Hello, I am not particularly well versed in statistics but I am doing some research and encountered something I didn't understand and was hoping someone here could help.
For my research, we need to find the pump speed with the most consistency when filling a vial to 50ml. I am not sure if I should use the standard deviation of the time it takes to fill the 50 ml or the rate (ml/s). Now to me, it seems like there shouldn't be any difference but clearly there is. By time, Pump 8 is best and by rate Pump 6 is best.
Could anyone tell me (1) if this is a good way to find the consistency of the pump and (2) why the standard deviation of the time is different from the rate. ( I understand why the number itself is different but not why the ranking of deviation is different. )
Here is the link to the google doc. I hope this is allowed but if not I will attach the PDF. Thank you very much!
https://docs.google.com/spreadsheet...ouid=117381524468896122553&rtpof=true&sd=true
For my research, we need to find the pump speed with the most consistency when filling a vial to 50ml. I am not sure if I should use the standard deviation of the time it takes to fill the 50 ml or the rate (ml/s). Now to me, it seems like there shouldn't be any difference but clearly there is. By time, Pump 8 is best and by rate Pump 6 is best.
Could anyone tell me (1) if this is a good way to find the consistency of the pump and (2) why the standard deviation of the time is different from the rate. ( I understand why the number itself is different but not why the ranking of deviation is different. )
Here is the link to the google doc. I hope this is allowed but if not I will attach the PDF. Thank you very much!
https://docs.google.com/spreadsheet...ouid=117381524468896122553&rtpof=true&sd=true
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