I am looking for statistics (raw data) on the most common readings for kanji
used in names (family name or first name) and the most common gender for a
name. Existing dictionaries tend to just spit out all possible readings for a
name even when only 1 or 2 are likely; I'd like to improve that.

There are loads of websites that offer this on a per-lookup basis, e.g.
<https://namegen.jp/yomikata> - so the raw data must be out there. I checked
Census data but could not find it. I googled for research papers and visited
websites. <http://www.myj7000.jp-biz.net/1000/0100f.htm> looked promising, but
is broken? Or I can't figure out how to use it.

I have searched for combinations like 名字調査 統計 データ etc. but to no avail. Would
really appreciate any help.

I also considered crawling wikipedia, which would work (if I can figure out
how to remove fictional characters) but won't be as granular or accurate as
the data these other sites are using.
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2019-06-26T22:25:02.490
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question
names gender statistics
Statistics on common readings for Japanese names
The website you gave gives stats:

example for 雅

<https://namegen.jp/yomikata?name=%E9%9B%85>

This looks like exactly what you want
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2019-06-27T00:17:38.767
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answer