Did you know that Minitab provides several tools you can use to
view patterns in data over time? If you want to examine, say,
monthly sales for your company, or even how the number of patients
admitted to your hospital changes throughout the year, then these
tools are for you!
1. Time Series Plot
Time series plots are often used to examine daily, weekly,
seasonal or annual variations, or... Continue Reading
Likert scales are commonly associated with surveys and are used in
a wide variety of settings. You’ve run into the Likert scale if
you’ve ever been asked whether you strongly agree, agree, neither
agree or disagree, disagree, or strongly disagree about something.
The worksheet to the right shows what five-point Likert data look
like when you have two groups.
Because Likert item data are... Continue Reading
Since opening a new
office in Phoenix to support our customers on the West Coast,
some evenings in Minitab technical support feel busier than others.
(By evenings, I mean after 5:30 p.m. Eastern time, when the members
of our tech support team in Pennsylvania go home for the day, and I
become an office of one.)
The variability in terms of days
that felt extremely busy versus days that didn’t... Continue Reading
Allow me to make a confession up front: I won't hesitate to beat
my kids at a game.
kids are young enough that in pretty much any game that is
predominantly determined by skill and not luck, I can beat them—and
beat them easily. This isn't some macho thing where it makes me
feel good, and I suppose is only partially based in wanting them to
handle both winning and losing well. It's just how I... Continue Reading
Most of us have heard a backwards way of completing a task, or
doing something in the conventionally wrong order, described as
“putting the cart before the horse.” That’s because a horse pulling
a cart is much more efficient than a horse pushing a cart.
saying may be especially true in the world of statistics. Focusing
on a statistical tool or analysis before checking out the condition
of your... Continue Reading
In my last post, I discussed how a DOE was
chosen to optimize a chemical-mechanical polishing process in
the microelectronics industry. This important process improved the
plant's final manufacturing yields. We selected an experimental
design that let us study the effects of six process parameters in
Analyzing the Design
Now we'll examine the analysis of the DOE results after the
actual... Continue Reading
I used to work
in the manufacturing industry. Some processes were so complex that
even a very experienced and competent engineer would not
necessarily know how to identify the best settings for the
You could make a guess using a general idea of what should be
done regarding the optimal settings, but that was not sufficient.
You need very precise indications of the correct... Continue Reading
watched television between 1989 and 1993, then you might have had
the chance to see original episodes of the television series
The premise was that a scientist involved in a time-travel
experiment gets sent into the bodies of people from the past and
has the opportunity to improve the future with his actions. Most of
us might not ever get to do something as dramatic as steal a...Continue Reading
Leading and trailing spaces in a data set are like termites in
your house. If you don’t realize they are there and you don’t get
rid of them, they’re going to wreak havoc.
are a few easy ways to remove these pesky characters with Minitab Statistical
Software prior to analysis.
If you’re importing data from Excel, a text file, or some other
Choose File > Open and select
your... Continue Reading
P values have been around for nearly a century and they’ve been
the subject of criticism since their origins. In recent years, the
debate over P values has risen to a fever pitch. In particular,
there are serious fears that P values are misused to such an extent
that it has actually damaged science.
In March 2016, spurred on by the growing concerns, the American
Statistical Association (ASA) did... Continue Reading
When you analyze a Gage R&R study in statistical
software, your results can be overwhelming. There are a lot of
statistics listed in Minitab's Session Window—what do they all
mean, and are they telling you the same thing?
If you don't know where to start, it can be hard to figure out
what the analysis is telling you, especially if your measurement
system is giving you some numbers you'd think are... Continue Reading
Did you know that March is Women’s History
Month? The celebration was started in the 1980s by the U.S.
government to pay tribute to generations of influential women.
To celebrate, here’s a roundup of just some of the most
influential women in statistics:
While Florence Nightingale is known as the founder of modern
nursing, you might not know that she is also a... Continue Reading
Probability. It's really the heart and soul of most statistical
analyses. Anytime you get a
p-value, you're dealing with a probability. The probability is
telling you how likely it was (or will be) for an event to occur.
It has numerous applications across a wide variety of areas. But
today I want to focus on the probability of a specific event.
A basketball tournament.
I’ll be using the Sagarin...Continue Reading
live with a German national, who often tells me that we Americans
spend way too much of our lives at work. He also
frequently comments that we work much less efficiently than Germans
do, during the increased time we’re at work.
Which reminds me—I need to pay my water bill online...
Okay, I’m back. Quick, wasn’t it? So convenient. Now, where was
I? Oh, work habits.
After checking the hourly weather... Continue Reading
There has been plenty of noisy disagreement about the state of
health care in the past several years, but when you get beyond the
controversies surrounding various programs and changes, a great
deal of common ground exists.
agrees that there's a lot of waste and inefficiency in the way
we've been doing things, and that health care should be delivered
as efficiently and effectively as... Continue Reading
I am a bit of an Oscar fanatic.
Every year after the ceremony, I religiously go online to find out
who won the awards and listen to their acceptance speeches. This
year, I was so chuffed to learn that Leonardo Di Caprio
won his first Oscar for his performance in The Revenant in
Awards—after five nominations in previous ceremonies. As a
longtime Di Caprio fan, I still remember... Continue Reading
Like so many of us, I try to stay healthy by watching my weight.
I thought it might be interesting to apply some statistical
thinking to the idea of maintaining a healthy weight, and the
central limit theorem could provide some particularly useful
insights. I’ll start by making some simple (maybe even simplistic)
assumptions about calorie intake and expenditure, and see where
those lead. And then... Continue Reading
After my husband’s most recent visit to the dentist, he returned
home cavity-free...and with a $150 electric toothbrush in
I wanted details.
It began innocently. His dreaded trip to the dentist ended in
high praise for no cavities and only a warning to floss more. That
prompted my programming-and-automation-obsessed husband, still in
the chair, to exclaim, "I wish there was a way to automate... Continue Reading
The easiest way to determine the probability of being born on a
certain day is to assume that every day of the year has an equal
probability of being a birthday. But academic scholarship tends to
point to seasonal variation in births. If you average statistics
from the United Nations, the seasonality in the United States
of America from 1969 to 2013, excluding 1976 and 1977, looks like
Seeing... Continue Reading
Minitab is the leading provider of software and services for quality
improvement and statistics education. More than 90% of Fortune 100 companies
use Minitab Statistical Software, our flagship product, and more students
worldwide have used Minitab to learn statistics than any other package.
Minitab Inc. is a privately owned company headquartered in State College,
Pennsylvania, with subsidiaries in the United Kingdom, France, and
Australia. Our global network of representatives serves more than 40
countries around the world.