Engineering Talk - DCS's Blog on Quality and Engineering

Brenda Quinlan

Senior Variation Analyst at DCS.

Recent Posts by Brenda Quinlan:

Defects Per Million Opportunities (DPMO) and Z Scores -- Diving into the Six-Sigma Rabbit Hole

Six-Sigma Programs - Using Defects Per Million Opportunities in 3DCS 

Defects Per Million Opportunities (DPMO) is a very important criterion used in Six Sigma programs as an objective and determinant for success or failure. How does DPMO relate and benefit Tolerance Analysis? 

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Topics: CATIA 3DCS Tolerance Analysis T&T SPC Siemens NX 3DCS Creo

Dimensional Analysis: How Many Monte Carlo Simulations Should I Run? Part 2

How Many Simulations Should I Run to Know That I've Run Enough?

Say that five times fast. Seriously, though, how many simulations are enough to be confident that your results are accurate?

 Edited 2-11-2015 for clarity

DCS recommends running 5000 to 20,000 simulations when analyzing a model.

Here is why:

Statistics are estimates of the parameters of a population. 3DCS results are statistics based on a sample (the number of simulations run) of an infinite population (the number of simulations that could be run). Because a statistic is an estimate, the confidence interval is used to determine how good an estimate it is. The confidence interval is calculated from the sample's size and standard deviation and the chosen confidence level (typically 90%, 95%, or 99%).

Topics: 3DCS

What Is a Confidence Interval and Why Is It Important? Part 1

Why Does the Confidence Interval for My Dimensional Analysis Matter?

Confidence intervals provide information about the relationship between the actual statistic for a given simulation and the expected value of the parameter if a simulation had an infinite number of runs.

Topics: 3DCS