Sample size and Sample Qty

[former_member214626]

Hi friends ,

I ahve created a Sampling Procedure with followig data :

Sampling type = SAmple %

Valuatio mode  = manual

Inspection Points :-

Sample mgmt activated .

In the sample size I have mentioned 2% .

Now , I have created a sample drawing Procedure with following data :

No of Primary samples , acc to formulae =  root(lot size) + 1

No of Pooled SAmples , fixed = 1 .

I have attached above SDP in inspeciton plan header with inspection point 200 and the SAmpling procedure to the MIC in plan .

On creating a lot of 100 Litres , I got following :

No of physical samples generated = 12 ( 11 primary and 1 pooled )

In Primary physical sample , :

Sample Qty = .545 Litres and Sample Size = 6L .

and for Pooled physical sample :

Sample Qty = 2 Litres and Sample Size = 6L .

In RR , I am getting this screen :

My doubt is :

1. from where sample qty and sample size in physical sample is being calculated

2. why these qty are different in pooled and physical sample .

3. What thing determine the 2 lines for same MIC in RR .

Please specify clearly as I am new to QM . Thanx in advance

Regards

[former_member207800 · Accepted solution]

I'd like to explain the "sample size" of sampling procedure.

The sample size is not equal to sample quantity.

Acturally the sample size means how many inspection results are required.

The sample quantity is calculated with sample size * base sample quantity (characteristic level in plan).

In your case.. you choose 2% as sample size and lot quantity was 100, so SAP shows 2 line in results recording screen.

(Also you selected "single result" in control indicator of characteristic.)

And as you know already, the physical sample is different with sampling procedure.

Basically the sample drawing procedure is used for physical sample and sampling procedure is used for results recording.

Regards, DoWook KIM

[Former Member]

Answer for third point would be individual sample size of MIC which is derived based on samplng procedure.

In result recording it can be seen that for this MIC sample size is two ,hence system allows you to enter two results based on fixed scope.

[former_member214626]

Hi friends ,

I got answer for point 1 and 2 .

1. sample size for primary sample is being calculated =

(size factor for sample * ( (size of pooled sample) / no of primary samples ) )

2. qty are different because of different size factor in SDP .

size of pooled sample is first calculated using SP .

But 3rd point still pending . can anybody help .

Regards