Blog posts and articles about using Minitab software in quality improvement projects, research, and more.

The
NBA playoffs are under way, and all eyes are on LeBron James to see
if he can finally bring a championship to Cleveland. But one could
argue that there is even a bigger storyline going on: whether Tim
Duncan can equal Michael Jordan’s six NBA Championships.
Duncan is currently in his 18th season in the NBA,
and he is still playing at a very high level. Yet, he’s never in
the conversation when... Continue Reading

Generally speaking, I have a problem with authority. I don’t
like being told what to do or how to do it. I’m not proud of
that.
I recall debating with my High School Trigonometry
teacher
regarding the value of the homework “process.” Specifically, in
those situations where the student in question did not require
practice to get an A. And, if said student was
getting a 98% on the exams, why spend... Continue Reading

Minitab 17 gives you the confidence you need to improve quality.

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Many of the things you need to
monitor can be measured in a concrete, objective way, such as an
item's weight or length. But, many important characteristics are
more subjective, such as the collaborative culture of the
workplace, or an individual's political outlook.
A survey is an excellent way to measure these kinds of
characteristics. To better understand a characteristic, a
researcher asks... Continue Reading

A while back, I offered an
overview of process capability analysis that emphasized
the importance of matching your analysis to the distribution of
your data.
If you're already familiar with different types of
distributions, Minitab makes it easy to identify what type of data
you're working with, or to transform your data to approximate the
normal distribution.
But what if you're not so great with... Continue Reading

The
2016 presidential race is becoming more real. We’ve had several
announcements with Ted Cruz, Rand Paul, Hillary Clinton, and Marco
Rubio officially entering the race to be President. While the
prospective Democratic candidates are down to one, or at most a
few, the Republican field is extra-large this election cycle. The
first order of business for a GOP candidate is to survive the
nomination... Continue Reading

A few times a year, the
Bureau of Labor Statistics (BLS) publishes a Spotlight on
Statistics Article. The first such article of 2015 recently
arrived, providing analysis of trends in long-term
unemployment.
Certainly an interesting read on its own, but some of the
included data gives us a good opportunity to look at how thought
can improve your regression analysis. Fortunately, Minitab
Statistical... Continue Reading

In 1898, Russian economist Ladislaus Bortkiewicz published his
first statistics book entitled Das Gesetz der keinem
Zahlen, in which he included an example that
eventually became famous for illustrating the Poisson distribution.
Bortkiewicz researched
the annual deaths by horse kicks in the Prussian Army from
1875-1984. Data was recorded from 14 different army corps, with one
being the Guard... Continue Reading

The
Cp and Cpk are well known capability indices commonly
used to ensure that a process spread is as small as possible
compared to the tolerance interval (Cp), or that it stays well
within specifications (Cpk).
Yet another type of capability index exists: the Cpm, which is
much less known and used less frequently. The main difference
between the Cpm and the other capability indices is that the... Continue Reading

The two previous posts in this series focused on manipulating
data using Minitab’s
calculator and the
Data menu.
In
this third and final post, we continue to explore helpful features
for working with text data and will focus on some new features in
Minitab 17.2’s Editor menu.
Using the Editor Menu
The Editor menu is unique in that the options displayed depend
on what is currently active... Continue Reading

My previous post focused on
manipulating text data using Minitab’s calculator.
In this post we continue to explore some of the useful tools for
working with text data, and here we’ll focus on Minitab 17.2’s Data
menu. This is the second in a 3-part series, and in the final post
we’ll look at the new features in Minitab 17.2’s Editor
menu.
Using the Data Menu
When I think of the Data menu, I think... Continue Reading

With Minitab, it’s easy to create graphs and manage numeric,
date/time and text data. Now Minitab 17.2’s enhanced data
manipulation features make it even easier to work with text
data.
This
is the first of three posts in which I'm going to focus on various
tools in Minitab that are useful when working with text data,
including the Calculator, the Data menu, and the Editor menu.
Using the Calculator
Y... Continue Reading

As a member of Minitab's Technical Support team, I get the
opportunity to work with many people using DOE (Design of
Experiments).
People often will call after they've already chosen their
design, run the experiment, and
identified the important factors in their process. But
now what? They have to find the best settings, but with
several factors and responses, what should they do?
"I wish I had
a... Continue Reading

In this series of posts, I show how hypothesis tests and
confidence intervals work by focusing on concepts and graphs rather
than equations and numbers.
Previously, I used graphs to show what statistical significance really
means. In this post, I’ll explain both confidence intervals and
confidence levels, and how they’re closely related to P values and
significance levels.
How to Correctly... Continue Reading

Minitab 17.2 is available. You can check out all of the new
stuff on the What’s New
Page, but I would say that a little demonstration is in order.
Here are some new shortcuts that make arranging your data easier in
Minitab 17.2.
Sorting
Let’s suppose that you had copied some Human Development Index data into
Minitab and wanted to sort countries in the order of their rank. In
the past, you would have... Continue Reading

To choose the
right statistical analysis, you need to know the distribution of
your data. Suppose you want to assess the capability of your
process. If you conduct an analysis that assumes the data follow a
normal distribution when, in fact, the data are nonnormal, your
results will be inaccurate. To avoid this costly error, you must
determine the distribution of your data.
So, how do you determine... Continue Reading

Imagine that you are watching a race and that you are located
close to the finish line. When the first and fastest runners
complete the race, the differences in times between them will
probably be quite small.
Now wait until the last runners arrive and consider their
finishing times. For these slowest runners, the differences in
completion times will be extremely large. This is due to the fact
that... Continue Reading

by Lion "Ari" Ondiappan Arivazhagan, guest blogger.
Predicting project completion times is one of the major
challenges project managers face. Project schedule overruns are
quite common due to the high uncertainty in estimating the amount
of time activities require, a lack of historical data
about project
completion, organizational culture, inadequate skills, the complex
and elaborative nature of... Continue Reading

This is a companion post for a series of blog posts about
understanding hypothesis tests. In this series, I create a
graphical equivalent to a 1-sample t-test and confidence interval
to help you understand how it works more intuitively.
This post focuses entirely on the steps required to create the
graphs. It’s a fairly technical and task-oriented post designed for
those who need to create the... Continue Reading

I always knew I was different. Even as a kid.
“Is that me? Way out there in left field?” I asked the doc.
“Yes,” he nodded, as he looked at my chart. “I used brushing to
identify you on the graph.”
I wasn’t sure I liked getting brushed. It felt like my true
identify was being detected and displayed in a window for all to
see.
The doctor must have sensed my discomfort.
“It’s not uncommon—even for those... Continue Reading

Monte Carlo simulation has all kinds of
useful manufacturing applications. And - in celebration of
Pi Day - I thought it would be
apropos to show how you can even use Monte Carlo simulation to
estimate pi, which of course is the mathematical constant that
represents the ratio of a circle’s circumference to its diameter.
For our example, let’s start with a circle of radius 1 inscribed
within a... Continue Reading