A
adqmteam
Can anyone tell me the Name of the Control Chart Constants (A2, A3, d2, D3 etc) which are used in calculating the UCL & LCL. 
Can anyone tell me the Name of the Control Chart Constants (A2, A3, d2, D3 etc) which are used in calculating the UCL & LCL.
Not sure what you're asking. The identifiers (A2, etc.) don't have any special meaning in themselves; they're just identifiers, probably more or less arbitrarily assigned.
A
adqmteam
Dear Jim,
thanks for that answer....
If possible i want to know the name of those constants.
We have to mention the name in some presentation.
thanks for that answer....
If possible i want to know the name of those constants.
We have to mention the name in some presentation.
You call them by how they are written... For example, most folks using SPC know what R-bar divided by d2 ("dee two") means. You look at these, and call them in the context of a calculation depending on sample size, etc. If you make a presentation about these factors, show an example of a "table of constants." Virtually all SPC text books have such a table in them.
Stijloor.
Can anyone tell me the Name of the Control Chart Constants (A2, A3, d2, D3 etc) which are used in calculating the UCL & LCL.
Collectively they are called "Unbiasing constants".
..rey
constants are commonly understood by their letter/number designators. Those who are familiar with physics, math, statistics, science will realize there are no "names". Those in the audience who are not familiar with constants likely won't dwell on them long as "names" won't aid in their understanding...
Some 'famous' constants may appear to have names but these are really just well known descriptors (speed of light) , letters (Π - "pi") or in some cases they are associated by the name of the person who developed it.
The constants you are dealing with have little explanatory meaning outside of their formulas.
you can always simply add the descriptor such as A2, Constant for Control Limits for Averages.
Some 'famous' constants may appear to have names but these are really just well known descriptors (speed of light) , letters (Π - "pi") or in some cases they are associated by the name of the person who developed it.
The constants you are dealing with have little explanatory meaning outside of their formulas.
you can always simply add the descriptor such as A2, Constant for Control Limits for Averages.
H
Howard Lee
If I'm asked, I call them "Tabular Constants" and I try hard to look impressive when I say it...lest someone believe that I don't know what I'm talking about.
Somewhere in my damaged memory, I'm thinking that SQCpack had an option to select when you wanted to calculate capability about how to determine Sigma. I believe that you could chelck the option "Calculate Sigma Using Tabular Constants" and it woud return the same results as if you were estimating Sigma using d2.
I think this is where I got the term "Tabular Constants" but my memory is really unreliable and that was a long, long time ago in a place far away.
Somewhere in my damaged memory, I'm thinking that SQCpack had an option to select when you wanted to calculate capability about how to determine Sigma. I believe that you could chelck the option "Calculate Sigma Using Tabular Constants" and it woud return the same results as if you were estimating Sigma using d2.
I think this is where I got the term "Tabular Constants" but my memory is really unreliable and that was a long, long time ago in a place far away.
D
Darius
Agree with all, and if I where asked...
The name is not important, but it's function
Constants to determine economic/natural limits.
The name is not important, but it's function
Constants to determine economic/natural limits.
