Can you make a run chart in minitab express

CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS PDF
CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS SOFTWARE
CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS SERIES
CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS DOWNLOAD

We went through a process capability checklist designed to help you paint a true picture of your process capability вЂ“ to increase the confidence you, your leadership, and your customers have in your process capability. Last monthвЂ™s publication was entitled вЂњ Cpk Alone is Not Sufficient.вЂќ In that publication we took a look at the why a Cpk value by itself is not sufficient to describe the process capability. If you are new to process capability, please take a moment to review that publication. In addition, the workbook showed how Cp, Cpk, the sigma level, and the ppm out of specification changed as the average and standard deviation changed. You were able to see visually how the process shifts versus your specifications.

CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS DOWNLOAD

You could download an Excel workbook that let you visually see how changing the average and standard deviation of your process impacts your process capability. We reviewed the process capability calculations, including Cp and Cpk. Two months ago, we took an interactive look at process capability.

CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS SERIES

This is the third in a series of SPC Knowledge Base publications on process capability.

CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS PDF

You may download a pdf copy of this publication a t this link. What are they? What are they measuring? What do the values means? Which one should you rely on? Some of the answers may well surprise you. In this monthвЂ™s SPC Knowledge Base publication we take an in-depth look at Cpk and Ppk. But, far too often, we simply take the results and move forward without thinking about what they mean. Software today makes it easy to plug the data in and generate the results. Know what it is?Д¬pk and Ppk are two commonly used measures of process capability вЂ“ how well your process is meeting your customer specifications. You just missed a very important piece of information about your supplierвЂ™s performance. The Cpk is above 1.33, which is what you asked the supplier for. Why are those different? Well, it doesnвЂ™t matter. You note one capability chart that has a Ppk = 1.14 and a Cpk = 2.07. Looks like your supplier is really performing for you. You know, things like Cpk, Ppk, sigma level, ppm out of spec and so on.

CAN YOU MAKE A RUN CHART IN MINITAB EXPRESS SOFTWARE

The supplier has produced some very nice charts, obviously generated with some fancy software package вЂ“ and, of course, with all those accompanying statistics. In a mixture pattern, the points tend to fall away from the center line and instead fall near the control limits.Your supplier has sent you the process capability charts you requested. Test 8: Eight points in a row more than 1Пѓ from center line (either side) Test 8 detects a mixture pattern. Control limits that are too wide are often caused by stratified data, which occur when a systematic source of variation is present within each subgroup. This test detects control limits that are too wide. Test 7: Fifteen points in a row within 1Пѓ of center line (either side) Test 7 detects a pattern of variation that is sometimes mistaken as evidence of good control. Test 6: Four out of five points more than 1Пѓ from center line (same side) Test 6 detects small shifts in the process. Test 5: Two out of three points more than 2Пѓ from the center line (same side) Test 5 detects small shifts in the process. You want the pattern of variation in a process to be random, but a point that fails Test 4 might indicate that the pattern of variation is predictable. Test 4: Fourteen points in a row, alternating up and down Test 4 detects systematic variation. This test looks for a long series of consecutive points that consistently increase in value or decrease in value. Test 3: Six points in a row, all increasing or all decreasing Test 3 detects trends. If small shifts in the process are of interest, you can use Test 2 to supplement Test 1 in order to create a control chart that has greater sensitivity. Test 2: Nine points in a row on the same side of the center line Test 2 identifies shifts in the process centering or variation. Test 1 is universally recognized as necessary for detecting out-of-control situations. Test 1: One point more than 3Пѓ from center line Test 1 identifies subgroups that are unusual compared to other subgroups. Only Tests 1в€’4 apply to the R chart portion of this control chart. Eight tests are available with this control chart. Test 2 detects a possible shift in the process. For example, Test 1 detects a single out-of-control point. Each of the tests for special causes detects a specific pattern or trend in your data, which reveals a different aspect of process instability. Use the tests for special causes to determine which observations you may need to investigate and to identify specific patterns and trends in your data.

Can you make a run chart in minitab express