iSixSigma

Strayer

Forum Replies Created

Viewing 100 posts - 1 through 100 (of 460 total)
  • Author
    Posts
  • #244496

    Strayer
    Participant

    I might suggest that you do some root cause analysis to discover the KPI.  From what you say it appears that the harvesting process is the source of waste and the root cause lies somewhere there.  Assuming that the harvesting process is the same in all hectares/acres, the variance in yield/waste per plot is probably noise.  You’re being led down the garden path if your KPI is noise.  You’ll put a of effort into collecting and analyzing meaningless data.  If you’re looking at the harvesting process you may not need to randomly sample various plots.  You may only need to look at one test plot.  I’d advise to do a fishbone (Ishikawa diagram), maybe some additional RCA tools, and do some research on harvest waste for this and similar crops.  Convince yourself that harvesting process is the source of waste but don’t assume it is.   Find the KPI.  If you can do that, you should be able to sell it to management and avoid a lot of wasted effort.

    0
    #244445

    Strayer
    Participant

    I was going to let y0ur complicated question go for those contributors who are much more knowledgeable about statistics and sample size.  But on second thought, maybe you’re overcomplicating the matter.  Why not measure the waste on a hectare, or even just an acre?  Do RCA to identify the root cause of waste.  Improve.  Remeasure.  If that reduced waste, standardize the improvement.  Repeat, using a different hectare or acre the next time.  Granted with an annual production cycle it may take years to significantly reduce waste.  But that will also be the case if you employ more complicated statistics.  Consider that the difference between waste vs. production on one hectare/acre vs. another probably has more to do with harvesting process than any other variable, and harvesting process is probably the same.

    1
    #244348

    Strayer
    Participant

    FYI, ASQ’s GB certification is lifetime.  We recognize that a GB is not a full-time six sigma professional but has sufficient knowledge and experience to serve on teams.  I think that should apply to internally certified GB’s.  What bugs me is BB’s who earn certification, internally or externally, for advancement rather than what they do on the job.  If they want to continue to be recognized as BB’s they should be periodically recertified using the same criteria as for original certification.

    0
    #244322

    Strayer
    Participant

    It depends on the certifying organization.  ASQ, for instance, requires that you do certain things, and submit proof, to maintain your certs.  Otherwise you’ll have to go through the certification process all over again.  I’ve seen situations where people on the management track go through BB internal training and certification, and never really use it again.  Recertification would be appropriate in those cases if they want to continue to call themselves black belts.

    0
    #244274

    Strayer
    Participant

    I think this is a poor choice for a six sigma training project.   I suppose that your instructor has his/her reasons, maybe that this is something management wants to address, so you’ll have to live with it.  If, as you say, your teacher isn’t really knowledgeable about forecasting methods, that’s a real bummer.  I’d advise you to look up information on Six Sigma for Demand Forecasting.  There’s some pretty good stuff there that you might find helpful.

    0
    #243708

    Strayer
    Participant

    It sounds like you posed a challenge to improve something that was outside their area of responsibility and no one, understandably, wanted to become responsible.  As customers/users of the bathrooms you can identify defects and report them to those responsible but you don’t control their processes so you can’t improve them.  A training exercise should use a scenario where participants can identify with the process to be improved.

    1
    #243577

    Strayer
    Participant

    You shouldn’t skip MSA.  Per my previous comments, you need to use the appropriate tool/method rather than force-fit a tool such as GR&R.  Also beware that there may be hidden (uncaptured) data when you’re dealing with something like delivery time.  I recall a case where the data showed that delivery times were nearly always met and measurement of days to delivery was accurate, according to MSA.  But customers complained.  It turned out that customer service did not enter orders until they could confirm with production since the system made it a real pain to change production schedules and/or orders and keep them in synch.  So this, and negotiating with the customer, was all done off-line with no record!

    0
    #243533

    Strayer
    Participant

    @FabioCacciotti  MSA should always be part of the process.  We need to know about confidence in our measurements and evaluate how much of the variation we’re seeing may be due to our measurement system.  Reputable polls, for instance, state a margin of error based on sample size relative to population and, if they’re sophisticated enough, considering randomness of the sample.  The problem many beginners have with MSA is that the tools they’ve been taught may not be applicable to the measurement system they’re using.  For instance, you wouldn’t use GR&R unless your measurements come from a calibratable instrument such as a clock.

    0
    #243510

    Strayer
    Participant

    @Erik2018  The 1.5 shift is controversial.  You’ll find much discussion here and elsewhere about it, including whether or not 1.5 is the right value to account for long term drift.  Most of us just accept it.

    1
    #243509

    Strayer
    Participant

    You are using attribute data (yes/no) rather than proportional data where there is a range of values for the variable.  Look up MSA for attribute data and assessing reliability of qualitative measurement.  In your case I’d be more concerned about sample size and sample selection, unless there’s a question about accurately measuring days to delivery.

    0
    #243414

    Strayer
    Participant

    Reading between the lines, I’m guessing that you might be troubled by the fact that there doesn’t appear to be a repeatable process, where defined inputs go through defined steps to produce defined outputs.  I had to deal with the same issue in software development.  Everything seems to be a one-off that will never be done again.  But that doesn’t mean there isn’t a process.  To elaborate on @cseider comment, you might look at multiple project records to identify frequently occurring problems/losses.   That’s something you can attack.

    1
    #243355

    Strayer
    Participant

    As a senior ASQ member who knows people involved in creating the exam questions, I can assure you that none of the practice questions available from ASQ and other sources will appear on the exam, as such.  The practice tests are to help you decide whether or not you’re prepared to sit for the exam.  It might be useful if these questions referenced the BoK, but not that much.  Either you know the BoK or you don’t.

    You don’t have to use these practice questions unless you want to.  Look up qualifications to sit for the exam on the ASQ website.

    0
    #243199

    Strayer
    Participant

    My “go-to” tool when time is the concern is a Time Value Map.  It shows how much time is spent on each step, which are value-added and non-value-added, and wait time between steps.  You want to minimize the non-value-added and wait before trying to speed up the value-added.  There are three caveats about using a TVM.  It assumes a stable  process.  It assumes a linear process.  You have to measure time for each step often enough to be confident about the average (see sample size), and if there’s wide variance in any step that’s another problem.

    0
    #243126

    Strayer
    Participant

    My only experience with the insurance industry is as a customer.  From that perspective I’d say I’m dissatisfied.   It’s  difficult to understand the coverage and terms, premiums are expensive, you often have to fight when you have a claim, and what you get is often less than you expected.  You might start with voice of the customer, what they perceive as defects, and the business benefit of reducing those defects, not just efficiency for processing claims and reducing overhead expense.  To be successful your training program should focus more on the customer than on internals.  That’s true for any LSS initiative but it’s easy to overlook in service industries where there is no physical product, and arguably where it’s even more important.

    0
    #243123

    Strayer
    Participant

    @anthony2019  I hope you didn’t think I was trying to discourage you with my previous post.  I’ve known people who successfully used internal company projects as dissertation topics.  Just wanted to give you a reality check.  The sustainability issue is a big one.  More than a few companies did things such as requiring everyone in certain positions to earn green belt, and a certain number of black belts per department, the latter open only to those on the management track.  Most people never did another improvement project.  You can find research about this.  p.s. I think the idea of continuous improvement projects is basically a mistake.  It should be a mind set.  Sometimes it may be a project.  More often it should be using the tools to tweak the process whenever you recognize something amiss.  Doing projects to earn required belts led people to think they’d gotten the belt and now they’re done with it, because doing such projects wasn’t part of their regular job.

    0
    #243078

    Strayer
    Participant

    Assuming that your dissertation is for a graduate degree, you probably understand that they’re looking for an original contribution to the body of knowledge, not just doing research and regurgitating facts.  Researching sustainability for a single SME group might take years in order to draw any conclusions, and the general applicability of those conclusions will be questioned so you’d better be able to back it up with wider research.  If you’re going to focus on the group where you work, you have a good historical starting point.  But consider that your employer has a stake in what you disclose.  You probably signed some sort of agreement when you were employed.  Expect them to want to approve your research project, limit the amount of time you and other employees spend on it, and review and approve your dissertation before you present it.

    0
    #242489

    Strayer
    Participant

    @sheilalopez  The Shainin System (tools, methods, and training) is proprietary.  While much information about it is in the public domain you’ll have to pay for the details, and it isn’t cheap.  Here’s a link that may be helpful. https://www.researchgate.net/publication/233362346_An_Overview_of_the_Shainin_System_for_Quality_Improvement

     

    0
    #242378

    Strayer
    Participant

    Well, yes.  Since the red x is the variable which has the greatest influence on the desired outcome.  The problem, and I have a lot of experience in this space, is that the “y” is often fuzzy and not easily measurable.  It’s often biased by what some manager wants without regard to voice of the customer, quality, or financial results.  If you can’t measure the “y” good luck determining the red x.

    0
    #241845

    Strayer
    Participant

    @KayKL When I did it I expected to rely on my reputation and contacts as a starting point.  But I had non-compete and non-disclosure agreements as you probably do.  So I had to build a new network.  I found a great small business lawyer who for a surprisingly small retainer fee helped me to create a business entity, comply with regulations, tax, and such.  This lawyer organized his clients as a networking community – monthly client meetings where we met, learned from, and helped each other.  That, along with getting more involved with professional organizations and local business networking communities, establishing a website, making myself known in on-line social networks such as LinkedIn…

    Bottom line is that you’ll have to work hard to market what you have to offer and find clients.  You’re going to become a self-promoting salesperson.  You can expect to spend money rather than earning it for quite some time.  If you aren’t prepared to do all of these things,  don’t do it.

    0
    #241844

    Strayer
    Participant

    @aayanbule @Mike-Carnell  I was a bit remiss in my initial comment.  While CMMI appraisal and QA performed according the Capability Maturity Model are very audit-like they are also very different.  The goal is process improvement rather than strict compliance with policies, procedures, and standards.  As an appraiser, if we find that an organization has an alternate practice that achieves the goals, that may be a good thing.  We might even champion revising the model.  For instance, CMMI was extensively modified to include agile methods, which many IT organizations were using with great success.  If we’d done strict auditing we would have dinged them for not following the rules and let it go at that.

    The purpose of QA, as defined in CMMI, is to provide objective insight into how well the organization’s standards are working and the quality of the resulting products.  Yeah, we note deviations and non-compliance issues in our findings and we track them to closure, but we’re just as interested in understanding why these occur, and whether or not what they’re doing is better in some way.  Unlike the typical audit where closure is either corrective action or management signing off that they accept the risk, it may be a decision to revise the policies, procedures, and standards.

    So the transition was just the next step for me.  It may be a lot more difficult for someone who’s only been a strict auditor, focused on reporting non-compliance and the risks that entails.

    0
    #241631

    Strayer
    Participant

    @Mike-Carnell Belly laugh.  Auditors do serve a useful function.  But strict auditing tends to suppress innovation – Stop doing that!  You aren’t following the rules.  Fortunately in my audit-like positions it wasn’t strict audit.  CMMI and QA (as defined in CMMI)  places value on recognizing innovation and evaluating whether or not it might become part of the standard process, or an option.

    2
    #241316

    Strayer
    Participant

    Audit can be a good starting point.  You do evidentiary studies to find what isn’t being done the way it’s supposed to be done.  That’s a large part of what we do in continuous improvement and it’s a skill that some people find difficult.  My path from project manager to LSS consultant included IT quality assurance and CMMI appraiser, both of which are essentially auditing.  Since you’ve been auditing for quite some time you’ve probably learned to point out that it’s a process failure, and not to blame individuals.  Assigning blame is a sure way to make yourself unwelcome, whether you’re an auditor or a continuous improvement leader.  So you’ve got that going for you.

    You don’t have to have six sigma or any other certification to succeed in continuous improvement.  Some people just do it and develop a reputation with management and colleagues.  Of course that would conflict with audit  so you probably can’t go there in your current job.  To make the career change you’re going to need certification to impress HR and hiring managers.  Six sigma belts aren’t the only continuous improvement certifications so you might want to research related certifications.

    There’s probably an American Society for Quality section in your geographic area that meets regularly.  You might get in touch with them.  You can find out about local sections from their website.  As a long-time senior member I can tell you that ASQ is great for networking, advice, training, and certification.  My section welcomes  non-members at our meetings.

    1
    #240844

    Strayer
    Participant

    Per @rbutler we don’t want to the clutter the graph and risk obfuscation.  I’ve seen spec limits added for a presentation when someone wanted to show that the process was statistically under control, but out of spec.  I think that was a good use.  But what if it was out of control but within spec?  Should we disregard what the control chart is telling us?

    1
    #240770

    Strayer
    Participant

    If you don’t know the standard sample size calculation formulas, look them up on this site and elsewhere.  You can also find on-line sample size calculators.  Not trying to be snarky.  It’s just that you said your best “estimate” is 638 pieces and that doesn’t sound like you’ve done the math.  If you have and you still have questions about optimum sample size, describe your concerns and one of us may be able to give advice.

    0
    #240642

    Strayer
    Participant

    @Mike-Carnell  A good CEO relies on experts.  And has the wisdom and vision to champion.  To get back to the original post, as an intern you are not a recognized expert.  You will not overcome resistance.  The best you can do is to tackle a quick and inexpensive improvement and build on your success, here or elsewhere.

    0
    #240587

    Strayer
    Participant

    I concur with comments about CEO.  When I was with AlliedSignal Larry Bossidy bought in to SS big time, to the point of saying that everything we do is SS.  We made progress, although there was valid criticism that it couldn’t always be seen on the bottom line.  Then we bought/merged with Honeywell.  The new CEO wasn’t a disciple, we fell back, were nearly bought by GE, and when that deal fell through Bossidy was brought back to get us back on track.  He did.

    But to get back to the original question.  People tend to resist change unless things are really bad.  It’s hard to get line people to buy in unless you can prove that it’s in their best interest, or management says “do it”.  Management won’t say that unless it comes from the top down.  And execs won’t do that unless they’re true believers or you can give clear evidence that your improvement plans work — data and results, not opinions, not references to the literature, case studies, results in other companies, etc.  If you don’t have executive support from the start, start small.  Get a line manager to let you try.  Find a problem that you can improve without a major investment in time or money.  Show results and work upwards.  As an intern you probably won’t get beyond the first project, or maybe not even complete it, but you may be able to get a foot in the door to changing the culture.  And that’s good for all.

    0
    #240282

    Strayer
    Participant

    What was the question? What did you answer? What don’t you understand about the “correct” answer in the practice exam? We’re glad to help. I would caution you, however, to check the copyright notice for your practice exam. You might need to pose a general question rather than posting a copy of the published question and answer.

    0
    #240244

    Strayer
    Participant

    I wouldn’t call this a benchmark but I was involved in a study at our IT dept. at AlliedSignal after hearing that non-production-line employees typically only spend about 2/3 of their time doing productive work. Thanks to administrative tasks, meetings of questionable value, socializing, etc. We found it to be true. We also found that doing the study interfered. One off-shoot was a boss who’d come through the office saying he wanted to see heads down and fingers flying on the keyboards, as if that meant productivity. In many fields people are often more productive if they have thought-time. We might look like we’re wasting time. I often benefited from getting away from the desk, take a walk, chat with someone. Then I’d have an “Aha!” moment. The problem with employee utilization measurement is that except on the production line where people are essentially machines you can’t measure what matters except by results. So I stand by my initial comment. You say your client is concerned about over utilization due to manual processes and about work distribution. Apply lean thinking to identify and eliminate non-value-added tasks rather than waste time on an essentially useless metric.

    0
    #240218

    Strayer
    Participant

    I encourage you to stop wasting time measuring it, since rigorous time-keeping is also wasteful. Instead look at what people do, ask whether or not it’s productive, and if it isn’t, whether or not it’s productive or necessary. Change the culture so that everyone considers this.

    0
    #239664

    Strayer
    Participant

    Many of us end up somewhere we hadn’t thought of going. For me it was a winding path.
    – science/math major in jr. high where I learned FORTRAN (mid 1960’s)
    – English major in high school, interested in becoming a teacher
    – Secondary education major in college (quickly realized I didn’t want to go there)
    – Liberal arts degree with double major in English and philosophy
    – Various low-pay jobs
    – temporary job as teletype operator led to an offer to manage the wire room and automate it, and take night classes at company expense to learn what I needed to know
    – Coordinator data communications and data input control
    – senior programmer/analyst and systems manager (after automating the wire room)
    – IT project manager
    – TQM facilitator for IT and internal CMM/CMMI appraiser
    – IT six sigma trainer, although not a black belt. Employer only gave that to people on management track
    – Global IT quality assurance leader
    – Independent consultant
    – Retired

    1
    #239609

    Strayer
    Participant

    There are so many. But my first step if the problem hasn’t been narrowly defined is “is / is not” analysis, often attributed to Kepner-Tregoe but hard to call original. Just write down what you know to be true about the problem and what you know to be untrue. No assumptions here. Just what you know for sure at present. Try to cover everything you can think of that’s relevant. Take a good look at these two lists. It’ll lead to more questions and eventually to the most appropriate tool.

    2
    #239577

    Strayer
    Participant

    @Sharmin If your project is “boiling the ocean” (Making huge changes without resources or commitment to do it) it’s destined to failure and whatever you do to address the symptomatic signs of impending doom will not avert this. When “work or some other emergency” gets in the way of team members doing what you need from them you can be sure that they aren’t committed, and you might assume that they see impending failure and would rather not be associated with it. If this is what’s happening I’d advise you to meet with your VP of quality and the process owner to have an honest and open discussion. Ideally you’ll want someone who is above both of them and an independent expert on the project space to participate. If you can do this you may end up with a reduced and more achievable scope, and the commitment to do it. I’m making assumptions from what you said but I’m also speaking from experience where projects failed or were revived and successful with reduced scope.

    0
    #239467

    Strayer
    Participant

    To elaborate on @Mike-Carnell comment, in the transactional space specification limits are typically set by service level agreements, which are negotiated as compromise between what the customer (external or internal) might accept, and estimated cost to provide. This results in dissatisfied customers while contractors (or internal operations) claim that they’re doing really well and have data to prove it, while customers (external or internal) are dissatisfied. This is not acceptable. Dissatisfaction encourages management to outsource, or find a new contractor, resulting in a new service contract, and the cycle takes another round. I think the bottom line in the transactional space is that good enough to meet specifications is never good enough. Ultimately customers want instant and cost-free transactions. Anything less is an arbitrary compromise. So our goal in this space is continuous improvement and never being satisfied.

    0
    #239465

    Strayer
    Participant

    @Aerospacer I’m sure you know that when the result of a reputable opinion survey is published they include a margin of error. This is MSA although it isn’t called that and isn’t calculated using GR&R. Bottom line is that we’ve long known that measurements are not 100% accurate and reliable and those who are wise have found ways to put a number on this so that we know how much we can trust our measurements, long before six sigma.

    1
    #239430

    Strayer
    Participant

    I don’t know the answer. As soon as people began measuring it was known that there had to be standards and that measurement instruments weren’t infallible. Many people have contributed to the body of knowledge for statistically determining how much of the observed variation may be due to the measurement instrument, from Shewhart in the 1920’s and others before him. Tracking down the origins would be an interesting topic for a research paper but not germane. For understanding why and how we do MSA you probably can’t do better than Wheeler.

    1
    #239401

    Strayer
    Participant

    It sounds like you are conflating specification limits and control limits. Specification limits are set by the customer. They are not calculated. Control limits are calculated from the measured variation within the process. We want control limits to be within specification limits but they are otherwise unrelated.

    0
    #239400

    Strayer
    Participant

    One of my major complaints is when people say that you must use a particular tool because it’s part of the process. GR&R is about determining how much of the variation you’re seeing is due to inherent variation in a physical measurement instrument. There are better tools for MSA when you don’t have a physical measurement instrument, and force-fitting GR&R is likely to mislead.

    0
    #239399

    Strayer
    Participant

    Have you looked at Wikipedia? The page on measurement system analysis has references. Just saying.

    0
    #239128

    Strayer
    Participant

    Keep in mind that many companies, at least in the United States, are most interested in hitting the numbers for the next financial report. I’d look for a “quick hit”. Something that should be relatively simple and inexpensive to improve. Do that and document bottom-line proof. Nothing sells like success.

    0
    #238813

    Strayer
    Participant

    There’s been much discussion about this “fudge factor” in this forum and elsewhere, including differentiation between short-term and long-term sigma, process drift, and so on. Crosby insisted that zero defects is the goal. Otherwise we’re saying that our goal is to produce a certain percentage of defectives, which makes no sense. Problem is we can never prove we’ve achieved zero defects long-term. There’s always a chance that a defect will appear. So 6 sigma is a practical goal, if not the ultimate. Most of us have stopped worrying about the shift. As you said, it was included in the formula for practical reasons.

    1
    #238746

    Strayer
    Participant

    The biggest challenge is changing company culture. Even in many companies that went big-time with LSS we often had to wonder whether or not they really got it. For example, requiring us to commit to improvement goals and deadlines before Measurement, because we had to sell the project before we could get approval to even begin understanding the problem.

    4
    #238589

    Strayer
    Participant

    I agree that for best results the FMEA team comes with data and aren’t just guessing or advocating based on prejudices. But I stand behind my previous comment that it’s about arriving at consensus. Each subject matter expert brings something to the table. If you do a rigorous FMEA following the AIAG manual, FMEA is a project, not an exercise. The results of the exercise approach, often done in just one day, can be very useful. But we should remember that the RPNs don’t mean that much unless there are very wide separations.

    1
    #238573

    Strayer
    Participant

    An FMEA is a team exercise to identify and arrive at consensus on RPN factors. The result is probability based on the knowledge of participating experts. If you have the right people on your team, subjectivity shouldn’t be a big issue. Things tend to balance out. There are better tools, such as fault trees, for objective analysis but they aren’t good for prioritization, which is the reason we do an FMEA. In my experience an attempt to get all the data and do objective analysis turns FMEA into a project in itself, and the results are not better.

    1
    #238572

    Strayer
    Participant

    Key difference is that a project begins and ends. A process continues after your project. When you do a SIPOC or other method to set the scope boundaries for your project you are defining what part of ongoing operations is in scope for your project. Your are saying that your project deals with the process that’s within these boundaries. But your project scope is your goals, your resource requirements, your team, your schedule, in short your project plan.

    1
    #238567

    Strayer
    Participant

    In the nineties there was a Phd. in our organization who was implementing expert systems to capture the knowledge of key employees and help with future decision-making. It ended up not going very far, partly because the technology was just beginning. But he did manage to get cooperation. One thing he stressed was that we aren’t trying to replace you with a machine, or with some lower-salary employee. We want to help you do even better.

    0
    #238486

    Strayer
    Participant

    Off the top of my head, I’d guess that your organization is relying more on individual expertise than on defined process. If that’s the case, you want to reverse it by defining and standardizing processes. Getting those who don’t screw up to reveal how they’re more successful can be difficult. They might consider that their secret to job security. You can’t accept that.

    1
    #237986

    Strayer
    Participant

    Sometimes benefits are called “soft”, such as making an internal report more useful, because we aren’t willing to do the work to determine how they affect the bottom line, although they do. That said, there are things such as goodwill, social responsibility, employee satisfaction and morale, that are good to do but have nebulous bottom line benefit. That doesn’t mean we shouldn’t do them. But they are not candidates for DMAIC projects.

    0
    #237984

    Strayer
    Participant

    You might find some help at the Project Management Institute’s website. Microsoft Project and other good PM software might help, even if you are dealing with on-going teams rather than projects which begin and end. Bottom line is that there are complex estimating formulas which are still “guesstimates”. You don’t know what you don’t know so you have to make assumptions, and people are not equivalent.

    0
    #237588

    Strayer
    Participant

    It’s often noted that software is different. You aren’t repetitively making things that conform to the same specifications. Every product is new. I’m glad to hear that your company uses agile and Kanban, which were developed to incorporate lean and reduce waste for one-off products. I’ve found that process maps, even value stream maps, aren’t very useful for agile software development. The only thing common between projects is the high level process. The reaction from teams is, “Well, duh. We get that. But we still have to discover what we need to do as we go along.”

    90% delivery with huge delays is far from typical for agile software teams. This suggests a lack of training and expertise, especially for team coaches (project managers). The transition from traditional project management to agile is not easy since you have to cast aside so much, such as detailed work breakdown structures, PERT estimating, detailed requirements, and so on. You might want to tactfully look into how well your organization is prepared to do agile before you try to analyze what’s wrong with the process and force-fit an improvement.

    0
    #237587

    Strayer
    Participant

    I’ve seen companies use sigma score to evaluate performance of departments and projects. Sure, you can put a number on it. It’s just math. But it’s missing the point. What we care about is the quality we deliver to our customers. Some companies, GE for one, got so hung up on internal competition that they lost sight of that. Have you checked GE stock prices lately?

    0
    #237162

    Strayer
    Participant

    SIPOC is about external inputs to and outputs from the process, not about what happens within. Sure, there are suppliers and customers for each step within the process but don’t muddy the waters. What you want to do is set the boundaries for the process of interest, however broad or narrow. What crosses that boundary is what you put in the SIPOC.

    1
    #237161

    Strayer
    Participant

    Have you looked into Theory of Constraints? It may provide some insight into balancing the process.

    0
    #237104

    Strayer
    Participant

    Have you searched this site? There’s much discussion about use of six sigma in call centers that might suggest a research topic. You have to accept that your MBA must use publicly available data and nothing from your own company without explicit approval.

    0
    #236712

    Strayer
    Participant

    Are you asking what proportion of diners need to respond before it’s a reasonable sample size? It’s probably the wrong question. Most people won’t do it unless they’re very pleased, or displeased, or offered a bribe such as a discount. Feedback cards (as opposed to scientific surveys) are useful for seeing trends but not for much else. As @rbutler suggested, written comments are likely to be the most valuable feedback, as opposed to waitstaff asking “did you enjoy meal?” which is almost certainly useless. If you can encourage people to write a brief comment about their dining experience, and take the time to read and make sense of these, you should get useful insight.

    0
    #236606

    Strayer
    Participant

    I’m not quite sure what you’re asking since sigma level is derived from DPMO while OEE includes other productivity factors including equipment availability and speed. Can you clarify?

    0
    #236405

    Strayer
    Participant

    Here’s a simple thought. It’s an interesting statistics question but useless. Employers don’t care as long you arrive on time and would only have a policy for a 40 minute commute time if that was mandated by government regulation or union contract, which is highly unlikely. Employees do care, but how many of them would do the math or care about such fine distinctions? We don’t waste our time on useless questions and whoever asked you to answer this one is clueless.

    1
    #236277

    Strayer
    Participant

    Beware of building it yourself. It’s likely to incur much more expense than you want to invest and much more time than you’re willing to wait for. This results in projects that are abandoned before fruition more often than IT people like to admit.

    0
    #236156

    Strayer
    Participant

    A sample size of one can be sufficient in some circumstances. That’s the way water and food products are tested for bacteria and other contaminants. My father outlaw worked in the metallurgy lab in a steel mill and he’d get one sample from the furnace. If it wasn’t up to spec he’d tell them what they needed to add and then he’d get another sample. Over time you can do statistical analysis for additional insight but it would be wasteful to take multiple samples from the same homogeneous batch. But there’s a caveat (isn’t there always?) How much variation (R&R) is in your gauges and methods? If this variation exceeds your desired confidence level you might need multiple samples even if you reasonably expect them to be the same.

    1
    #236093

    Strayer
    Participant

    It sounds like you have the traits to do this. Some people don’t like to get down into the weeds, dig up, and analyze data. You are right that you need a basic understanding of statistics. But as @Mike-Carnell said, today we use software more often than knowing the formulas and doing the math. I’d suggest that you get in touch with the local section of American Society for Quality. ASQ’s GB certification is respected and does not have to be renewed once you pass the exam. Your local section may have a GB certification training program, as mine does. Whether or not you sit for the exam you’ll learn what you need to know as a solid starting point.

    2
    #236011

    Strayer
    Participant

    While there’s no single certifying body for belts some, such as American Society for Quality, carry a lot more weight. Certifications and degrees tend to just get you through the door since it’s mainly HR that cares about them and you might never see a hiring manager if you don’t get through initial screening, unless you make some contacts within the company where you want to apply who can short-circuit that. When I was a hiring manager I wanted to talk to people who’d been personally recommended more than candidates from a stack of HR-screened resumes. It’s a fact that networking will get you an interview before credentials will. Credentials matter. But you’re competing with a lot of others.

    In your resume and interview, talk about problems you solved and how that benefitted the bottom line rather than credentials and awards. You can do that with only academic experience. Why did what you did matter? How did it improve your academic organization? Don’t forget that an academic organization is still a business.

    1
    #235849

    Strayer
    Participant

    Regarding your second question, I wouldn’t use the GR&R results in calculating CPK unless it shows consistent skew. For instance, if you find that your gage tends to read high or low you might adjust for that. Otherwise GR&R only tells you about confidence in your measurement accuracy and only says something about confidence in your CPK.

    1
    #235555

    Strayer
    Participant

    You can find a lot of information on calculating sample size by searching this site. You can also find sample size calculators on the net if you’d rather not do the math. You need to know your population size (total units produced in a given period), standard deviation for the population (often estimated since measuring the entire population may be cost prohibitive), and your desired level of confidence (typically 95%). Are your measurements variables (potentially infinite variation depending how many decimal places) or proportional (discrete) where there is a fixed number of values such as A,B,C…? There are different formulas depending on that but some argue that you only need the standard formula. Regarding how often you should sample, this depends on cost/benefit and stability of your process.

    For research you might want to start with this Wikipedia article https://en.wikipedia.org/wiki/Sample_size_determination

    I’d advise you to just start doing it with whatever sample size is practical rather than trying to determine your optimum sample size at first. Management will often accept this because it’s a good thing to do, if it doesn’t cost too much. You’ll soon learn whether your samples are too large or too small. Just beware that you can only speak about defects found in the sample until you have a statistical basis for sampling.

    0
    #211448

    Strayer
    Participant

    We use VSM to redesign the process, to identify and to eliminate or minimize NVA operations in an improved process. You aren’t ready to go there and you’re trying to boil the ocean from what you said in your original question and last comment. Instead I advise you to simply map the process with a step-by-step flowchart, which may already exist, identify significant NVA (wastes) which the people who do the work probably know if you ask them, and choose one for a DMAIC project.

    2
    #210218

    Strayer
    Participant

    At AlliedSignal in the 90’s we used documented cost savings from six sigma projects, which had to be signed off by finance to confirm that the savings were real. Even so there were lots of questions about how real they actually were. We, GE, and others were criticized for not being able to show these claimed savings in our financial statements.

    Yes, you can use COPQ to evaluate non-transactional teams/processes. But it’s difficult. What are your baselines? How do you measure quality of what these teams do and the cost of it not being done well? As noted above, we used financial benefit of the projects compared to their cost. It seemed like a no-brainer but wasn’t very satisfactory.

    You’ll need a defined process for DMAIC and some repeatability for executing it in order to have comparable metrics. You might not want to go there since it places constraints on your teams and might prevent them from doing what’s best to achieve their improvement goals. The simplest thing is to measure how well teams improve the defined problems, according to their metrics. But that might not be enough to convince management that you’re getting results.

    0
    #210217

    Strayer
    Participant

    The triangle applies to project management. As you know, it’s said it can be good, fast, or cheap. Pick two. The third will be worse. It doesn’t necessarily apply to process improvement. If you improve quality you’ll likely improve efficiency and reduce cost as well. As for choosing a primary metric, the above gave good advice. Clearly define the problem and the measurement that shows that the problem exists. Most likely that will be your primary metric.

    1
    #209968

    Strayer
    Participant

    You hit the nail on the head, Mike. I would note that so often we have complaints about quality from outsourced providers but they say they’re satisfying the service level agreement. And it may be true. SLA’s are usually negotiated by purchasing and executives without involving quality professionals, so we tend to get averaged/massaged data and have no insight into what’s really happening. CMMI (Capability Maturity Model Integration) and other frameworks insist that quality departments from the contractor and outsourced provider coordinate and work together, but that may not get into the contract. We don’t seem to understand the difference between a supplier of materials or services that are inputs to our processes vs. BPO which takes over our processes. To get back to the anonymous questioner, if you aren’t getting raw data from your outsourced providers you really can’t evaluate them or come up with an overall quality rating, whether or not you use weighting. When I was asked to do that I told management that I couldn’t do much more than compare how well they claim to be meeting their SLA’s and you already know that. Maybe I could provide some helpful internal data. For instance when we outsourced our IT help desk I could tell them how many complaints and reports of unresolved problems we were receiving. But since I had no insight into their raw data all I could say is make of this what you will.

    0
    #209900

    Strayer
    Participant

    Maybe the real problem here is that you aren’t getting raw quality data from your outsourced providers. I was usually omitted from negotiation of such contracts and then challenged with evaluating them, individually and overall, without the data I needed since they weren’t obligated to provide it.

    0
    #209851

    Strayer
    Participant

    I assume BPO is Business Process Outsourcing. Say 90% is from one source and the other 10% is divided among several others. That’ll exaggerate the other 10% in your final score. Unweighted average of averages might be useful in some circumstances but I can’t think of one. Do you want the average quality of products/services they provide? It’ll be skewed. Do you want to compare the average from one source to the overall average? It’ll be skewed.

    0
    #209850

    Strayer
    Participant

    Your criticism of my zero defects comment is well taken, Mike. The appropriate improvement goal depends on what all the “voices” say, considering cost/benefit, despite what Crosby said in Quality is Free. But have we answered the original question? I took it to mean that he was considering 3 sigma as a “conventional” target but maybe he was asking more about the relation between sigma and z scores, which you addressed in your first response and maybe the rest of us should have let it go at that.

    0
    #209798

    Strayer
    Participant

    The reason zero defects fell out of favor is, of course, that it cannot be achieved. So we chose lesser goals that we could pat ourselves on the back for achieving. There’s a sound argument for “good enough”. That is, what’s good enough for customers to accept. Only our customers can tell us what’s good enough. If we set our own goals based on process capability, cost, or whatever we’re still missing the boat.

    0
    #209498

    Strayer
    Participant

    Crosby noted that the only appropriate goal is zero defects. Say you want 3 sigma (93%) that’s the same as saying your goal is 7% defects, which is crazy. Even if your goal is 99.99% that’s still saying you want to create some defects. That said, you can set lower interim progress goals as long as you understand that continuous improvement doesn’t stop there. We may never get to zero defects but we should never be satisfied with any, even six sigma.

    0
    #208940

    Strayer
    Participant

    Good question. The initial charter is a proposal, not a plan. Some organizations want to make it a project plan that you commit to and require things you won’t know at the beginning, so people fudge things such as metrics, staffing, schedule, budget, etc. To me, the most important part of the charter is the problem statement. Clearly state a specific problem with evidence that it really exists, and it’s cost to the business. That should be enough to get signoff, at least to do the work needed to put together a plan and flesh out the charter to the point your organization requires for a go/no-go decision. That said, most six sigma projects should not be big projects requiring all the rigors of formal project planning. There’s a problem. Let’s find the cause and fix it quickly and cheaply. That’s DMAIC.

    0
    #208802

    Strayer
    Participant

    I’d hoped this might generate some discussion about what we do as professionals. What I do is investigate and understand the problem as best I can. (In this case it was a bur on a plastic part that prevented the safety interlock on the power switch from working and, since it was easily accessible, I filed it down and fixed it myself.) Then I report and clearly explain the problem and offer to help, or point them to where they can get it. With outsourced help desks and poorly written service level agreements, this information may never get to those who need it. But at least I tried rather than just going away as a dissatisfied customer.

    0
    #208285

    Strayer
    Participant

    It sounds like you might be conflating GR&R with calibration. They’re related but different.

    0
    #208238

    Strayer
    Participant

    You can find the answer to this and most other questions by searching this site. It’s probably been discussed before. https://www.isixsigma.com/topic/difference-between-overall-stdev-and-within-stdev/

    0
    #203151

    Strayer
    Participant

    As @mike@darrish.net said we don’t have a governing body for certification. I’ve met people who claimed to be black belts, had no certification, but knew their stuff. I’ve met others who were certified by some organization but were nearly clueless. Wise employers don’t care about certification unless it’s from a highly respected certifying body such as ASQ. Really wise employers care even more about track record and how well you do in interview. Have you tracked down wasteful problems and successfully implemented improvements? That’s what really matters.

    0
    #203149

    Strayer
    Participant

    Well said, Mike. I suggested Brussee’s book because you won’t get through a certification exam or understand many of the tools without knowing statistics. But problem solving is often more about insight and thinking outside the box than doing the math. The most important thing we learn on this journey is how to recognize waste and track down its root causes. Much of the rest is just proving that you were right and that your proposed improvement is actually an improvement.

    0
    #203141

    Strayer
    Participant

    Most books and materials assume that you know the basics you learn to earn a business or engineering degree. I can recommend Warren Brussee’s “Statistics for Six Sigma Made Easy”.

    0
    #203133

    Strayer
    Participant

    Spec limits are set by the customer, or by the next step in the process. Your question should be about the best way to measure it, not how to determine it.

    0
    #203125

    Strayer
    Participant

    American Society for Quality and Indiana Quality Council are good resources for training materials, both introductory and advanced. Do you have entry criteria for the training? Can you assume students have basic understanding of statistics, risk management, and root cause analysis? You need to know what starting level your typical students will have before you can choose, or any of us can recommend.

    0
    #203124

    Strayer
    Participant

    People are not machines. They don’t operate at 100% capacity. Employers require paperwork, meetings, and such. Did you measure actual productive time versus working hours? If you didn’t you shouldn’t be at all surprised.

    0
    #203057

    Strayer
    Participant

    If you’re having to measure all of the potential wastes you haven’t identified a specific problem and you’re trying to boil the ocean. I’d recommend that you take a step back and do a value stream map, or time value map, of the process to identify where and what type of waste is occurring. Choose the most egregious waste point, write a specific problem statement, do your improvement project, remap the process and repeat. That’s continuous improvement.

    0
    #203045

    Strayer
    Participant

    I think you’re missing a key point, John. It’s true that the customer/client sets specification limits but it is your responsibility, not theirs, to assure that variation is within those limits. You shouldn’t be arguing about sample size. Since you’re doing that it suggests that your process is not capable of reliably meeting specifications, and that’s what you need to change.

    0
    #203031

    Strayer
    Participant

    Business process reengineering is groundwork before you tackle IT. For IT I strongly recommend CMMI (Capability Maturity Model Integration). Many IT organizations think they have process maturity when they just have technical expertise and project management. I admit I’m a bit prejudiced after 10 years as an internal CMM/CMMI appraiser for a major corporation and 10 more as an independent consultant before I retired but I’ve seen the difference it can make. I can assure you that forcing BPR and LSS into an immature IT organization is a futile exercise. Complaints about CMMI are that it’s far too bureaucratic (That depends on how well you understand and implement it) and in recent years that Agile works better (The latest version of CMMI incorporates agile methods). Visit the CMMI Institute web site to learn more, and for free download of the models. But you will NOT understand them without training and guidance.

    0
    #203020

    Strayer
    Participant

    Put your data into statistical analysis software such as Minitab, or at minimum into a 3D matrix in a spreadsheet and graph it. If you have questions about what it’s telling you, ask again and someone here will probably help.

    0
    #203006

    Strayer
    Participant

    Although you may do it as a service for a customer, this is not a service industry. You may have no control over the manufacturing process and not be able to improve their process, but that isn’t what you do. Your service is to give them reliable data about the samples they give you. You should apply six sigma to your process for doing that.

    0
    #202999

    Strayer
    Participant

    Define often takes long, not because the problem isn’t clear but because bureaucracy, approvals, strict requirements for charter details, cost/benefit analysis, forming a team, etc. can turn it into a project by itself. You may end up doing DMA just to get through Define. If that’s happening in your organization I’d say you’re suffering from “analysis paralysis” and timidity.

    I’ve often seen projects fail to invest enough time and effort on Measurement. It isn’t enough to just collect data. You need the right data, a significant sample size, and MSA so you can trust your data. But the keyword here is “enough”.

    If you get stuck in Analysis, it’s probably because your problem definition is too broad or you didn’t invest enough in Measurement. Improve can be very short if you’re just tweaking the process or it can be a project by itself.

    Control, in my opinion, is part of Improve since controls should be part of the improvement, not added later. The project ends when the improvements and controls are implemented, but the Control phase never really ends.

    0
    #202993

    Strayer
    Participant

    We often have trouble identifying defect opportunities. As you know, they’re value-added steps in the process where a defect might be introduced. Value-added because by definition a non-value-added step doesn’t change the output. But be careful in service industries. Very often a wasteful step that we’d define as non-value-added actually can introduce a defect. For instance if it delays delivery and the customer has specifications for delivery time.

    Have you done FMEA? It’s one of the best ways to identify where a defect might be introduced.

    As an aside, I have a long-running difference of opinion with many colleagues. I insist that the ratio between potential defects and opportunities must always be 1:1. Otherwise DPMO and sigma level will be skewed. I say that if the ratio isn’t 1:1 you’ve made a mistake in how you identify and count them.

    0
    #202992

    Strayer
    Participant

    No experience with that but I’ve done some auto mechanics. Of course a torque wrench has to be eye-balled by the operator so that’s another variable. Today you can get a digital torque wrench that’s really accurate if properly calibrated. But it sounds like there are more variables in your situation than just torque. It sounds like a poor way to set torque, since you aren’t actually measuring that.

    0
    #202987

    Strayer
    Participant

    Identify what’s different about the bottom layer. For instance, experienced cooks know that it makes a difference whether something is baked in the top or bottom rack of the oven, depending on the design of the oven and other factors. Identify what’s different about the way the bottom layer is processed, from beginning to end. Investigate how each these might affect your specification (strength) and you should be well on your way.

    0
    #202982

    Strayer
    Participant

    Sigma level is the probability that a single measurement will be within specification limits, expressed as the number of standard deviations between the mean and the nearest spec limit. Z-score is the probability of where any single measurement will fall within the distribution of the sample, expressed as the number of standard deviations from the mean, without regard to spec limits.

    0
    #202972

    Strayer
    Participant

    The short answer is yes, they should be controlled. An auditor who finds difference between the pocket cards and the procedure documented elsewhere won’t be pleased. A nit-picker would demand to see the controls in place to ensure that the pocket cards are always consistent with the current version of the official procedure. But as noted by previous commenters, pocket cards may not be the best quick reference. Will people pull out and reference the pocket card?

    0
    #202971

    Strayer
    Participant

    @RogerD Could you share exactly what you want your students to learn from this exercise? It seems to me that the large standard error, it’s implications and potential causes is a worthwhile teaching point. As for what we’d do in industry, as stated in my comments and others: Consistent raw material. Increase sample size. Reduce manufacturing process variation — If I was given this exercise I’d want to find a way to make the clay ball bearings consistent in size rather than just eye-balling it.

    0
    #202956

    Strayer
    Participant

    Re-reading your initial post, you say that the peak is shifted toward a spec limit. If it’s consistently shifted toward either USL or LSL that suggests your modelled process has some sort of bias. Otherwise the wide standard error you’re seeing may result from inadequate sample size. For a pedagogical exercise it may seem impractical to increase sample size but consider that otherwise you may not convincingly demonstrate the fundamentals.

    0
    #202954

    Strayer
    Participant

    I second @diboy89@msn.com It’s called gemba. You want to learn what’s really happening. Observe and document while doing nothing to influence behavior. Granted this can be difficult since if they know they’re being observed employees are more likely to do what they think they’re supposed to do rather than what they normally do. Assuming that you have some data to distinguish high and low performers, make sure you observe both. Often we find that official procedures aren’t followed. Maybe due to poor training or maybe because the procedures don’t work all that well. Maybe top performers have found a better way.

    When you map the current process as observed you’re likely to find variation. Don’t try to average the current process into a single “as is” process map. If you find different processes actually in use, map them all and see what’s different between top performers and others. To validate the map(s) review each only with the people you observed doing it that way. This is the time to ask questions. Why do you do it this way? What else have you tried and why didn’t it work as well?

    0
    #202953

    Strayer
    Participant

    Fair enough. I assume you know that a large standard error suggests there’s something wrong with the model. Maybe someone who’s more expert on statistics will chime in with some better advice. I’d still consider improving control over your raw material so you know they’re starting with a consistent mass/volume ratio. Also, are you giving them some way to measure diameter and sphericality? Without some sort of manufacturing control you’re going to see wide variation.

    0
    #202947

    Strayer
    Participant

    There are a lot of tools and methods to balance supply and demand. All of them require data. So the first thing I’d advise you to do is collect data. It sounds like you’re already on track for doing that. Are the times when demand doesn’t match supply random or is there a pattern? If there’s a pattern that’s something you really need to investigate.

    0
    #202946

    Strayer
    Participant

    The source of variation may be the raw material. The mass/volume ratio of clay can vary considerably due to mineral and water content and since your only specification is mass… And it can change during handling as water content is lost. We know that the output is a function of the inputs but we often forget that and focus on measuring the output, which doesn’t help us to improve all that much.

    0
    #202937

    Strayer
    Participant

    @anvesh The fundamental difference between discrete and continuous data is that discrete has finite values (Yes/No, A,B,C) etc. while the variation between continuous data points is infinite. The more decimal places you can measure, the more different values a data point can have. Consider a histogram, which lumps continuous data together into discrete “buckets”. The output is a function of the inputs. Is the output specification (what the end or internal customer needs) measured as discrete? Yes, because there are upper and lower specification limits, which makes continuous data discrete. So in my opinion all data are ultimately discrete. We cannot measure infinitely small differences. In the end it’s within specifications or it isn’t

    0
    #202914

    Strayer
    Participant

    Just looking at the numbers, this sounds like a study or exam question. Have you done the math? Do you have questions about your answer and methods? Experts on this site will be glad to help with that but we are loathe to do the work for you. In the real world I wouldn’t answer this question without knowing the distribution for your capability data or discussing the customer’s SLA requirements with them.

    0
Viewing 100 posts - 1 through 100 (of 460 total)