101 Things a Six Sigma Black Belt Should Know 
by: Thomas Pyzdek
Topic: Six Sigma Black Belt Qualifications
2/21/2000
101 Things A Six Sigma Black Belt Should Know
By Thomas Pyzdek
This Document is for Electronic Distribution
Only -- REPRODUCTION PROHIBITED --
Copyright © 2000 by Thomas Pyzdek, all
rights reserved
- In general, a Six Sigma Black Belt should be
quantitatively oriented.
- With minimal guidance, the Six Sigma Black Belt should be
able to use data to convert broad generalizations into actionable
goals.
- The Six Sigma Black Belt should be able to make the
business case for attempting to accomplish these goals.
- The Six Sigma Black Belt should be able to develop
detailed plans for achieving those goals.
- The Six Sigma Black Belt should be able to measure
progress towards the goals in terms meaningful to customers and
leaders.
- The Six Sigma Black Belt should know how to establish
control systems for maintaining the gains achieved through Six Sigma.
- The Six Sigma Black Belt should understand and be able to
communicate the rationale for continuous improvement, even after initial goals
have been accomplished.
- The Six Sigma Black Belt should be familiar with research
that quantifies the benefits firms have obtained from Six Sigma.
- The Six Sigma Black Belt should know or be able to find
the PPM rates associated with different sigma levels (e.g., Six Sigma = 3.4
PPM)
- The Six Sigma Black Belt should know the approximate
relative cost of poor quality associated with various sigma levels (e.g.,
three sigma firms report 25% COPQ).
- The Six Sigma Black Belt should know how to
quantitatively analyze data from employee and customer surveys. This includes
evaluating survey reliability and validity as well as the differences between
surveys.
- The Six Sigma Black Belt should understand the roles of
the various people involved in change (senior leader, champion, mentor, change
agent, technical leader, team leader, facilitator).
- The Six Sigma Black Belt should be able to design, test,
and analyze customer surveys.
- Given two or more sets of survey data, the Six Sigma
Black Belt should be able to determine if there are statistically significant
differences between them.
- The Six Sigma Black Belt should be able to quantify the
value of customer retention.
- Given a partly completed QFD matrix, the Six Sigma Black
Belt should be able to complete it.
- The Six Sigma Black Belt should be able to compute the
value of money held or invested over time, including present value and future
value of a fixed sum.
- The Six Sigma Black Belt should be able to compute PV and
FV values for various compounding periods.
- The Six Sigma Black Belt should be able to compute the
break even point for a project.
- The Six Sigma Black Belt should be able to compute the
net present value of cash flow streams, and to use the results to choose among
competing projects.
- The Six Sigma Black Belt should be able to compute the
internal rate of return for cash flow streams and to use the results to choose
among competing projects.
- The Six Sigma Black Belt should know the COPQ rationale
for Six Sigma, i.e., he should be able to explain what to do if COPQ analysis
indicates that the optimum for a given process is less than Six Sigma.
- The Six Sigma Black Belt should know the basic COPQ
categories and be able to allocate a list of costs to the correct
category.
- Given a table of COPQ data over time, the Six Sigma Black
Belt should be able to perform a statistical analysis of the trend.
- Given a table of COPQ data over time, the Six Sigma Black
Belt should be able to perform a statistical analysis of the distribution of
costs among the various categories.
- Given a list of tasks for a project, their times to
complete, and their precedence relationships, the Six Sigma Black Belt should
be able to compute the time to completion for the project, the earliest
completion times, the latest completion times and the slack times. He should
also be able to identify which tasks are on the critical path.
- Give cost and time data for project tasks, the Six Sigma
Black Belt should be able to compute the cost of normal and crash schedules
and the minimum total cost schedule.
- The Six Sigma Black Belt should be familiar with the
basic principles of benchmarking.
- The Six Sigma Black Belt should be familiar with the
limitations of benchmarking.
- Given an organization chart and a listing of team
members, process owners, and sponsors, the Six Sigma Black Belt should be able
to identify projects with a low probability of success.
- The Six Sigma Black Belt should be able to identify
measurement scales of various metrics (nominal, ordinal, etc).
- Given a metric on a particular scale, the Six Sigma Black
Belt should be able to determine if a particular statistical method should be
used for analysis.
- Given a properly collected set of data, the Six Sigma
Black Belt should be able to perform a complete measurement system analysis,
including the calculation of bias, repeatability, reproducibility, stability,
discrimination (resolution) and linearity.
- Given the measurement system metrics, the Six Sigma Black
Belt should know whether or not a given measurement system should be used on a
given part or process.
- The Six Sigma Black Belt should know the difference
between computing sigma from a data set whose production sequence is known and
from a data set whose production sequence is not known.
- Given the results of an AIAG Gage R&R study, the Six
Sigma Black Belt should be able to answer a variety of questions about the
measurement system.
- Given a narrative description of "as-is" and "should-be"
processes, the Six Sigma Black Belt should be able to prepare process
maps.
- Given a table of raw data, the Six Sigma Black Belt
should be able to prepare a frequency tally sheet of the data, and to use the
tally sheet data to construct a histogram.
- The Six Sigma Black Belt should be able to compute the
mean and standard deviation from a grouped frequency distribution.
- Given a list of problems, the Six Sigma Black Belt should
be able to construct a Pareto Diagram of the problem frequencies.
- Given a list which describes problems by department, the
Six Sigma Black Belt should be able to construct a Crosstabulation and use the
information to perform a Chi-square analysis.
- Given a table of x and y data pairs, the
Six Sigma Black Belt should be able to determine if the relationship is linear
or non-linear.
- The Six Sigma Black Belt should know how to use
non-linearities to make products or processes more robust.
- The Six Sigma Black Belt should be able to construct and
interpret a run chart when given a table of data in time-ordered sequence.
This includes calculating run length, number of runs and quantitative trend
evaluation.
- When told the data are from an exponential or Erlang
distribution the Six Sigma Black Belt should know that the run chart is
preferred over the standard X control chart.
- Given a set of raw data the Six Sigma Black Belt should
be able to identify and compute two statistical measures each for central
tendency, dispersion, and shape.
- Given a set of raw data, the Six Sigma Black Belt should
be able to construct a histogram.
- Given a stem & leaf plot, the Six Sigma Black Belt
should be able to reproduce a sample of numbers to the accuracy allowed by the
plot.
- Given a box plot with numbers on the key box points, the
Six Sigma Black Belt should be able to identify the 25th and
75th percentile and the median.
- The Six Sigma Black Belt should know when to apply
enumerative statistical methods, and when not to.
- The Six Sigma Black Belt should know when to apply
analytic statistical methods, and when not to.
- The Six Sigma Black Belt should demonstrate a grasp of
basic probability concepts, such as the probability of mutually exclusive
events, of dependent and independent events, of events that can occur
simultaneously, etc.
- The Six Sigma Black Belt should know factorials,
permutations and combinations, and how to use these in commonly used
probability distributions.
- The Six Sigma Black Belt should be able to compute
expected values for continuous and discrete random variables.
- The Six Sigma Black Belt should be able to compute
univariate statistics for samples.
- The Six Sigma Black Belt should be able to compute
confidence intervals for various statistics.
- The Six Sigma Black Belt should be able to read values
from a cumulative frequency ogive.
- The Six Sigma Black Belt should be familiar with the
commonly used probability distributions, including: hypergeometric, binomial,
Poisson, normal, exponential, chi-square, Student's t, and F.
- Given a set of data the Six Sigma Black Belt should be
able to correctly identify which distribution should be used to perform a
given analysis, and to use the distribution to perform the analysis.
- The Six Sigma Black Belt should know that different
techniques are required for analysis depending on whether a given measure
(e.g., the mean) is assumed known or estimated from a sample. The Six Sigma
Black Belt should choose and properly use the correct technique when provided
with data and sufficient information about the data.
- Given a set of subgrouped data, the Six Sigma Black Belt
should be able to select and prepare the correct control charts and to
determine if a given process is in a state of statistical control.
- The above should be demonstrated for data representing
all of the most common control charts.
- The Six Sigma Black Belt should understand the
assumptions that underlie ANOVA, and be able to select and apply a
transformation to the data.
- The Six Sigma Black Belt should be able to identify which
cause on a list of possible causes will most likely explain a non-random
pattern in the regression residuals.
- If shown control chart patterns, the Six Sigma Black Belt
should be able to match the control chart with the correct situation (e.g., an
outlier pattern vs. a gradual trend matched to a tool breaking vs. a machine
gradually warming up).
- The Six Sigma Black Belt should understand the mechanics
of PRE-Control.
- The Six Sigma Black Belt should be able to correctly
apply EWMA charts to a process with serial correlation in the data.
- Given a stable set of subgrouped data, the Six Sigma
Black Belt should be able to perform a complete Process Capability Analysis.
This includes computing and interpreting capability indices, estimating the %
failures, control limit calculations, etc.
- The Six Sigma Black Belt should demonstrate an awareness
of the assumptions that underlie the use of capability indices.
- Given the results of a replicated 22
full-factorial experiment, the Six Sigma Black Belt should be able to complete
the entire ANOVA table.
- The Six Sigma Black Belt should understand the basic
principles of planning a statistically designed experiment. This can be
demonstrated by critiquing various experimental plans with or without
shortcomings.
- Given a "clean" experimental plan, the Six Sigma Black
Belt should be able to find the correct number of replicates to obtain a
desired power.
- The Six Sigma Black Belt should know the difference
between the various types of experimental models (fixed-effects,
random-effects, mixed).
- The Six Sigma Black Belt should understand the concepts
of randomization and blocking.
- Given a set of data, the Six Sigma Black Belt should be
able to perform a Latin Square analysis and interpret the results.
- Ditto for one way ANOVA, two way ANOVA (with and without
replicates), full and fractional factorials, and response surface
designs.
- Given an appropriate experimental result, the Six Sigma
Black Belt should be able to compute the direction of steepest ascent.
- Given a set of variables each at two levels, the Six
Sigma Black Belt can determine the correct experimental layout for a
screening experiment using a saturated design.
- Given data for such an experiment, the Six Sigma Black
Belt can identify which main effects are significant and state the effect of
these factors.
- Given two or more sets of responses to categorical items
(e.g., customer survey responses categorized as poor, fair, good, excellent),
the Six Sigma Black Belt will be able to perform a Chi-Square test to
determine if the samples are significantly different.
- The Six Sigma Black Belt will understand the idea of
confounding and be able to identify which two factor interactions are
confounded with the significant main effects.
- The Six Sigma Black Belt will be able to state the
direction of steepest ascent from experimental data.
- The Six Sigma Black Belt will understand fold over
designs and be able to identify the fold over design that will clear a given
alias.
- The Six Sigma Black Belt will know how to augment a
factorial design to create a composite or central composite design.
- The Six Sigma Black Belt will be able to evaluate the
diagnostics for an experiment.
- The Six Sigma Black Belt will be able to identify the
need for a transformation in y and to apply the correct
transformation.
- Given a response surface equation in quadratic form, the
Six Sigma Black Belt will be able to compute the stationary
point.
- Given data (not graphics), the Six Sigma Black Belt will
be able to determine if the stationary point is a maximum, minimum or saddle
point.
- The Six Sigma Black Belt will be able to use a quadratic
loss function to compute the cost of a given process.
- The Six Sigma Black Belt will be able to conduct simple
and multiple linear regression.
- The Six Sigma Black Belt will be able to identify
patterns in residuals from an improper regression model and to apply the
correct remedy.
- The Six Sigma Black Belt will understand the difference
between regression and correlation studies.
- The Six Sigma Black Belt will be able to perform
chi-square analysis of contingency tables.
- The Six Sigma Black Belt will be able to compute basic
reliability statistics (mtbf, availability, etc.).
- Given the failure rates for given subsystems, the Six
Sigma Black Belt will be able to use reliability apportionment to set mtbf
goals.
- The Six Sigma Black Belt will be able to compute the
reliability of series, parallel, and series-parallel system
configurations.
- The Six Sigma Black Belt will demonstrate the ability to
read an FMEA analysis.
- The Six Sigma Black Belt will demonstrate the ability to
read a fault tree.
- Given distributions of strength and stress, the Six Sigma
Black Belt will be able to compute the probability of failure.
- The Six Sigma Black Belt will be able to apply
statistical tolerancing to set tolerances for simple assemblies. He will know
how to compare statistical tolerances to so-called "worst case"
tolerancing.
- The Six Sigma Black Belt will be aware of the limits of
the Six Sigma approach.
|