interpret sample schema of sample plan table

[Former Member]

Hi guru,

May I know if my following understanding and interpretation on the sample plan table (sampling type is sampling schema) is correct:

Lot Size ---Sample Sze---c1--------d1--------c2 ------ d2------c3-------d3------c4------d4 --------c5---------d5----------c6-----------d6----------c7------------d7
10000----------20--------0----------4--------0---------4-------0---------4------0--------4----------0---------4-----------0------------4------------0-------------0

If lot size is equal or above 10000, the sample size computed by the system will be 20.

The first sample has an acceptance of zero (C1) and rejection of 4 (d1). In another word, if there is 4 or above 4 sample size is fail, it will be rejected. Correct?

Question 1 - what does the zero in C1 means? actually what is the usage of C1, C2, CN means, someone told me it is optional?

Next, if on the first sample, the 4 out of 20 of the sample size are failed, the inspection lot is failed.

Therefore, the system will triggers 2nd sample (i.e. C2, and D2) in which it is similar to C1 and D1 (i.e. 0 for acceptance, 4 for rejection), and if it fail again, the system will trigger the subsequent sample (i.e. C3, and D3) till C7 and D7, correct?

Question 2 - what will the system response if the sample lot kept failing until C6 and D6? Because the last sample (i.e. C7, and D7 are both 0), what will the system do on this?

Thanks

YY

[former_member186399 · Accepted solution]

Dear Yong

Scenario A u2013 There are 2 sample sizes are accepted (i.e. within range), and 3 samples sizes are rejected (i.e. outside lower & upper range)

Scenario B u2013 There are 4 sample size rejected.

Scenario C u2013 There is 3 sample size accepted and 2 sample sizes rejected.

IF under INDEPENDENT MULTIPLE SAMPLE - In this scenario you can record inspection results for individual samples and valuate each sample itself. After the individual samples have been valuated, the system valuates the characteristic using the valuation rule for dependent multiple samples assigned to the sampling procedure.

d. Scenario A ==> system accept it

e. Scenario B ==> system reject it

f. Scenario C ==> system accept it

IF under DEPENDENT MULTIPLE SAMPLE environment - In this scenario you can process double samples and multiple samples (up to seven) in accordance with ISO 2859-1.When you valuate the inspection results, you cannot make a conclusive valuation for the inspection lot, because the number of nonconforming units or defects in the sample determined during results recording lies between the acceptance and rejection number.The system then determines the next sampling plan from the sampling scheme that forms the basis for inspection.

g. Scenario A ==> System proposes for next sampling plan

h. Scenario B ==> system reject it

i. Scenario C ==> system accept it

In addition to above, there are valuation rule associate with independent and dependent multiple sample, what is the valuation rule about?

Valuation rule are nothing but the decider of whether the MIC has to be accepted or rejected

Regards

Gajesh

[Former Member]

Hi Gajesh,

I am getting there (i.e. clearer)

There are three option button to choose during sampling procedure creation:

1 u2013 No Multiple Sample;

2 u2013 Independent Multiple sample,

3 u2013 Dependent Multiple Sample.

So letu2019s say we go back to the previous example:

Lot Size ---Sample Size---c1--------d1--------c2-------d2------c3-------d3------c4------d4 --------c5---------d5----------c6-----------d6----------c7------------d7
10-----------5-------------2---------4---------0-------4-------0---------4------0--------4----------0----------4-----------0------------4-----------0-------------0

Can you give me what response that the R/3 system will trigger on the above three multiple sample choices if undergoing the following three scenarios?

Scenario A u2013 There are 2 sample sizes are accepted (i.e. within range), and 3 samples sizes are rejected (i.e. outside lower & upper range)

Scenario B u2013 There are 4 sample size rejected.

Scenario C u2013 There is 3 sample size accepted and 2 sample sizes rejected.

Therefore:

IF under NO MULTIPLE SAMPLE environment (I believe this is normal inspection right?)

a. Scenario A ==> system accept it, correct right

b. Scenario B ==> system reject it, correct right

c. Scenario C ==> system accept it, correct right

IF under INDEPENDENT MULTIPLE SAMPLE environment (actually what is this multiple sample about?)

d. Scenario A ==> ?? I have no clue

e. Scenario B ==> ?? I have no clue

f. Scenario C ==> ?? I have no clue

IF under DEPENDENT MULTIPLE SAMPLE environment (actually what is this multiple sample about?)

g. Scenario A ==> ?? I have no clue

h. Scenario B ==> ?? I have no clue

i. Scenario C ==> ?? I have no clue

In addition to above, there are valuation rule associate with independent and dependent multiple sample, what is the valuation rule about?

I appreciate your explanation again.

Thanks,

YY

[former_member186399]

Dear Yong

Please let me make the concept clear

1) In normal inspection for sample size 5 with C1 2, D2 4 if the you have accepted 2 and rejected 3 MIC stands accepted.

But if you have activated Multiple sampling (double sampling in Sampling procedure ) system will propose for next sampling and will check for C2/D2.

Hope now you got the clear picture

Regards

Gajesh

[Former Member]

Hi Gajesh,

Thanks so much on your reply, but on the answer 4 which you replied to me, I still have a bit double..

4) Question 2: what if I have 5 sample size, and the actual test result is 2 sample size are pass (which meet C1 value), and 3 sample size are fail (which is smaller than D1 value), I said the whole MIC is pass.. am I correct?
*You said: No, system will propose you to check next sample to check C2 /D2*

Why system propose the next C2/D2? My rational is based on the following statement which you previously confirmed that I am correct:

IF the actual number sample size inspection fall outside the lower & upper limit range (i.e. fail) is Equal to OR Larger than D1, THEN, the whole MIC is rejected.

Thus, my rational is if the above statement is correct, which mean if the failed number of sample size (i.e. 3) is less than d1 (i.e. 4), isn't it clearly pass? Furthermore, out of the 5 sample size, 2 sample sizes are passed (i.e. which is equal to the C1 of 2). Thus, why would the system still propose to check next which is C2/D2? Beside on the very first time, you had replied to me on this topic you saidu2026.

Suppose you have a lot size of 10 having sampling size 5 with C1(acceptance number) 0 and D1(rejection number) 3
You have quantitative MIC with single recording with a specification limit of 10 (lower) to 20 (upper)
If, in actual results, if the 3 of the results is outside the spec limits, the MIC as whole is rejected. If only 2 results are rejected the MIC stands accepted.

The following is the sample plan we talking about...

Lot Size -Sample Size-c1--

---

d1

---

c2---d2--c3---d3--c4--d4 -

---

c5

---

d5

---

c6

---

d6

---

c7--

---

d7

10--

---

5

---

2

---

4

---

0

---

4---0

---

4--0

---

4

---

0

---

4

---

0

---

4

---

0--

---

0

Thanks,

Yong-Yeow

[former_member186399]

Dear Yong

1 ) If the system has rejected MIC at the first instance itself (C1/D1) there is no need of checking for C2/D2 values

2) IF the actual number sample size inspection fall outside the lower & upper limit range (i.e. fail) is Equal to OR Larger than D1, THEN, the whole MIC is rejected, correct?

Yes you are right

3) IF the actual number sample size inspection fall outside the lower & upper limit range (i.e. fail)) is Smaller than D1, THEN, the whole MIC is rejected, correct?

Question 1: should the example you given, i.e. the rejection number of 3 sample size, shouldn't it clearly indicate that the MIC should be pass because it is 3 < 4 (d1)?

No, Multiple sampling u2013 double Sampling is done in this case when a clear valuation of the sample cannot be made because the number of nonconforming units or number of defects in the sample is higher than the acceptance number and lower than the rejection number.

4) Question 2: what if I have 5 sample size, and the actual test result is 2 sample size are pass (which meet C1 value), and 3 sample size are fail (which is smaller than D1 value), I said the whole MIC is pass.. am I correct?

No system will propose you to check next sample to check C2 /D2

Regards

gajesh

[Former Member]

Hi Gajesh,

The following statement from you is quite confusing:

B) If the sample is rejected at C1, system will not propose for next sample. If there is unsurely, system goes for next sampling scheme. For e.g. C1 = 2 D1 =4 and you actual rejection comes to 3, the system can neither accept not reject. In this case system looks for next sample

Therefore, based on the following sample plan:

Lot Size -Sample Size-c1--

---

d1

---

c2---d2--c3---d3--c4--d4 -

---

c5

---

d5

---

c6

---

d6

---

c7--

---

d7

10--

---

5

---

2

---

4

---

0

---

4---0

---

4--0

---

4

---

0

---

4

---

0

---

4

---

0--

---

0

Thus,...

*IF the actual number sample size inspection fall outside the lower & upper limit range (i.e. fail) is Equal to OR Larger than D1, THEN, the whole MIC is rejected, correct?*

*IF the actual number sample size inspection fall outside the lower & upper limit range (i.e. fail)) is Smaller than D1, THEN, the whole MIC is rejected, correct?*

Question 1: should the example you given, i.e. the rejection number of 3 sample size, shouldn't it clearly indicate that the MIC should be pass because it is 3 < 4 (d1)?

Question 2: what if I have 5 sample size, and the actual test result is 2 sample size are pass (which meet C1 value), and 3 sample size are fail (which is smaller than D1 value), I said the whole MIC is pass.. am I correct?

I need to understand this thouroughly

Thanks

YY

[former_member186399]

Dear Yong

Q1

A) Yes you are right .

Suppose you have a lot size of 10 having sampling size 5 with C1(acceptance number) 0 and D1(rejection number) 3

You have quantitative mic with single recording with a specification limit of 10 to 20

If in actual results if the 3 of the results is outside the spec limits the MIC as whole is rejected. If only 2 results are rejected the MIC stands accepted.

B) If the sample is rejected at C1 system will not propose for next sample. If there is unsurity system goes for next sampling scheme. for eg C1 = 2 D1 =4 and you actual rejection comes to 3 system can niether accpet not reject . In this case system looks for next sample

Q2) there will be no case practical when you fail it C7. if it still does means you have to reject the lot. You can affort rejection to reach till c7

Regards

Gajesh