[tor-dev] Statistics on fraction of connections used uni-/bidirectionally

[Rob Jansen]

On Dec 21, 2013, at 4:13 AM, Karsten Loesing wrote:

> On 12/18/13 2:03 PM, Rob Jansen wrote:
>> On Dec 18, 2013, at 4:51 AM, Karsten Loesing wrote:
>>> I also
>>> aggregated observations similar to Torperf measurements, by plotting
>>> only median and interquartile range.  Here's the result:
>>> 
>>> https://people.torproject.org/~karsten/volatile/connbidirect-2013-09-19-2013-12-18.png
>>> 
>>> The old graph containing the same data is still there:
>>> 
>>> https://metrics.torproject.org/performance.html?graph=connbidirect&start=2013-09-19&end=2013-12-18#connbidirect
>>> 
>>> Do you like the new graph?  Do you have further ideas for improving it?
>> 
>> I do like the new graph, its much cleaner than the old one. But I like the mostly reading/writing parts of the old one too. Maybe we can create two more graphs like the new one (1 for mostly reading and 1 for mostly writing).
> 
> Ah okay, then let's put the unidirectional parts back into the graph.  I
> made another graph with all three parts (both reading and writing,
> mostly writing, and mostly reading) displayed with medians and
> interquartile ranges on the same y axis.  I find it easier to compare
> the three parts in this graph than in three separate graphs with
> possibly different y axis scales.
> 
> https://people.torproject.org/~karsten/volatile/connbidirect-2-2013-09-19-2013-12-18.png
> 
> How's this one compared to the other two?

Awesome! This is even better than have 3 separate graphs. I think this achieves the best balance between summarizing the data and showcasing the data that is available.

> 
>> I also think a stacked percentage area graph (e.g. http://www.highcharts.com/demo/area-stacked-percent) could work here, as a way to get all the data on the same chart.
> 
> I'm not really sure how that would work with our data.  We could only
> display medians, not interquartile ranges.  And our three medians don't
> even add up to 100%; using means instead of medians might fix this,
> though I didn't check.

Ah, I see. I assumed they added to 100%.

> 
> Do you think this graph would be easier to understand than the one I
> posted above?
> 

Likely not, given the above comment. I'd say ignore this suggestion.

>>> This graph is only there to show what kind of data we have.  If somebody
>>> is really interested in the data, they'll have to download the CSV file
>>> and do their own analysis.  Here's the specification of the file format:
>>> 
>>> https://metrics.torproject.org/stats.html#connbidirect
>>> 
>>> All the best,
>>> Karsten
>>> 
>> 
>> If the main goal is to show the data that exists, I think the old graph does that fine. But I think an important subgoal is also to have graphs that make it clear how the data is useful, not only that it exists. Perhaps keep both/all versions?
> 
> Agreed, the graph should be useful, not just show that we have the data.
> Though I'd want to avoid adding a second or third graph and instead
> pick the most useful one we can come up with here.
> 
> Thanks for your input!  Much appreciated.
> 
> All the best,
> Karsten

I think your newest graph (the one with the three median+range plots on the same graph) is the best, and would be happy if we switched to that one.

Best,
Rob