An analyst is finalizing a report that discusses the effects of survivorship bias.

Survivorship bias occurs when funds that have failed, closed, merged, or otherwise ceased to exist are removed from a performance comparison universe. Because unsuccessful funds are disproportionately likely to disappear, the funds remaining in the universe tend to have better results, causing historical performance statistics to appear stronger than they actually were for the complete original population. IFC explains that defunct portfolios drop out of subsequent rankings and that these terminated portfolios are usually unsuccessful, producing an upward bias in the longer-term returns of the surviving universe. Options A through C describe mismatches between investment mandates, asset categories, or risk profiles rather than survivorship bias. Therefore, the exclusion of defunct portfolios described in option D is the defining characteristic.

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