On previous versions of the server, if the result set is empty from a geoNear command, avgDistance was NaN. The following is using 3.0.7:
{ "results" : [ ], "stats" : { "nscanned" : 12, "objectsLoaded" : 4, "avgDistance" : NaN, "maxDistance" : 0, "time" : 0 }, "ok" : 1 }
On 3.2.0-rc0, avgDistance is missing:
{ "waitedMS" : NumberLong(0), "results" : [ ], "stats" : { "nscanned" : 10, "objectsLoaded" : 4, "maxDistance" : 0, "time" : 1 }, "ok" : 1 }
It seems that this is a bug as maxDistance is included even though it's 0.