Reliability‐Relevance Trade‐Offs and the Efficiency of Aggregation

This paper studies how an accountant's method of aggregating information in a financial report is affected by differences in the reliability and relevance of components of the report. We study a firm that hires an accountant to produce a report that reveals information to investors regarding the returns to the firm's past investments. In constructing the report, the accountant must combine information elicited from the firm's manager with other information directly observable to the accountant. The manager's information is assumed to be directly observable only by the manager and to be of superior quality to the other information available to the accountant. Reliability‐relevance trade‐offs arise because as the accountant places more weight on the manager's report, potentially more useful information gets included in the report, at the cost of encouraging the manager to distort his or her information to a greater extent. Capital market participants anticipate this behavior and price the firm accordingly. We show how the market's price response to the release of the firm's aggregate report, the efficiency of the firm's investment decisions, and the manager's incentives to manipulate the soft information under his or her control are all affected by—and affect—the aggregation procedure the accountant adopts. In addition, we identify a broad range of circumstances under which aggregated reports are strictly more efficient than disaggregated reports because aggregation tempers the manager's misreporting incentives. We also demonstrate that, as any given component of the aggregated accounting report becomes softer, the equilibrium level of the firm's investment diminishes and the market places greater weight on the remaining components of the report.