On 14/03/2016 03:03, Tomaz Canabrava wrote:
All, Davide:
This is by no means finished,
Davide, I'm using your wireframe ideas on filtering, this screenshoot
uses fake data just to make it easier to present.
What kind of graph you guys thinks it's the best?
Tomaz,
You are doing amazing stuff. Three suggestions on the statistics:
1) If only minimum, mean and average are plotted, then the statistically
correct way to plot is by using three lines on the graph. A bar chart is
inappropriate. With a bar chart, the vertical distance below the curve
is meant to have content which it does not have in the present case. If
one wanted to plot, for instance, "no. of dives with sac below 15", "no.
of dives with sac between 15-15", "no. dives with sac above 25", then a
bar chart would be appropriate. I include a mockup I made in R of what
the appropriate chart should look like if one were to be statistically
correct, using your min, mean and max.
2) The term "Average" is statistically undefined. It can imply any of
several interpretations. E.g if I took 6 hours to drive the 300 miles
from San Francisco to Los Angeles, the average speed would be 300/6 = 50
mph. However, if I measured my speed at 10 fixed points along the
route, I am able to calculate (sum of all speeds)/10 = mean speed. The
appropriate term in our case is therefore "Mean".
3) In these graphs, the vertical axes need to be associated with a
specific measurement unit (e.g. SAC (litres/min)). This brings up the
issue of SI and imperial units.
Kind regards,
willem
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