Methodology

01 / Minimum-weight overlap

Weighted overlap is the sum of min(weight in fund A, weight in fund B) for each matching security identifier. Inputs are percentage weights, not share counts.

02 / Your allocation and combined exposure

Combined portfolio exposure is allocation A × holding weight A plus allocation B × holding weight B. The two allocation percentages sum to 100%.

03 / Incomplete holdings coverage

Partial holdings files remain partial. The model never rescales a top-ten list to look like a complete fund. The unreported portion is labeled unreported, not cash.

04 / Snapshot dates and identifiers

Provide one snapshot date per fund and one row per security identifier. Different dates across funds are shown visibly. Normalize identifiers before importing; reused tickers or share classes need careful reconciliation.

05 / Sector classifications and model limits

This version supports unlevered long-only weights. It rejects negative weights and fund totals above 100.05%. Derivatives, look-through fund-of-funds exposure, and shorts require a richer model.

Handling invalid and missing inputs

Unsupported or invalid inputs stop the calculation instead of producing a plausible-looking fallback. Missing borrow fees, missing returns, missing dates, and unavailable cutoffs are retained as missing or unavailable rather than replaced with zero. CSV imports are checked for required columns, duplicate records, date formats, and domain-specific consistency.

Sources