Process Capability Cp Cpk Calculation - Example - Lean Six Sigma the Analysis Phase

[@retroyanfei8944]

Thank you for making this video, live long and prosper.

[@usuitakumi4210]

Thank you ! My professor expects us to find PCR without being given USL and LSL in the scenario question and I was so confused till you said it could NOT be calculated and needed to be given by the design team or deliberately mentioned in the scenario question.

[@shafikhan100]

Hi Dr. Mahmoud, thanks for this video.

[@nathanieltambobe4837]

Hi good work Is there a video with these same data analysis that uses a normal distribution?

[@sreerampillai1339]

Thanks for sharing

[@sihamchlait4383]

Hi thank you for this video I just want to make sure if we calculate standard deviation with the formula we know are we going to get the same one you got here ?

[@dr.mahmoudal-odeh9315]

Not sure if you are going to get the same exact value but I know that you will get a close and accurate value that will help you to calculate the process capability. Try it, compare the two values, and let us know the result.

[@knowledgecentre2907]

please explain more examples. thanks

[@pfny]

Hi, thank you for this i have a question though regarding setting of technical parameter like ph, tss and %salt. Can i use normal distribution in presenting a bellcurve.

[@dr.mahmoudal-odeh9315]

Yes, you can use the normal distribution to represent the bellcurve.

[@baobaluza2823]

At .01 second of the video

[@maceldolaimy4944]

how did you calculate the current lower and upper specification limit? you mentioned it briefly but where did it come from? Thanks in advance

[@summib25]

Nominal value plus tolerance gives you upper specification limit, nominal value minus tolerance gives you lower specification limit

[@dr.mahmoudal-odeh9315]

Specification limits are not calculated it is given to you by the customer or by the design team.

[@aldrichprasmulyan9847]

im sorry, how do u get the d2 = 2.059?

[@shobhak8481]

Where d2 value is available?

[@marvinomarcorpuz8876]

Kindly explain how did you get d2? Can i use the formula of square root of sum of x- x average/n-1 to get the Std Deviation??

[@dr.mahmoudal-odeh9315]

Yes, you can use the formula to get the St. Deviation. d2 is not calculated it is taken from the table in the appendix. Check these websites for the table: www.bessegato.com.br/UFJF/resources/table_of_control_chart_constants_old.pdf web.mit.edu/2.810/www/files/readings/ControlChartConstantsAndFormulae.pdf

[@singhsanjay9997]

Thanks for this chart sir

[@MS-fh4dy]

@@dr.mahmoudal-odeh9315 What should i do if my size group is more than 25 values? How can i find d2?

[@MS-fh4dy]

What should i do if my size group is more than 25 values? How can i find d2?

[@lalo1104]

Hello, I’m doing a project for one of my classes. Did you ever find out what to do about have a group size larger that 25?thanks👍

[@youmeandtheworld]

Yes it was helpful

[@adamdring4555]

At 7:39 how do you find the minimum of them values? What is the formula

[@dr.mahmoudal-odeh9315]

You have to calculate both using the equation given to you and then look at which one is the minimum and you take it as the Cpk.

[@adventures1311]

Hi , here d2= 3.895 . because d2 value will be taken from constant table on sub-group size , but in your example you have 4 sub-groups( X1,X2,X3,X4) and sub-group size will be 24 (each sub group has 24 observed values)

[@shahrirmohammad1027]

can you explain how you get 24?

[@arunkumararo791]

Hello sir can u tell me basically how to find the Value of USL & LSL ? Any formula ?

[@dr.mahmoudal-odeh9315]

No formula for the LSL & USL. These values are not calculated. It is given to you by the design team or taken from the customer. For example, you survey 10 customers and ask them when do they like to get their food in a restaurant. Their answer could be summarized as between 9-16 minutes. So, you consider these (9-16 min) as LSL & USL. So you use these values to do the Cp &Cpk analysis.

[@arunkumararo791]

@@dr.mahmoudal-odeh9315 sir thanks a lot for ur great response and also great example 🙏🙏🙏🙏🙏

[@imaginebeyondlimits]

Sir why sigma value not same ,when we use Excel formula and manual formula.

[@dr.mahmoudal-odeh9315]

Both should be the same value. Check your calculations.

[@Finnift]

If we have number of observation is 1 , than what will be the d2

[@dr.mahmoudal-odeh9315]

If the observation is 1, use the excel function =STDEV.S to calculate the standard deviation. No need to use the d2 equation

[@vinayakramane994]

Sir, How to interpret Cpk if only LSL value available. No USL.

[@dr.mahmoudal-odeh9315]

You need the USL to calculate the Cpk. If you do not have USL you can not calculate the cpk and therefore there is no way to interpret the cpk. If you have a specific example please share it with me so I could look into it in more detail.

[@abhishekchandra8884]

How to check d2??

[@eleven3040]

Why the value of d2 is 2.05?

[@dr.mahmoudal-odeh9315]

www.bessegato.com.br/UFJF/resources/table_of_control_chart_constants_old.pdf

[@boravonmagnesia181]

Es-selamu Aleikum Sir, thank you so much for your efforts on this video, could you please send me , thix excel doc. so that i am able to use for our operations , thanx, i am a master student at quality management departmant in Istanbul, also i am also working as a quality engineer. could u please upload this excel video on this video channel ?

[@dr.mahmoudal-odeh9315]

KZbin doesn't allow to share documents with the video. Send me email at [e-mail] and I will send you the file

[@leocrazy88]

hi, how did you calculate d2?

[@diaaabdulrahmanyoussefmoha87]

It is not calculated, as mentioned in the video, it is (fixed number) in the appendix based on the number of observations you take.

[@dr.mahmoudal-odeh9315]

not calculated it is from the table in the appendix. Check these websites for the table: www.bessegato.com.br/UFJF/resources/table_of_control_chart_constants_old.pdf web.mit.edu/2.810/www/files/readings/ControlChartConstantsAndFormulae.pdf

[@adventures1311]

In your example sub-group size will be 24 by table we have to see 24th value in d2 column.its =3.895

[@loveforever5687]

please show me break down on how to calculate the value of D2.

[@dr.mahmoudal-odeh9315]

d2 is not calculated it is taken from the table in the appendix. Check these websites for the table: www.bessegato.com.br/UFJF/resources/table_of_control_chart_constants_old.pdf web.mit.edu/2.810/www/files/readings/ControlChartConstantsAndFormulae.pdf

[@masyarakatcerdas6963]

Hello Dr Mahmoud could i have your email so that i can contact you. , I want to show you my exercises, and i really need help about the standard deviation. Thank you

[@dr.mahmoudal-odeh9315]

[e-mail]

[@kachyozim2824]

I didn't understand this.

[@sambitkumar6052]

How can we calcluate probability of a targetted Cpk

[@dr.mahmoudal-odeh9315]

not sure! please clarify your question

[@sambitkumar6052]

@@dr.mahmoudal-odeh9315 In a voice process call center all agents have an target to achieve average 125 calls per day , USL 100, LSL-150. Data is normal . hence Cp - 0.95 and Cpk 0.81 with a mean 128.7 delivery team has a question , can we increase the target from 125 to 130. My question is " How can we predict probability of Cp " if we increase the target . Should i use probability distribution plot to check whats the probability of 130 OR we have any better way to check probability of Cp or Yield? i hope i have not confused you. thanks

[@baobaluza2823]

X1 is wrong, compare to the question. It states 12.03 not 12.30

[@dr.mahmoudal-odeh9315]

Where do you see the 12.3? I see the 12.03 as the first value in the X1 column. You should not use individual values in the equations.

[@baobaluza2823]

Why do you think your range on the first row is .29 while the other are below 0.1?

[@dr.mahmoudal-odeh9315]

@@baobaluza2823 got it. Thank you!