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Multi-Vari Analysis

Multi-Vari is the perfect tool to determine where variability comes from in your process (lot-to-lot, shift-to-shift, machine-to-machine, etc.), because it does not require manipulating the independent variables (or process parameters) as you would with design of experiments.

Once you have determined where the major source of variability comes from, then you target your experimental designs (DOE) more efficiently to reduce that particular source of variation.

Book Description Benefits
Multi-Vari Chart and Analysis is the first book that describes how to compute a standard deviation (or variance) for each source of variability in your process. This is accomplished by statistically analyzing Multi-Vari chart data, using analysis of variance and variance decomposition.

Multi-Vari charting is presented as a pre-experimentation technique designed to isolate and quantify the major components of variability in production processes, including vendors' and suppliers' processes.

  • Follow a step-by-step approach to construct Multi-Vari charts, to implement them and to analyze their data statistically.
  • Learn how to uncover the major sources of variability of your suppliers' and vendors' data using Multi-Vari Statistical Analysis.
  • Discover the components of variation in your process and quantify the different sources:
    • Within shift
    • Between shift
    • Shift-to-shift
    • Lot-to-lot
    • Within lot
    • Machine-to-machine
    • Within operator
    • Operator-to-operator
    • Between operators
    • etc...

Book: Multi Vari Analysis
Availability Table of Contents
  • Pages: 98
  • Current Edition: 2014
  • ISBN: 1-883237-01-7
  • Available with seminar attendance
  • Introduction
  • Multi-Vari Chart Description
    • Family of Variation
    • Positional Variation
    • Cyclical Variation
    • Temporal Variation
  • Construction of a Multi-Vari Chart
    • Determining the Limits of Variation
    • Determining the Sampling Scheme
    • Graphing the Ranges
    • Analyzing the Chart
  • Statistical Analysis of Multi-Vari Charts
    • Estimating Positional Variation
    • Estimating Cyclical Variation
    • Estimating Temporal Variation
  • Analysis of Variance of Multi-Vari Charts
    • Across Time Sum of Squares
    • Between Piece Sum of Squares
    • Within Piece Sum of Squares
    • Components of Variation
    • Expected Mean Square Computation
  • Case Studies
    • Computer Manufacturer
    • Fuel Injection Manufacturer
    • Medical Product Manufacturer
  • Appendix
    • Statistical Tables
  • References
  • Index
Factum
Multi-Vari is not a Dorian Shainin technique as many believe, it was first developed by Leonard Seder back in 1950.

The tool was always used as a chart, until this book, which described for the first time how to breakdown the data and quantify and isolate each variance statistically.