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Take control of your processes with Minitab's suite of control charts and powerful SPC capabilities
Minitab offers many tools to help you detect problems in your processes. SPC tools like control charts allow you to keep track of process statistics over time and identify the special causes that might threaten your procedure. Visit http://minitab.com/products/minitab/
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A Simple SPC Alternative
Sometimes the simplest way to test statistical independence is with a simple diagram. From Quality Digest, written by Thomas Pyzdek.
Case Study: Using np Charts To Address On-Time Medication Delivery
Quality improvement is not simply data gathering, but analyzing data and organizing it in order to determine ways to improve the process. np Charts coupled with a pareto analysis can help the user improve process quality. From Michael J. Cleary, Ph.D. and iSixSigma.
Control Chart Basics
Basic components, what to look for, types of errors and special cause versus common cause. From Skymark.
Control Limits Recalculation
Here are some guidelines for when you should recalculate control limits. From PQ Systems.
Explaining Run Charts
How and why do we make a Run chart and what is its significance? From iSixSigma Discussion Forum.
From Quality Control To Quality Improvement
From Quality Control to Quality Improvement is a case study in applying control charts and experimental design. From Marc Schaeffers and iSixSigma.
How Much Don't You Know?
Statistical data may just show that you don't understand your process at all. From Quality Digest, written by Thomas Pyzdek.
I Hate SPC
Pinning down one special cause after another might just make a believer out of you. From Quality Digest, written by Thomas Pyzdek.
Integrating SPC and SQC to Overcome Weakness in Either
SQC and SPC are two powerful tools, which have different goals and requirements for successful application. By using a methodology that combines the strengths of both approaches, it is possible to overcome the individual weaknesses of each one. From Marc Schaeffers and Craig Stephen.
Make Valid Control Chart and Subgroup Assumptions
Four real world case studies that display how incorrect assumptions can lead to invalid control charts and improper statistical process control (SPC). Don't make these same control chart and subgrouping mistakes. From iSixSigma.
Median Control Charts
Median control charts bridge the gap between individuals charts and averages charts. From Quality Digest, written by Thomas Pyzdek.
Multiple Control Limits?
When to throw out the old and go with the new. From PQ Systems.
Preventing Hospital Falls with SPC
Hospitals can take data and plot hospital falls to see if they are in 'control.' Other tools can then be overlaid to reduce process defects. From Quality Digest, written by Thomas Pyzdek.
Recalculating Control Limits
The tedious task of analyzing control charts for validity of the limits can be eliminated and the resulting report can be used as a tool to keep the process of continuous improvement on track. From Marc Schaeffers and Craig Stephen.
Run Charts
Display your process performance over time. Here are some alternatives, questions to ask when viewing, mistakes to avoid and pointers to look for special cause variation. From Skymark.
Should You Use A Mean Or Individuals Control Chart?
To plot individual data or to group the data and plot the mean on a control chart, that is the question. This article helps you understand how to make the most of your data. From John J. Flaig and iSixSigma.
SPC and Global Warming
Has global warming exceeded our control limits? From Quality Digest, written by Thomas Pyzdek.
The Impact of Control Strategies on Z Shift Values
When special control strategies are applied to typical process data, the observed relationship between Z(short-term) and Z(long-term) is reproduced, and a relationship to estimate Z(short-term) from Z(long-term, discrete) from defect counts is derived. From Alastair Muir.
What Is A Stable Process?
Process stability is one of the most important concepts of any quality improvement methodology. Stable processes involve achieving consistent and, ultimately, higher process yields through the application of an improvement methodology. Learn more about stability. From iSixSigma.
When Do I Recalculate My Limits?
Correct limits allow the user to separate probable noise from potential signals. From Quality Digest.
When in Doubt, Get the X Chart Out
X charts can be used to plot percentages, ratios, counts and other nonmeasurement data, even when the assumptions are only approximately met. From Quality Digest, written by Thomas Pyzdek.
Why Control Chart Your Processes?
Control charts help you identify and understand process variation. Learn the major elements and control charts and how to construct a control chart. From Kerri Simon and iSixSigma.
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