Mayank Gupta

Hello Ankit Since you mentioned rejections, I am assuming that you are considering Defectives. Hence you will consider the Defectives and total quantity of transactions (or items produced) to calculate Yield and subsequently the Sigma Level. You may refer to the calculator at the below link to calculate Sigma Level https://www.benchmarksixsigma.com/calculators/sigma-level-calculator-discrete-data-defectives/

Hi Vaishali Please elaborate on the intent. Currently it is unclear on what's the objective.

Hi Hemant Usually targets are given by the customers. If you are the customer and are unaware of the targets, you could probably look at your competitors or if there is a regulatory requirement for accuracy target. As a last resort and if none of the above works, then you could also set the target by looking at the process performance. Hope this helps.

Hi Larry Good to have you on our forum. It is always our endeavor to help forum members learn and grow. Accordingly we put two questions every week and seek answers from the forum fraternity. The current open question is at the below link https://www.benchmarksixsigma.com/forum/topic/35525-box-plot/ These questions are asked every Tuesday and Friday. Do attempt these questions in order to gain insights on tools and learn.

This was a slightly tricky one as the question was about why the Sigma Level or the Z score is the preferred metric for process baselining and not about what it is. The best answer has been provided by Vastupal Vashisht for highlighting the benefits of using the Sigma Level. Do read the response from our in-house expert to get more insights as to why the Sigma Level calculation is so popular.

Hi Devang Good observation. Lean Six Sigma tools can help in removing the Non-Value adding activities being performed by Supplier Management in order to avoid duplication / rework / rechecks etc. It can also help in reducing the cycle time and wait times in Supplier management tasks in order to reduce the overall Lead Time

Hi Duy There are two parts to your question. Let me try answering it part wise. Part 1 - whether bias should be compared against the reference value or the specification? During a Gage study, bias is observed in the complete range of the gauge with repeated observations. Simply stated it gives you an indication of the central tendency of the observations. This central tendency of the observations should be compared with another central tendency which in this case becomes the reference value (you may also understand the reference value as the target value). The problem with comparing it with specification is that it will not be like to like comparison. Let us take an example - suppose you are doing a gage R&R for measuring the inner diameter of a bolt. The reference value (or target) is 2.5 mm and specifications are +/- 0.1 mm. You picked a sample of 5 such bolts and did 12 trails with the operators and the study suggests that there is a bias of 0.05 mm i.e. the observed value is greater than the actual by 0.05 mm. Now if you compare it with the target, you are still within specification, however if you compare it with the specification, you might end up rejecting good bolts as well. Hence, the bias should always be compared to the reference or the target value and not with the specification. Part 2 - In cases where bias is large (>10%) and bias/specification < 10%, can the bias be accepted? Ideally speaking you should NOT accept the bias if is greater than 10%. You should first fix the measurement system. However, practically, in some projects, you may choose to accept the bias under the following conditions 1. There is only 1 sided specification limit (because in two sided specification limits, if you do not address the bias, it will start impacting the process capability as your reference value is improved) 2. Specification is too high even for the revised reference value (or the revised target) + the bias E.g. Let us assume, the moisture in a powder compound cannot exceed 13%. Your current reference value is 8% and the measurement system has a bias of 1%. If your target is 10%, you may choose to ignore the bias as you will not breach the specification of 13% with 1% bias. However, if you target is 12.5%, then you will definitely need to fix the bias before improving the process Hope this helps.

Hi Akshay As I had mentioned in my previous comment, the calculation of sum and sumsq and using it to calculate the standard deviation is not right.

Hello Akshay I am not a coding expert in C#. However, looking at the code, I guess the issue is with the calculation of Mean and Standard Deviation. With reference to your code....could you please help me understand what is happening in the highlighted steps ****************** foreach (DataRow Row in dt.Rows) { Double delta = double.Parse(row["USL"].ToString()) - Double.Parse(row["LSL"].ToString()); sum += delta; sumsq += delta * delta; } double mean = sum / dt.Rows.Count; double stdev = Math.Sqrt(sumsq / dt.Rows.Count - mean * mean); ****************** Per my understanding, for each row in the table, you are first calculating Delta = USL - LSL and then updating 'sum' and 'sumsq'. Is it correct? If that's the case, then your mean and stdev calculations are incorrect and therefore you are getting incorrect Cp and Cpk values. And your formula for stdev also seems to be incorrect. Also, I looked at the CSV file. USL says 7.25 while LSL says 8. This seems to be incorrect. USL has to be higher than LSL. So you need to fix your inputs as well. Plus, you don't need to create the code for this calculation. You can refer to our Cp/Cpk calculator at the following link. Enter the values for mean, standard deviation, LSL and USL and you will get Cp and Cpk https://www.benchmarksixsigma.com/calculators/process-capability-calculator/ Though you will not be able to upload a CSV file, but you can simply calculate the mean and stdev for Test column and enter the values in the ready to use calculator.

Q. 150 Using the Sample Size Calculator for 1 Sample T-Test at https://www.benchmarksixsigma.com/calculators/sample-size-calculator-for-1-sample-t-test, highlight the factors which affect the sample size determination by using some examples.  Please remember, your answer will not be visible immediately on responding. It will be made visible at about 5 PM IST on 12th April 2019, Friday to all 53000+ members. It is okay to research various online sources to learn and formulate your answer but when you submit your answer, make sure that it does not have content that is copied from elsewhere. Plagiarized answers will not be approved. (and therefore will not be displayed)  All Questions so far can be seen here - https://www.benchmarksixsigma.com/forum/lean-six-sigma-business-excellence-questions/ All rewards are mentioned here - https://www.benchmarksixsigma.com/forum/excellence-rewards/

Hi Abhay A very interesting question. I will start off by stating that there is nothing specifically known as a MBB project. Usually the projects are classified into GB or BB (in some organizations you may find a YB project as well, which basically means a small improvement project which usually does not have any tangible benefits). The difference between GB and BB projects can best be understood by evaluating the project on following parameters The above differentiation is not something cast in stone. It is only indicative. Organizations with matured lean six sigma implementation have their own criteria for decisions Hope this helps.

Hi Dipali Lean Six Sigma training is one training that will help you in topics related to project management and quality improvements. Lean Six Sigma is independent of industry i.e. its tools and techniques can be applied in any industry (including plastics) for reducing defects. Hope this helps.

Hi Rowena Gage R&R is a tool used whenever the metric is continuous and this tool helps in determining the extent of measurement system variation in the overall observed variation. Typically the survey responses are not continuous. And, it will be difficult to check for repeatability and reproducibility in a survey response as we do not expect the same response from all customers. Generally, there are other methods to check for the correctness of the survey questions like the questions should not be leading, the questions should be relevant to the product / service being offered etc. Thank you

Hi Rahul Both HR and FCR could be CTQs. Project should be picked on the CTQ that is not meeting the target value. You could start the project on HR. And if FCR is an input to HR calculation, then you will have to improve FCR as well (as a part of the project) Hope this helps.

Prashanth has defined the EFQM business excellence model before comparing the RADAR cycle with DMAIC. And he ends it with a critical evaluation of its limitations as well, there by making it the best answer.