Which reputation events are private?

Question

I've been reading the API documentation on retrieving a user's reputation history ^{(docs/types/reputation-history)}
and Stack Overflow's description of how reputation is calculated.

But, I can't find the current policy on which reputation events are public versus private.
Is there a page that describes the current policy and/or which reputation events are private?

Answer 1

There doesn't seem to be a place that describes the policy. That API-object, documentation page would be perfect for it.

However, a lead Stack Exchange developer has stated that anything that reveals voting patterns will be hidden or private.

Another Stack Exchange employee explains how user deletions and post deletions are kept private-ish, but experimental observation shows that this may not carry over into what the API treats as private. (post_deleted is private, while user_deleted is public, for example.)

Here are the reputation event types and their private (need to be authenticated and visible only to the user in question) status, as experimentally determined:

Reputation History Type             Public/Private?
--------------------------------    ---------------
answer_accepted                     public
answer_unaccepted                   public
arbitrary_reputation_change         public**
asker_accepts_answer                public
asker_unaccept_answer               public
association_bonus                   public
bounty_cancelled                    probably public?
bounty_earned                       public
bounty_given                        public
post_deleted                        private
post_downvoted                      public
post_flagged_as_offensive           probably private?
post_flagged_as_spam                probably private?
post_migrated                       probably private?
post_undeleted                      does not appear?***
post_undownvoted                    public
post_unupvoted                      public
post_upvoted                        public
suggested_edit_approval_received    public
user_deleted                        public
vote_fraud_reversal                 probably private?
voter_downvotes                     private
voter_undownvotes                   private

Notes:

• ** In at least one case, anyway -- the special private beta bonus for this site.
• *** Looked in a couple of cases where rep changed due to undeletion, but this event did not appear in either the public or private API routes.
• The events with (?) could not be found by me. I don't recommend attempting spam or vote fraud to test those, either. ;)