|
This thread is carried over and continued in the Current Elsmar Cove Forums 
|
|
|
This thread is carried over and continued in the Current Elsmar Cove Forums
|
The New Elsmar Cove Forums
|
 The New Elsmar Cove Forums
 Statistical Techniques and 6 Sigma
 Gage R&R Confidence Intervals
|
 UBBFriend: Email This Page to Someone! |
next newest topic | next oldest topic |
| Author | Topic: Gage R&R Confidence Intervals |
|
Ben unregistered |
posted 21 November 2000 03:40 PM
 
Reference AIAG's MSA Reference Manual, page 95, "Confidence Intervals" Does anyone know of a supplemental text I can go to in order to figure out how to determine confidence intervals for a gage R&R study? I apologize, but I cannot interpret the phrase "where MS denotes percentage point for a mean square distribution (i.e., a Chi-square deviate with the same degree of freedom divided by degrees of freedom, v)" Thank you. IP: Logged |
|
Marc Smith Cheech Wizard Posts: 4119 |
posted 07 January 2001 06:23 PM
 
Any statistical gurus out there with a comment or 2 on this? IP: Logged |
|
max unregistered |
posted 08 January 2001 10:55 AM
The formulas might be in some SPC texts. Here is a journal reference: "Gauge Capability Analysis and Designed Experiments. Part II: Experimental Design Models and Variance Component Estimation" by Montgomery and Runger, Quality Engineering, Vol. 6, No. 2, OCTOBER 1993, pp. 289-305. (part I: Quality Engineering, Vol. 6, No. 1, JULY 1993, pp. 115-135) As for "where MS denotes percentage point for a mean square distribution (i.e., a Chi-square deviate with the same degree of freedom divided by degrees of freedom, v)": if you use ANOVA to get your results from the study, there will be mean squares for part, operator and so on. Each mean square has a specific degree of freedom associated with it. These numbers (the df) are needed to compute the confidence interval. For example, we performed an R&R study with 16 parts. There are 16-1=15 degrees of freedom for the part source of variation in the study. If I wanted to get the 5th percentage point for a Chi-square distribution with 15 df, Excel would give it to me with CHIINV(0.05,15), which is 24.99. Consult the references above. They are written for non-statisticians. IP: Logged |
All times are Eastern Standard Time (USA) | next newest topic | next oldest topic |
  |
Hop to: |
Your Input Into These Forums Is Appreciated! Thanks!
Main Site Search 
