Conducting the "are all points within the control limits" test when there is no LCL?

T

tjkkj

#1
#1
I created an R chart, and it had no LCL. I am conducting runs tests. How do I conduct the "are all points within the control limits" test when there is no LCL? There is one point that is very low on the graph that is concerning me.
 
GAGEpack - Gage & Calibration Management
Elsmar Forum Sponsor
H

harry

Trusted Information Resource
#2
#2
Re: Need help with Runs Test

tjkkj said:
I created an R chart, and it had no LCL. I am conducting runs tests. How do I conduct the "are all points within the control limits" test when there is no LCL? There is one point that is very low on the graph that is concerning me.
Click to expand...
Welcome to the Cove.

Posting your data could go a long way to help people understand your problem before responding.
 
Steve Prevette

Steve Prevette

Deming Disciple
Leader
Super Moderator
#3
#3
Re: Conducting the "are all points within the control limits" test when there is no L

Generally speaking, if you have data that cannot have negative numbers (counting certain things, time to complete something, Ranges in your example) and the LCL mathematically works out to be a negative number, then this means that the chart automatically passes for stability on that criteria.

Let's say you have an event that happens about once a month. Getting a month without the event is nothing special. That is what the negative LCL is telling you - getting a single zero is nothing special. Now, other rules such as 7 points in a row below average (this number varies with author) would allow you to detect a decreasing trend.
 
You must log in or register to reply here.
Thread starter Similar threads Forum Replies Date
M Conducting a clinical investigation with clinical data from India EU Medical Device Regulations 3
W Conducting an MSA Test on scales Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
Sidney Vianna Informational ISO/NP TS 17012 - Guidelines for use of remote methods in conducting audits of management systems Other ISO and International Standards and European Regulations 0
M Lean: Conducting Capacity Study, calculating Cycle times on laser cutting machines Lean in Manufacturing and Service Industries 2
atitheya Need of conducting medical trials in European Union EU Medical Device Regulations 2
M Informational IMDRF draft document – Requirements for Regulatory Authority Recognition of Conformity Assessment Bodies Conducting Medical Device Regulatory Reviews Medical Device and FDA Regulations and Standards News 0
Pmarszal ISO 19011:2018 - Risk Based Approach for planning, conducting and reporting of internal audits Internal Auditing 8
T Results from conducting a Capability Studies Statistical Analysis Tools, Techniques and SPC 4
P Suggestions on conducting Internal Audit of a new site Internal Auditing 15
dubrizo Internal Audit Value - What is the point of conducting internal audits to a checklist Internal Auditing 40
S Conducting an MSA study for ICT(HP3070) and Functional Testing Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
Q AS9100 Repairs - Approval from a non-aerospace customer prior to conducting a repair AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 14
M Conducting a Project for Safety Improvement Misc. Quality Assurance and Business Systems Related Topics 4
A Is conducting of all MSA studies required, even if not required by the customer? IATF 16949 - Automotive Quality Systems Standard 23
B Best Methods for conducting Shadowgraph MSA Studies Quality Manager and Management Related Issues 2
M Sample size when conducting capability analysis with OK and NOK parts Statistical Analysis Tools, Techniques and SPC 3
N Who is responsible for conducting Root Cause investigation? Problem Solving, Root Cause Fault and Failure Analysis 8
H What information do I need to collect when conducting 2nd party audit? General Auditing Discussions 6
drgnrider Suggestions for conducting a Spill Clean-up Exercise Miscellaneous Environmental Standards and EMS Related Discussions 8
O Conducting MSA on Multiple Measurement Mystems Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
C What kind of information you provide when conducting QMS Orientation? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 18
G Conducting a Bias Study for a CMM with no Traceable Master or Reference value Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 4
M Conducting Limited Internal Audits of QMS Elements - Simple question I hope ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 10
K Conducting ISO 9001:2008 and ISO 14001:2004 New Supplier Audit Supplier Quality Assurance and other Supplier Issues 5
D Anyone use an iPad for conducting Audits? Internal Auditing 18
J Need help calculating actual Ppk - Result of % GR&R=11.8% when conducting MSA Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 11
automoto Excel (xlsx) spreadsheet for conducting Type 1 MSA Analysis. Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 23
L Conducting Gap Analysis for ISO 27001 IEC 27001 - Information Security Management Systems (ISMS) 4
A Conducting a DOE in Minitab - Improving Surface Finish of an Impeller Using Minitab Software 10
K Advisable Period of Records to be Checked in Conducting an Audit Food Safety - ISO 22000, HACCP (21 CFR 120) 2
B Conducting a study on Hexagon Nuts "turned" on a multi-spindle automatic lathe Statistical Analysis Tools, Techniques and SPC 9
W Conducting Audit and Audit Report in accordance to 21 CFR 820 and ISO 13485 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 13
Q Design of Experiments Using Subgroup Data - Conducting a 2^3 factorial DoE Quality Tools, Improvement and Analysis 6
M Send a Supplier an Audit Plan prior to conducting an audit at their premises? General Auditing Discussions 8
P Suggestions on conducting an Internal Audit on 7.5.1.6 Production Scheduling IATF 16949 - Automotive Quality Systems Standard 2
D Forms and Templates used for Conducting Internal Audits (API Q1/TS 29001) Oil and Gas Industry Standards and Regulations 5
S Time Study Std/Books that define minimum requirements for conducting time study? Capability, Accuracy and Stability - Processes, Machines, etc. 9
Y Conducting a Mock Recall on a Medical Device Product ISO 13485:2016 - Medical Device Quality Management Systems 6
H Gathering the Data before Conducting GR&R (Gage R&R) Study Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 3
Colin Conducting audits without procedures Internal Auditing 8
J Conducting Gage R&R - 300 plug gauges - Different diameters - One for each plug gage? Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 10
F Conducting an ISO 9001, Clause 5.xx audit General Auditing Discussions 12
T Conducting an Energy Usage Audit - Seeking template or form Miscellaneous Environmental Standards and EMS Related Discussions 3
P Conducting a MSA - Measurement of plaster by use of a scoop - I need Help Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 6
A Goods-In Process Audit - Any pointers or hints for conducting a 'good' audit? Process Audits and Layered Process Audits 3
Marc Conducting Internal Audits vs. Third Party (Registrar) Audits Internal Auditing 11
J ISO 9001 'Compliant' Company - Conducting a supplier audit on a major supplier Supplier Quality Assurance and other Supplier Issues 17
L Conducting general overview training on ISO 14001 Training - Internal, External, Online and Distance Learning 1
R 18 different charts? 18 sample points over 28 days Capability, Accuracy and Stability - Processes, Machines, etc. 13
qualprod How to react when all check points fail? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 34

Similar threads

Top Bottom