TY - JOUR AU - Durlauf,Steven N. AU - Hall,Robert E. TI - Bounds on the Variances of Specification Errors in Models with Expectations JF - National Bureau of Economic Research Working Paper Series VL - No. 2936 PY - 1989 Y2 - April 1989 UR - http://www.nber.org/papers/w2936 L1 - http://www.nber.org/papers/w2936.pdf N1 - Author contact info: Steven N. Durlauf Department of Economics University of Wisconsin 1180 Observatory Drive Madison, WI 53706-1393 Tel: 608/263-3859 Fax: 608/262-2033 E-Mail: sdurlauf@ssc.wisc.edu Robert E. Hall Hoover Institution Stanford University Stanford, CA 94305-6010 Tel: 650/723-2215 E-Mail: rehall@gmail.com M2 - featured in NBER digest on 1988-10-01 AB - Under rather general conditions, observed covariances place a useful lower bound on the variance of the misspecification or noise III models based on expectations. Such models are widely used for securities prices, exchange rates, consumption, and output. For a correctly specified model, the lower bound will be zero. We construct an optimal bound on model noise that captures the complete set of testable restrictions on an expectations based model. Many specification tests for asset prices are easily interpreted as estimates of this lower bound. As a result, the power of different tests may be ranked according to the information restrictions employed in constructing noise estimates. Our results show that specification tests which use the history of lagged dependent variables are usually better able to uncover model noise than based on information sets that exclude those variables. ER -