Physics

We first look for the same subject code (or exact subject name), qualification, country, currency, source release and earnings horizon. Peer institutions are matched using admissions selectivity, completion rates, undergraduate size and institution type, with a small preference for the same region. These are institutional proxies, not a ranking of programme quality.

If subject-matched peers are sparse, we try related subjects at closely matched universities, related degrees at this university, then an explicitly labelled national reference. We never multiply a salary by a university prestige score.

Peer and national estimates give each reporting institution one vote, after taking the median of its related programmes. Shared branch-campus outcomes count once. The middle-half range describes variation between reporting institutions. It is not an individual salary range or a statistical confidence interval.

Evidence labels describe match quality and coverage, not validated prediction accuracy. Admissions and size are undergraduate institutional measures, so graduate-degree comparisons are especially approximate.