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Lean Six Sigma Certification Game

A friend and colleague, Bill Bentley, writes about the use of professional certifications in the recruiting industry.

I had a long talk with a senior IT professional in Chicago last week expressing his deep frustration that despite his long and distinguished professional career, he could not get interviews without certain certifications despite being able to teach the topics himself.

Many of you looking for jobs are facing the same problem whether you know it or not. Certifications are being used to screen out candidates because of the huge numbers of applicants. An $8/hr person or worse, a computer program, is being used to scan resumes into the little pile that the hiring manager will look at and the big pile that gets thrown away.

Certifications which are being used A LOT for this purpose are Six Sigma, Lean, PMP and increasingly in the IT field, ITIL. In some cases the companies truly want these skills but in many cases they are nothing more than `wish list’ skills and objective facts that can be easily used by the resume screener for sorting.

If the jobs that you look at have these topics listed in the job descriptions you can be quite sure that without them, your resume is much more likely to end up in the big pile than the little pile. …

So do you really need that certification just to get the job? Often an organization is trying to upgrade its bench strength by requiring certification, but how do you know it’s not just a charade and a meaningless recruiting filter. Maybe you want to be sure your prospective employer is serious, and that might take some digging and fortitude to be able to walk away from a company that’s just pretending.

Forget the 80/20 Rule

In the late 1800s, economist and avid gardener Vilfredo Pareto established that 80% of the land in Italy was owned by 20% of the population. While gardening he later observed that 20% of the pea pods in his garden yielded 80% of the peas that were harvested. And thus was born a theory that has stood the test of time and scrutiny. The Pareto Principle or the 80:20 Rule has proven its validity in a number of other areas:

80% of sales come from 20% of your customers (definitely true in our case)
20% of your products account for 80% of your sales
A small percentage of the population generate the largest health care costs
Earnings come from 20% of your investments
80% of this blog’s traffic is to 20% of the postings (actually 33 pages of 180, or 18.3%)

We’ve learned to categorize and sort our defects, problems, expenses by this 80/20 rule so that we can focus or limited resources, attention, brain power on the ‘vital few’.

But in my experience you can’t let this thinking allow you to forget about the tail. Often the greatest opportunities or insights are found are out there in the mix.

EVOP – Evolutionary Operations

Evolutionary Operations, first described by George E. P. Box and Norman R. Draper in in their book Evolutionary Operations – A statistical method for process improvement, New York: John Wiley and Sons, 1969.

EVOP is Continuous Improvement + Design of Experiments.

Basic idea is to replace the routine operation of a process by continuous and systematic plan of slight adjustments of the control variables. The effects of the adjustments are then evaluated just as with DOE. The process is then shifted in the desired direction of improvement. In many product and service processes it is impossible or very expensive to do DOE, especially where trials can be disruptive or the process owner would let you have the necessary time, materials, labor to run your experiments. So rather than running experimental production runs you use actual production by shifting off the base point left, right, up, down all within "spec".

Continue reading EVOP – Evolutionary Operations

Fixed Repeating Schedule – Product Family Turnover Rate

Here’s another example for “sizing the wheel” for a mixed model fixed repeating schedule.

Given:

Changeover Time = 100 minutes
Available Production Time = 2 shifts * 7 hrs/shift * 60 min/hr = 840 min/day

and

Product	Daily Demand (pcs)	Cycle Time (min.)	Load (min.)
A	80	5	400
B	40	4	160
C	20	4	80
D	10	6	60
			700

Now some math:

Total Load = 700 min.
Time Available for Changeovers = 840 min/day – 700 min/day = 140 min/day
Changeover Time for group = 100 min * 4 products = 400 min/family
Changeovers per day = 140 min/day / 400 min/family = 0.35 group/day or a Replenishment Time of 2.85 days/family

So the fixed repeating wheel will turn once in 2.86 days. Production run sizes as follows: