Different number of nodes (schools) in OSM data in shp- and pbf-fomat

Dear OSM-experts,

I am quite new to OSM, and trying to use its data for my research topic.
First of all: thanks for making this possible!

I just stumble over an issue, which I cannot explain myself:

I downloaded the osm data for the Karlsruhe district (Regierungsbezirk Karlsruhe, NUTS2) at Geofabrik in .shp.zip and .osm.pbf format.

When I unpacked the .shp.zip-file and opened the file gis_osm_buildings_a_free_1.shp in arcMaps. Filtering for schools in the attribute table I found 1450 polygons.

After filtering the .osm.pbf.file for schools with Osmosis (osmosis --rbf karlsruhe-regbez-latest.osm.pbf --nkv keyValueList=“amenity.school” --wx schools.osm), I opened the resulting file in JOSM. The file contained only 301 nodes and a school in my neighborhood, which is included in the shp ist oviously missing.

Can somebody explain, where this discrepancx might come from?


Schools can be represented as points (nodes) or polygons (closed ways or multipolygon relations). It looks like your Osmosis command only considers nodes.