Forum Discussion
finding deviations from the mean
Valentinaampuero So I go the sample files (May-Nov of 2021). I am attaching the Nov data here. In this file I added a tab (DailyAvg) where I calculate the average for every :15 sec slot for each panel across all the days recorded. I then calculate the average (col LED) and std (col LEE) for each :15sec slot and added conditional formatting to highlight all the spots <1std (orange) and <2 std (red). Finally at the bottom I did a count for how many times that particular panel was found to be <1 STD and <2 STD on average. I hope this might be helpful and can be a template for the other months. Maybe even collate these summary counts across months for even better indicator of performance across the year.
Valentinaampuero So I go the sample files (May-Nov of 2021). I am attaching the Nov data here. In this file I added a tab (DailyAvg) where I calculate the average for every :15 sec slot for each panel across all the days recorded. I then calculate the average (col LED) and std (col LEE) for each :15sec slot and added conditional formatting to highlight all the spots <1std (orange) and <2 std (red). Finally at the bottom I did a count for how many times that particular panel was found to be <1 STD and <2 STD on average. I hope this might be helpful and can be a template for the other months. Maybe even collate these summary counts across months for even better indicator of performance across the year.
mtarler Wow! you did in one hour what i couldn't do in the whole weekend hahaha
I'm looking at the file right now and trying to understand the formulas and the results.
Thank you so much!
Valentinaampuero please see my reply below to @mtarler
- Hello, thanks for your answer. Now, if i have understood correctly the Standard deviation is not a valid measure because the data does not behave normally.
Maybe the way you propose is more accurate and it should be used.
ThanksValentinaampuero That is correct. And, if I understand correctly that this data is related to solar power capture, then all of the 0's before 7:00am in the morning in your dataset are also irrelevant: since, it simply makes sense that you will not capture solar energy when it is dark outside. Even still, without the impact of these 0's, yes, my median approach is more stable and does not rely on normality. Hope this helps.
