User blog comment:Eles99/Study of Shelling Critical Hit/@comment-24430017-20140508190703/@comment-24782822-20140509201217

I found an official announcement about accuracy…

●魚雷命中率の向上 →全艦種の昼間魚雷命中率がupしました. 　※雷撃可能艦種全てに適用されます. 　※雷装合計値&艦娘Lv.に依存します.

・Increase of accuracy in torpedo attacks

→All sort of (friend) ships gain higher hit chance in torpedo attack in day combats.

※This is applied to all the ships that can do torpedo attack.

※Hit chance depends on ships' torp stat and their level.

（| No.112）

This information refers only to torpedo attack, but it is probably the same for shelling.