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Phytoplankton Data Analysis
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BV.um3.L = -9999 for sheets 679:684 #27

Closed jbeaulie closed 10 years ago

jbeaulie commented 10 years ago

These sheets only report cells per mL, but we appear to have coded biovolume (BV.um3.L) as -9999 in the .csv file. Shouldn't this be reported as NA rather than -9999? Or did we agree to use -9999 as a flag?

Oddly, many of the observations in these sheets report a cell count of 0. There is really no need to read these into the .csv file.

mjpdenver commented 10 years ago

Does this relate to issue #3 - where no-algae found is reported.? Here we decided to record them as 0. This is an assumption that will have to be mentioned in the analysis - whether the absence of an record means a taxa was not found vs. a taxa was not sought.

Date: Tue, 22 Apr 2014 13:33:10 -0700 From: notifications@github.com To: Phytoplankton-Data-Analysis@noreply.github.com Subject: [Phytoplankton-Data-Analysis] BV.um3.L = -9999 for sheets 679:684 (#27)

These sheets only report cells per mL, but we appear to have coded biovolume (BV.um3.L) as -9999 in the .csv file. Shouldn't this be reported as NA rather than -9999? Or did we agree to use -9999 as a flag?

Oddly, many of the observations in these sheets report a cell count of 0. There is really no need to read these into the .csv file.

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jbeaulie commented 10 years ago

The dependent variable in the statistical analysis will be total blue-green algae per sample. In the case of issue #3, the taxonomist was specifically looking for blue-green algae and found none. In that case, it is appropriate to report a cell count of 0 for taxa 'NA' and class 'Blue-green'. When we aggregate the data by class, we will have a record of 0 for Blue-green algae on that lake x site x date combination.

In the current issue (#27), I have no idea why the taxonomist reported a value of 0 for some algae taxa. I very much doubt that those taxa were specifically sought out and not found. Under these conditions, I think it is best to ignore those records all together.

mjpdenver commented 10 years ago

The script is also missing from the summary page. Change made in script readEFR.R. script added to summary sheet.