Sampling procedures and tables for inspection by attributes can be provided for a given
AQL subject to various switching rules. Custom statistical sampling plans can be developed
for any application at a given level of confidence.
STATS Consulting is implementing a radically innovative approach to Statistical Process
Control and Gage Capability Analysis. Unlike most SPC consulting firms which merely supply
instruction and training, we plan to provide a complete integrated computerized Test
Management System. We feel that SPC procedures can and should be automated by decision
making software, thus eliminating the need for lengthy, costly operator training and
removing the potential for human error.
We propose to implement a computer operated test management system. The test management
system will review SPC control charts and assess for stability and control and perform
trend analysis. The decision making software will perform hypothesis tests based on a data
base which the software itself will compile and maintain. No user input is needed. The
software will assess stability and control independently of specification requirements.
Once stable and within a state of statistical control, the production process may be
addressed for capability and yield optimization.
We use the most statistically powerful UMVUE (Uniformly Minimum Variance Unbiased
Estimators). The less powerful Range Statistic is used in conventional SPC charting only
to simplify the procedure for the operator. Since all calculations are performed by the
computer, we utilize the most powerful statistical algorithms available and are not
subject to calculation errors.
Our Gage Capability acceptance / rejection criteria algorithms are the most innovative
and sophisticated on the market. We assess Gage Capability not only with the traditional
P/T ratio, but also with population sigma analysis and hypothesis testing. Gage acceptance
and rejection is based on tester measurement resolution, not to product distribution. The
decision making software compiles distribution information directly from the product being
measured. This eliminates problems resulting from one sided, unrealistic, incorrect, or
extremely tight specification limits.
Many testers are multivariate, they test many parameters simultaneously. Multivariate
Control Charting and Gage Studies result in n-dimensional ellipsoidal confidence regions.
Such analyses are extremely difficult to perform manually and subject to input error.
These multivariate procedures are simple and robust for automated computer systems.
We can also network your computer based testers to the Test Management System for
automatic downloading. This allows for instantaneously updated tester and process
monitoring, permitting use of all available data for maximized inferential validity.
STATS Consulting also supplies all of the regular SPC and Quality consulting services,
including on site training with our own STATS Data Reduction Software, Multi-lingual
training, Custom Software development, and Custom Statistical consulting for those unique
statistical problems which require derivation of new equations, algorithms, and
procedures.