正解: BCorrect: B
相関は因果を意味せず、意欲や能力といった交絡因子が研修時間と昇進の両方を生んでいる可能性をまず検討すべきです。Correlation does not imply causation; first consider confounders such as motivation or ability that could drive both training hours and promotion.
相関関係が観察されたとき、考えられる説明は少なくとも四つあります。研修が昇進を促す（想定した因果）、昇進候補者だから研修を受けさせられている（逆の因果）、意欲や能力が両方を生む（交絡）、そして偶然です。本問では、意欲の高い社員が自ら研修を選び、かつ成果を上げて昇進するという交絡が最も自然な代替説明です。選択肢Aは相関の強さと因果を混同しています。Cはサンプルを増やしても交絡は消えません。Dは自己申告で、成功した人が事後的に理由を見出す傾向があるため因果の証拠にはなりません。因果を確かめるには、研修をランダムに割り当てる実験や、同等の意欲を持つ社員同士を比較する準実験的な手法が必要です。When a correlation is observed, at least four explanations are possible: training drives promotion (the assumed causation), promotion candidates are sent to training (reverse causation), motivation or ability drives both (confounding), and chance. Here the most natural alternative is confounding: motivated employees choose more training and also perform well enough to be promoted. Option A confuses correlation strength with causation. Option C ignores that a larger sample does not remove confounding. Option D relies on self-reports, and successful people tend to construct reasons after the fact. Establishing causation requires randomized assignment of training or quasi-experimental methods that compare employees with similar motivation.
現実の組織では研修をランダムに割り当てる実験は倫理的・実務的に難しく、観察データから因果を推定するには高度な手法と前提が必要です。また分析結果を待つ間に意思決定が先送りされ、「何もしない」という選択が暗黙のうちに採用されてしまうこともあります。Randomly assigning training in a real organization is often ethically and practically difficult, and inferring causation from observational data requires sophisticated methods and assumptions. Waiting for rigorous analysis can also delay decisions so long that 'do nothing' becomes the default choice, and HR leaders may feel the correlation is evidence enough.
全社義務化の前に、一部の部署や新入社員層で段階的に導入し、導入群と未導入群の昇進率や評価の変化を比較する準実験を行います。さらに研修の内容と昇進要件の関連を定性的に確認し、因果のメカニズムが説明できるかも検証します。Before a company-wide mandate, roll training out in stages to selected departments or new-hire cohorts and compare promotion and evaluation changes between participating and non-participating groups. Also examine qualitatively whether the training content connects to promotion criteria, so that a plausible causal mechanism can be articulated. Set a decision date in advance so analysis informs rather than replaces the choice.