What's confusing you exactly?
FYI this is from the maker of this completely meaningless map(
https://www.reddit.com/r/dataisbeau...fo_sightings_in_the_netherlands_1994_2016_oc/) :
"Someone (I believe it was this subreddit) posted a link to
this website , and I just spent a saturday morning making this map in Illustrator. For fun, not science.
Edit: Yeah, if everyone could stop acting as if this is some hermetic scientific/statistical statement, that'd be great.
The data are from some bullshit website gathering bullshit reports on bullshit ufo sightings, ffs. I just had some fun making a map, and some of you are taking this way too serious. Lighten up and simmer down people."