Answer product-owner round 1: a Swedish street is a street's name, Lexington, Ventura and Lynchburg ship by their postal names, and the README names Honolulu

data-import/geo-se.py

@@ -38,6 +38,10 @@ TIMEZONE = "Europe/Stockholm"
 ONE_POSITION = {"Stockholm", "Göteborg", "Malmö"}
 # A tätort's floor: "minst 200 invånare", docs/research/research-geo-se.md, Lantmäteriet → Ortnamn.
 UNMATCHED_POPULATION = 200
+# Not a street: a road number, a ferry route, a cycle path or road association's label, a placeholder, or two names
+# or a description in one.
+NOT_A_STREET = re.compile(r"^(Europaväg|Länsväg|Riksväg) \d|^Färjeled |\b(GC|SMF|VSF)\b|^NN$|, ")
+PARTICLES = {"af", "de", "von"}
 
 
 def scb_codes(cache):
@@ -161,12 +165,18 @@ def localities(codes, tatorter, municipalities, population):
     return out
 
 
+def street_name(name):
+    """Whether name is a street's, opening with a capital or a nobiliary particle and with no word spelled in capitals."""
+    opening = name[0].isupper() or name.split()[0] in PARTICLES
+    return opening and not NOT_A_STREET.search(name) and not any(len(w) >= 5 and w.isupper() for w in name.split())
+
+
 def streets(segments, codes, localities, share, minimum):
     """The names with most segments per locality, each segment at its nearest code centroid."""
     nearest = geo.Nearest((r["lat"], r["lon"], r["locality"]) for r in codes if r["lat"] is not None and r["locality"] in localities)
     count = collections.Counter()
     for name, lat, lon in segments:
-        if name[0].isalpha():
+        if street_name(name):
             count[(nearest.find(lat, lon), name)] += 1
     return geo.top_streets(count, share, minimum, "segments")