capability Descriptive Graphical Summary Graphical Summary Statistics (Normal) (Non-Normal) Measurement Systems Assess quality of the measurement data for Y – verify if measurement system is effective (preferably quantitatively Analysis using measurement system analysis techniques) Paired (Repeated) Attribute Matching Gage R&R Study Measurements Study Study ANALYZE: Qualitative Analysis Identify possible key X’s (usually prior to Quantitative Analysis): Possible tools include: Cause-and Effect FMEA Other Tools: P-Diagram, Affinity Diagram Collect Data (check sheets, observational study of X's and Y's, controlled experiment). Quantitative Analysis: Analyze data to identify cause of the problem (key X's). Possible analysis tools include: Stratify Y by a grouping variable X (Stratification Analysis) Desc Statistics Mulitple Box Plot Scatter Plot Pareto Chart Multiple Tabulation (Grouping) Cross Tabulation Binary Tabulation Test for a Statistically Significant Difference Using Hypothesis Test. Select appropriate test on the following: Test variance effect on Y for X at 2 levels (variance Group A vs. Variance B): F-test Test mean effect on Y for X at 2 levels using paired data: Paired t-test Independent Test mean effect on Y for X at 2 levels: Samples t-test Test two proportions (Proportion Group A vs. Proportion Group B): Two proportion test Test mean effect on Y for X at 2 or more levels using independent samples: One-Factor ANOVA Test mean effect on Y for two X variables at 2 or more levels each: Two-Factor ANOVA Examine relationship between a single Y and X variable (prediction equation, Correlation, and R-squared): Scatter Plot Simple Regression Examine relationship between a single Y and mulitple X variables: Multiple Run Chart Multiple Regression Correlation Matrix Queuing Analysis Perform a Controlled Design of Experiment: Control Chart Create an Define Existing Analyze QETools DOE Analysis Experiment Experiment Experiment Other Tools: Multi-vari analysis, stepwise regression IMPROVE: Identify Improvement Identify improvement countermeasure (new procedure, change process setting, poke yoke, process monitoring Compare alternative solutions using tools from analyze phase or evaluate alternatives using: Pugh Matrix Assess the before/after effect of improvement recommendation relative to current state Process Capability Process Capability Process Capability Sigma Level Graphical Summary Graphical Summary Graphical Summary Binary Tabulation Calculator (Normal) (Non-Normal) (Binary) FMEA Analysis Scorecard Analysis Simulation Analysis Other Tools: Future State Map, Revised Process Flow Chart CONTROL: Create Control Plan Prepare a process control plan or document method of control.