Exercise 4 results


General

Although there was not much training upfront, you did exceptionally well! Most of you delivered at least meaningful data, and all of you invested time and showed engagement. I also thank you for typing in the data since this simplified the evaluation very much.

Since it was quite some work, the delivery of any results is giving you 15 points, and the correctness of the results another 15 points. The correctness was calculated through a 1/(1+RMS) (root mean square) function of the relative errors of all the figures you entered. The function yields 1 for perfect agreement and 0 for no agreement. My congratulations go to Tim for achieving the best result.

Some of the minor errors might be my fault since I gave you a wrong function for the calculation of the precision: The precision is the standard deviation of the values divided by the average of the value (and not by the theoretical value as I stated). One of you noticed it and asked, but that was already after the lecture and I did not want to spam you for that since the errors should not be too relevant. Please accept my apologies.. the instructions were not well structured.

The complete result evaluation is available for download under Exercises – Exercise 4 – Exercise 4 results.xlsx. It’s sorted by data set and my values are in the rows underlied with grey.

  1. Exercise 4 results – all your data, my data, and point calculation
  2. Data set.. – all three data sets
  3. Weighted… – all the calibration files
  4. Data evaluation – my proposal how to calculate the A&P values for all three data sets

Observations

One of you (matrikel -500) delivered perfect values except at the end, it looks as if the values had been typed first and then copy/pasted from Excel – please be aware that if you have an excel cell containing percentage calculation like =STDEV(…)/AVG(…) and format it as percentage, the cell shows e.g. 15%, but the cell value if you copy is 0.15!

The next lesson is on HPLC basics and how theoretically a method is developed. The exercise will be conventional and hopefully less time consuming.

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