I want to create a control chart of a concentration versus time. This works well when I don't fill in the X-axis however when moving a time variable in h:min:sec to the X area the chart changes dramatically, why is this? How to solve? Thanks
The problem is that the subgroup values are not unique. JMP finds at least one subgroup that has more than 1 observation. JMP therefore switches to an XBar chart. Control Chart Builder has no way to switch from an XBar chart to an XMR chart. The legacy control charts have this functionality. You should switch to Analyze->Quality and Process->Legacy Control Charts->IR.
It sees that the time is based upon seconds, and it will change the increment. Try changing the date time variable to nominal or ordinal, and see if that solves your issue.
I tried to change to ordinal, nominal.. does not work.
Below a fragment of my data set, I would like the Time of day on X-axis.
For "Time of Day" column info is as follows: switching to continous or nominal does not work
Below is the result I get, what is wrong?
This is the required IMR chart with day as phase but with X-axis "Time of day" instead of subgroup
The problem is that the subgroup values are not unique. JMP finds at least one subgroup that has more than 1 observation. JMP therefore switches to an XBar chart. Control Chart Builder has no way to switch from an XBar chart to an XMR chart. The legacy control charts have this functionality. You should switch to Analyze->Quality and Process->Legacy Control Charts->IR.
Hello Tonya, for each of the five days there is an unique process mesurement at each Time of day going from 8:00 in the morning to midnight, so when using day as phase I woud expect an ImR chart?
Small correction above, there are 4 days (day = ordinal) labeled 2 to 5.
Problem is solved, there was one time of day too much for 5th day and so yes no unique figure for that moment, x-axis setup is of critical imortance, thanks everyone!