Multi-Vari Analysis

Question 1

Multi-Vari Study/Charts

Answer 1

• Help you identify sources of variation
• Use these charts to see within piece, piece to piece, and time to time variations
• Visually show a variety of sources of variation

Question 2

Variation Sources

Answer 2

• Within piece - variations within a single instance of a product.
  
  • Also known as positional variation
• Piece to piece - variations that occur between different instances of the same product.
  
  • Also known as cyclical variation
• Time to time - variation that occurs at different production times.
  
  • Also known as temporal variation

Question 3

Benefits of Multi-Vari Charts

Answer 3

• Show most of your variations
• Assist you in breaking down the components of variation
• Show all measurements recorded

Question 4

Guidelines for creating Multi-Vari Charts

Answer 4

• Numeric data: You need to be able to plot the effects of variation using mean values
• Factors: Use a maximum of six factors
• Levels: You need at least two levels for each factor
• Amount of data: Collect observations for the majority of factor combinations

Question 5

Creating a Multi-Vari Chart

Answer 5

• Time is on the horizontal (x) scale
• Variable measurement is on the vertical (y) scale