Six Sigma Quality Resources for Software & Information Technology In association withSix Sigma Advantage, Inc. - Six Sigma Third Wave for Software Development
 Main Site > Software / IT Channel > Statistics  > Data / Sampling / Descriptive Statistics Search:
 
 for    
Publications
Marketplace
| iSixSigma
Stuff
| iSixSigma
Blogosphere
| Events
Calendar
| The
Dictionary
| Discussion
Forum
| Find
a Job
| Post
a Job
| Industry
News
| Newsletter
Signup
| Sigma
Calculator
| Online
Surveys
2008 Version! DMAIC Training Slides: 1,176 Slides + Instructor Notes and More for $99.95
iSixSigma Magazine Signup
 iSixSigma Live!  
  iSixSigma Live! Summit
  Agenda
  Registration Info
  Breakthrough Awards
 Free Newsletters!  
  Sign Up Now!
  Manage Subscriptions
  New To Six Sigma?
  Six Sigma Q&A
  Cert. Practice Test
  Problem Solving Wizard
  ISSSP Info
ISSSP Is The Official Six Sigma Society of iSixSigma
 Channels 
  iSixSigma Main
  Europe
  Financial Services
  Healthcare
  Military
 Quality Directory 
  Recent Articles
  Certifications/Awards
  Consultants
  Culture Evolution
  Methodologies
  News & Events
  Organizations
  Product/Service Guides
  Statistics & Analysis
   Normality
   Variation
  Tools & Templates
  Voice of the Customer
  Free Whitepapers
 Related Topics 
  Innovation
  Outsourcing/Offshoring
  Business Process Mgt
 Quick Access 
  Help
  Search
  Advertise Here
  Article Archives
  Newsletter Archives
 User Feedback 
  Please suggest site
  improvements.
 
  [ larger form ]

Actionable Information From Soft Data

Bookmark This Page Bookmark This Page
Email This Page Email This Page
Format for Printing Format for Printing
Cite This Article Cite This Article
Submit an Article Submit an Article
Six Sigma Article Archive Read More Articles
Related Tools & Articles
  • Six Sigma Quick Poll
    Does your company or department have appropriate metrics in place?
    Yes
    Not sure
    No
    Discussion Forum
    "I'm wondering if anyone has implemented Six Sigma metrics (effectiveness and efficiency) for the Accounts Receivable department at the operations level (billing accuracy, defects in billing statements, timeliness, cost, etc.). It's a key part of the project I'm working on in establishing new metrics."

    Accounts Receivable Metrics
    By G
    Download Products
    eorge H. Chynoweth, Ph.D.

    Engineers, Six Sigma practitioners, and other researchers often work with "hard" data - discrete data that can be counted and legitimately expressed as ratios. But what of "soft" data, things like opinions, attitudes, satisfaction? Can statistical process controls (SPC) be applied here? Can process variation in customer satisfaction, for example, be measured and then reported to management in a meaningful way? Can we leverage "appeal", "responsiveness", or "value for money spent"?

    In Visual Explanations, Edward Tufte demonstrates how the NASA Challenger disaster may have been avoided if the Morton Thiokol engineers had displayed their temperature vs. o-ring failure data in a meaningful way. They had all the data they needed - but it didn't get translated into information. In a similar fashion, a well designed survey or comment card will gather a wealth of data. The process of turning soft data into information (assuming the data are valid) is two-fold: knowing what to extract and knowing how to display.

    Information Extraction

    Visual Inspection & Intuitive Statistics
    Visual inspection of data is paramount to understanding it. Raw data, midpoints, ranges, and frequency distributions need to be examined visually before feeding it to a computer for advanced analyses. The need for complete familiarity with the distribution cannot be over stated. Two aspects of data that must be inspected are magnitude and consistency: How much and how many? Inspection will reveal outliers and provide relatively accurate estimations of the median, mean and standard deviation (this requires a bit of practice). The shape of the distribution will indicate if there is a problem with normality.

    Data consistency, often overlooked, should also be examined. Consider the situation of an experiment with six sub-comparisons, each one insignificant, but with all six differences pointing in the same direction. The researcher concludes no differences, but six consistent events yields a probability of .016, a rare event in its own right. No matter how good the statistical software, there is no substitute for human intervention at the right point. The foregoing is meant to help the researcher get a "feel" for the data, since a lack of understanding of the data will be easily transmitted to decision makers.

    Leverage
    Computer-calculated means and variances should be confirmatory at this point, assuming you have at least interval level data (data are rank-ordered, and have equal intervals between the numbers). We can now consider the item means (from a survey, for example) as performance indicators of small, individual processes. The means tell us how well each item is performing. But how do we know which processes are important and which are irrelevant?

    In a well constructed survey, there will always be one item which captures the overall meaning of the survey results: In an employee satisfaction survey, for example, it might be "I like my job" or "I like working here". All items on the survey should be pointing, somehow, to this bottom line. If we run correlations of each survey item with the bottom line, satisfaction in this example, we can see how well (or poorly) each item relates to satisfaction.

    This is leverage: the correlations reveal which items make a difference, and by how much, to overall satisfaction. We can see which items need to be "leveraged". By plotting a two by two table of Performance vs. Leverage (means vs. correlations), we can see where to focus first in order to 1) fix problems and 2) exploit what we do best. (See Table 1.) Caveat: Correlation does not mean causation, it only means a relationship exists. There may be an intervening variable that is responsible for causation. A root cause analysis, starting with the low performance, high leverage items, should be conducted, after examining process variation (see below).

     Table 1: Leverage Analysis
    Leverage Analysis

    Process Variation
    But what of the variation in these item processes? The Coefficient of Variation (Cv: the item mean divided by its standard deviation) provides an indicator of process variation for our soft data. It provides information regarding control and consistency. Some items, by their nature, will suggest where to start looking for root causes of problems, but not all. Looking at Performance vs. Process Variation may hold a clue for these items. Knowing that, in general, policies and procedures are static and consistent, and that people are dynamic and inconsistent, we can make an initial stab at where to focus on fixing some problems. Consistently low performance suggests a systemic problem, which in turn suggests that policies, procedures, methods, etc., may be a root cause. Any inconsistent (high Cv) performance suggests that people are influencing the variation: training, supervision/leadership, working conditions, etc., are some areas to consider for your fishbone diagram. By plotting the Cv vs. Performance (means) in a two by two table, the results identify consistently high performance items, consistently low performance items, etc. We now have performance and process variation data charted in a meaningful way (see Table 2). To see the relationship of the Cv to the frequency distribution graphically, see Table 3. This is very intuitive.

     Table 2: Process Analysis
    Process Analysis

    Actionable Information

    Making Data Understandable
    Displaying technically derived data (means, variances, correlations) to decision makers will require explanations that may overshadow and obscure the actual information to be conveyed. For example, explaining that there is a statistically significant difference between a mean of 5.84 and 5.43 on a 7-point survey scale will not promote your mission or your conclusions.

    Consider converting everything to percentages: this allows easy comparison across all items, as well as quick evaluation of each item. The numbers above convert to 83% and 78%, respectively. Everyone can quickly see and evaluate a difference of 5% with minimal explanation. The leverage data, currently in the form of correlations, should be converted to shared variance: square the correlation and multiply by 100. The display of an item with 60% leverage versus one with 30% makes technical explanations unnecessary - the boss can see which one is more important and by how much, and has a good understanding of why. Next, convert the Cv (standard deviation/mean) to a percentage by multiplying by 100. The only explanation required here is "lower is better" (six sigma standards will rarely apply to soft data). The beauty of these conversions is that the information contained in the data has not been lost or altered: information integrity remains intact, but now it's understandable at a glance.

    The (Almost) Holy Grail
    We now have information that is approaching action ability: performance, leverage, and process variation expressed in a recognizable format. If your survey has been well designed, you will also have collected some demographic data (it doesn't take much). Sort performance, leverage and variation by the demographic data - the derived information will change with each sort, specific to each demographic. We now have target groups.

    Using the two by two tables we can demonstrate, by target group, which items are important, in control, performing well, and should be exploited: this is what we do best, capitalize on it. We can also identify which items need to be fixed, and in order of priority. Some items, by their nature, will suggest where to start looking for root causes, but not all. The Performance vs. Process Variation Table may hold a clue for these items. Knowing that, in general, policies and procedures are static and consistent and that people are dynamic and inconsistent, we can make an initial stab at where to focus on fixing some problems. Consistently low performance suggests a systemic problem, which in turn suggests that policies, procedures, methods, etc., may be a root cause. Any inconsistent (high Cv) performance suggests that people are influencing the variation: training, supervision/leadership, working conditions, etc., are some areas to consider for your fishbone diagram.

    Your committee, boss, and CEO now have rich information regarding what to exploit, what to fix, and where to look. A question that often arises at this point is, "Anyone have any ideas on how to do this?" If the survey was well designed, it solicited comments in such a way that it greatly increased the chances of garnering actionable ideas: "Give us ONE good idea on how we can improve xxxx." This is a simple and focused task, rather than a vague request, and tends to elicit actionable responses. Review all comments (data inspection). Review them again, this time looking for themes. Group the comments by theme. Your customers, employees, constituents, etc., can generate a smorgasbord of ideas. Enjoy the buffet.

    Once you have a feel for your data, you can run these (relatively) simple analyses and comparisons and display clear and powerful information that provide road maps for action.

     Table 3: Getting A Feel For Data
    Getting A Feel For Data

    About The Author
    George Chynoweth is the owner of dxResearch, a consulting firm specializing in the Design of Experiments and actionable information. George has 26 years experience with the Federal Government in both program evaluation and management. His last assignment was with the Quality Management Office for the Office of the Secretary of Defense where he designed and developed the Interactive Customer Evaluation (ICE) prototype, an online comment card and customer complaint management application which is now in use throughout the Dept. of Defense. George also taught Research Methodology and Psychological Testing at Boston University's Graduate School, and management classes at Central Texas College.

    George holds a Ph.D. in Experimental Design with a cognate in Community Psychology. He earned an M.Ed. in Social Psychology, a B.A. in Biology, and has advanced training in multivariate statistics, database design, and computer science applications.

     
    Rate This Article:  Current Rating: 4.11
      Poor    Excellent     
              1    2    3     4    5
    Copyright © 2000-2008 iSixSigma – All Rights Reserved
    Reproduction Without Permission Is Strictly Prohibited – Copyright Requests


    Publish an Article: Do you have a Six Sigma tip, learning or case study?
    Share it with the largest community of Six Sigma professionals, and be recognized by your peers.
    It's a great way to promote your expertise and/or build your resume. Read more about submitting an article.

    BEST SELLING PRODUCTS (iSixSigma Publications)
    1. Certified Lean Six Sigma Green Belt Assessment Exam
      This assessment exam is useful for students interested in assessing their knowledge of Lean Six Sigma on the Green Belt ...
    2. Six Sigma Black Belt (DMAIC) Training Slides
      The 2008 Six Sigma Black Belt course is comprised of: 1,176 PowerPoint slides, Instructor notes, Slide explanations, 37 ...
    3. Six Sigma DMAIC Training Slides
      The complete 2008 Lean Six Sigma DMAIC course prepares participants to perform the role of a LSS Black Belt; covering wh...
    4. Process Management Training Slides
      The 2008 Process Management course is designed in two phases comprised of:352 Powerpoint slidesInstructor notesSlide exp...
    5. Six Sigma Green Belt Training Slides
      The 2008 Six Sigma Green Belt course is comprised of: 1047 slidesInstructor notesSlide explanations35 data sets20 suppo...
    6. Certified Lean Six Sigma Black Belt Assessment Exam
      Interested in assessing your knowledge of Lean Six Sigma? Preparing for certifications? Testing your students and traine...
    7. 5S Training Course
      One of the key fundamental tools of process improvement is 5S. 5S is a methodology for organizing and minimizing item...
     
    Six Sigma AdLinks
    Improve IT Projects With Six Sigma. Villanova University.
    iSixSigma Live! Save up to $700
    iSixSigma Job Shop: Find The Key Person
    Lean Office, Lean IT/IS. Act Now and Save.



    Google AdWords
     
    Home | Discussion Forum | Event Calendar | Job Shop
    Link To iSixSigma | Rate This Page | Report A Problem | Free Content For Your Site | Submit Article For Publishing
     Terms of Service. ©2000-2008 iSixSigma. All rights reserved. v3.0lb, 2.0-A-244
    About iSixSigma · Contact Us · Privacy Policy · Site Map
    nogeo