Stats - coverage Chart

The chart shows my best coverage as ESE which in actual fact is my worst direction. My best is WSW.

rustytwig

Is your position correct on your map of feeder site ?

The “Coverage Distribution” is a very good idea.
Nevertheless, the pop-up text shows “200+ NM” for all the color segments, so we don’t really know the scale. (it would be nice for the scale to be in km too… :laughing: )

Same in my case, the direction is wrong.

Mine is 180° out, will be a great feature though.

I think the scale is proportional to the number of reports sent not the distance.

The different colors seem to be the different “histogram classes”, each for a distance range, the size of the segment being the number of reports. No ?

You’re correct. We’ll be rolling out an update today that clarifies the labels and shows the exact distance ranges. The ranges are 0-50, 50-100, 100-150, 150-200, and 200+ nm, and the segments represent the number of aircraft seen in that distance range in that direction over the last day.

We’re working on improving the accuracy of the directions reported. We’ll also be rolling out even more stats today and in the coming few weeks. We appreciate all the feedback, and it will be very helpful in pinpointing and fixing any inaccuracies.

I agree with the other users, something is wrong in the positioning.

This

http://i.imgur.com/SMAwSuQ.png

is not like that

http://i.imgur.com/DA1Srb7.png

My coverage after ~12 hours of data collecting (it won’t change significantly if I run it over a longer period) (range rings every 25NM)
http://s11.postimg.org/jv3tzj1sz/Picture_10.png

http://s11.postimg.org/cgei75fxf/Picture_11.png

Liviu

Hello all

I like the idea of this chart.

We do need a definition of what the different colors mean. I do see where the outline of this chart will not look like a range chart. This chart is quantity of reports where a distance chart could be made up primarily of single plane detections that wouldn’t necessarily show in this chart.

If the color is for quantity of reports, I feel each zone of the chart, sixteen directions times five or more distances, should get its appropriate color. As an example, someone who has primarily traffic at a distance would show the higher traffic color indication in the appropriate 16x5 areas of the chart with the color for lower numbers close to the center. In my current chart, I see one direction with a green wedge extending four and one-half rings. I don’t know if this means all those areas had about the same quantity of reports or just the farthest area.

Gary

Also the direction of the most positions is not necessarily the direction of the greatest range. I know topography plays a large part but I have a theory that if there is a greater density of aircraft your range is shortened due to the high noise level of closer aircraft transmissions. This is demonstrated at my location here in Wales where I can receive aircraft at 212nm in the South West where there is low density of traffic and only 50nm in the South East where a large volume of traffic is approaching westbound from London.

And perhaps planes do not move in all directions : In my location, they pass at my W and E, coming from and going to Paris but not at my south.

Aloha,

I must have missed something, would somebody reply with “how to view the coverage chart for my site?”

Thanks

The graph is no more available for now.

Hi,

Is the “number of aircraft seen” based upon the count of different ICAO plane numbers or the count of different registration numbers ? In the first case, the count is lower because the same plane is often used 2 times a day for inbound and outbound flights. In the second case, it seems “better”.

Another question / clarification :

My understanding of the stats page is that

a) The aircraft seen daily average is calculated from the data of the previous 30 days and does not change during the current day.

b) The aircaft seen total however seems to be calculated differently.
At switchover (1am CET) the total from the 31st day is deleted and during the current day the total is adjusted at each refresh.
(My observation is that at 1am the total value drops and then increases again during the day)

Is ths correct ?
Mezoo

Yep.

It was probably explained somewhere - but I can’t find it anymore.

Why is there a difference in the number of aircraft seen between the table and the daily collection graph ?
Usually in my stats the graph shows about 10% less for a any given day.

Hi mezoo, could you clarify the discrepancy you’re noticing? I’ve checked your stats page and the daily collection graphs seem to correspond with the numbers in the table for you. For instance, both the first graph and the table show 2917 aircraft seen on the 13th.

Note that the graph does linearly interpolate between data points, so your cursor has to be precisely lined up with a specific day in order for the number to match exactly what’s in the table. It can be quite sensitive and this may explain the confusion.

OK, that could explain the difference.

But then I think the interpolation is a bit conusing as it produces no useful data.
Instead I would propose just to have the numbers for the individual days.

mezoo