SBS - The Best Value in QMS software

SPC Statistical Process Control with All data

O

ozkaynakm

#1
Hi,

I can obtain all the data of a measured process. The metric is "order delivery period". There is an upper specification limit regarding this process. The lower is not important.

Is it reasonable to perform and interpret I-MR or X-Bar Control Analysis for this process giving all the data instead of sampling?
How can provide a substantial reasoning to this analysis?

The data belongs to different dealers. Although there is upper specification limit, Everytime, It is not possible to work in accordance with this specification.
Yes, we can see the data which are above the USL. However, along with this, we also target to catch the special causes [especially found above UCL] and argue the causes. Is it recommended?
Best regards,
Okan Ozkaynak
 
Elsmar Forum Sponsor

Bev D

Heretical Statistician
Staff member
Super Moderator
#2
Of course you can use SPC approaches to determine if a process is "out-of-control" vs "out of spec" to identify special causes. The S in SPC stands for statistical not sampling. There is no requirement, constraint ro prohibition regarding sample size. In fact many of my most useful and important control charts involve 100% data, not samples.

That said, I can't predict which chart is most applicable without seeing the data...
 
O

ozkaynakm

#3
Thank you very much for your understandable and clear information. This sharing made me comfortable :)
Regarding which type of chart should be used?...
Our process is not a production process. It is a sales and logistics processes. I am a blackbelt passing from production site to sales and logistics operations. Because of this, I try to make analogy between these businesses. In order to monitor and then query the special causes during delivering processes of our dealers I've selected to apply this statistical tool. My data set is as one column as follows;
for ex:
Dealer Date and Time Order Delivery Period
A 01.01.2010 08:34 40 min
A 01.01.2010 09:45 32 min
A 01.01.2010 11:43 22 min
A 02.01.2010 10:32 11 min
. ... ...
. ... ...
. ... ....
. ... ....
Thanks in advance...
 

reynald

Quite Involved in Discussions
#4
I too use 100% data in most of my SPC charts (since they are available anyways), but I prefer to use I-MR rather than Xbar-R/Xbar-S for these cases two reasons:
1. The spc constants used for Xbar-R/Xbar-S assumes sampled data are being plotted. In fact the higher the sample size, the tighter the control limits are due to the relationship S/sqrt(n).
2. Using Xbar-R/Xbar-S with varying sample sizes is very messy and tedious (at least for me). If I can assume that I am plotting the mean and the sigma of population data, then I can simply treat the means and the sigma as individual "measures" and use I-MR. I does simplify things.
 

bobdoering

Stop X-bar/R Madness!!
Trusted Information Resource
#5
Regarding which type of chart should be used?...
Our process is not a production process. It is a sales and logistics processes. I am a blackbelt passing from production site to sales and logistics operations. Because of this, I try to make analogy between these businesses.
If you are going to use SPC as your tool, have you taken the first step of applying this technique? You probably were not taught this, so I am going to help you out. You need to develop an estimate of the total variance equation. This encourages you to think of what it is you are measuring, what variation is occurring, the fact that your output is a combination of several sources of variation - and rarely one. As a result, it will likely be multimodal, not the clean, simple normal distribution most people expect (because they think they are only measuring one source of variance.) You need to determine what variation is: noise, controllable (and is can be eliminated or reduced to a statistically insignificant level) and experimental (adjustable to optimize). This is very similar (and related) to a CNX analysis, but focused on the measureables and their expected distributions.
 
Thread starter Similar threads Forum Replies Date
Marc Steve Prevette's Statistical Process Control (SPC) "Library" Statistical Analysis Tools, Techniques and SPC 0
S SPC (Statistical Process Control) for Unilateral Tolerance - Questions Statistical Analysis Tools, Techniques and SPC 6
O Is SPC (Statistical Process Control) always required? Statistical Analysis Tools, Techniques and SPC 4
M SPC (Statistical Process Control) Book Recommendations wanted Book, Video, Blog and Web Site Reviews and Recommendations 1
I How to use Statistical Process Control (SPC)? Statistical Analysis Tools, Techniques and SPC 8
J Definition Control - Definition of Control in SPC (Statistical Process Control) Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 8
T Recommend books on SPC (Statistical Process Control) Statistical Analysis Tools, Techniques and SPC 3
S SPC (Statistical Process Control) books - Suggestions and reviews please Book, Video, Blog and Web Site Reviews and Recommendations 3
J What SPC (Statistical Process Control) software is your company using? Statistical Analysis Tools, Techniques and SPC 15
T Touch Screen Capable Software suggestions for SPC (Statistical Process Control) Quality Assurance and Compliance Software Tools and Solutions 4
H Getting A Supplier to use SPC (Statistical Process Control) Supplier Quality Assurance and other Supplier Issues 5
P ISO 9001 requirement for SPC (Statistical Process Control) ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 7
Batguy SPC (Statistical Process Control) on Go/No-Go Checks Statistical Analysis Tools, Techniques and SPC 18
M SPC (Statistical Process Control) analysis and status on two manufacturing plants Statistical Analysis Tools, Techniques and SPC 4
V Statistical Process Control (SPC) for Clean Room Environments ISO 13485:2016 - Medical Device Quality Management Systems 6
V SPC (Statistical Process Control) for Medical Device Company Statistical Analysis Tools, Techniques and SPC 4
J Learning Statistical Process Control - I need a crash course in SPC Statistical Analysis Tools, Techniques and SPC 8
C Starting a Small Lot SPC (Statistical Process Control) program Statistical Analysis Tools, Techniques and SPC 8
I SPC (Statistical Process Control) and SQC (Statistical Quality Control) - Difference? Statistical Analysis Tools, Techniques and SPC 1
R SPC (Statistical Process Control) for Unilateral Tolerance Statistical Analysis Tools, Techniques and SPC 10
S SPC (Statistical Process Control) - I have data, now what? Statistical Analysis Tools, Techniques and SPC 14
S Reaction Plan for SPC (Statistical Process Control) Chart Statistical Analysis Tools, Techniques and SPC 4
M Is SPC (Statistical Process Control) useful? Statistical Analysis Tools, Techniques and SPC 72
C SPC (Statistical Process Control) software recommendations Quality Assurance and Compliance Software Tools and Solutions 23
J User Friendly SPC (statistical process control) Software Quality Assurance and Compliance Software Tools and Solutions 14
Tim Folkerts Is it Time for New Rules for SPC (Statistical Process Control)? Statistical Analysis Tools, Techniques and SPC 22
C SPC (Statistical Process Control) for Management Reports Statistical Analysis Tools, Techniques and SPC 2
Marc Definition Statistical Process Control (aka SPC) - Definition Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 0
Q AIAG Releases the 2nd Edition of their SPC (Statistical Process Control) Manual Statistical Analysis Tools, Techniques and SPC 19
J ISO 9001:2000 - SPC (Statistical Process Control) requirements Statistical Analysis Tools, Techniques and SPC 4
Steve Prevette SPC (Statistical Process Control) Overview Statistical Analysis Tools, Techniques and SPC 101
L Defining Pre-Control Zones - Statistical Process Control (SPC) Statistical Analysis Tools, Techniques and SPC 1
S AIAG Statistical Process Control (SPC) Manual - Page 81 Statistical Analysis Tools, Techniques and SPC 4
M Predictive Maintenance vs SPC (Statistical Process Control) Data Misc. Quality Assurance and Business Systems Related Topics 3
D ISO 11462-1 Guidelines for implementation of Statistical Process Control (SPC) Statistical Analysis Tools, Techniques and SPC 4
T I need an add-in for excel that I can use for SPC (Statistical Process Control) Excel .xls Spreadsheet Templates and Tools 4
Raffy Statistical Process Control - ISO 11462-2:2001 Key elements of an SPC System Statistical Analysis Tools, Techniques and SPC 1
K SPC (Statistical Process Control) Training and Courses - Seeking suggestions Training - Internal, External, Online and Distance Learning 2
Marc SPC (statistical process control) charts and SD (System Dynamics) models Preventive Action and Continuous Improvement 18
J Statistical Significance and SPC Control Chart Reports Statistical Analysis Tools, Techniques and SPC 9
I SPC Statistical Analysis in Metrology General Measurement Device and Calibration Topics 2
V Which Statistical Tool for Pressing Components other than SPC Statistical Analysis Tools, Techniques and SPC 5
A P & F value in Minitab Statistical Studies (SPC) and the 8 points rule Using Minitab Software 7
A SPC Training - I want to develop my knowledge in statistical tools Statistical Analysis Tools, Techniques and SPC 5
B Statistical Analysis SPC Trend explanation needed Statistical Analysis Tools, Techniques and SPC 4
I Statistical Tools outside of SPC Statistical Analysis Tools, Techniques and SPC 2
W SPC all the time? Does QS9000 require statistical control on all processes? QS-9000 - American Automotive Manufacturers Standard 3
C Buying Minitab / other SPC or Statistical software Quality Tools, Improvement and Analysis 8
G Need journal and reference of abnormal bar chart SPC Statistical Analysis Tools, Techniques and SPC 3
Q CQI-26 SPC Short Run Supplement Capability, Accuracy and Stability - Processes, Machines, etc. 1

Similar threads

Top Bottom