Eye‐Tracking as a Measure of Responsiveness to Joint Attention in Infants at Risk for Autism

Reduced responsiveness to joint attention (RJA), as assessed by the Early Social Communication Scales (ESCS), is predictive of both subsequent language difficulties and autism diagnosis. Eye‐tracking measurement of RJA is a promising prognostic tool because it is highly precise and standardized. However, the construct validity of eye‐tracking assessments of RJA has not been established. By comparing RJA an eye‐tracking paradigm to responsiveness to joint attention during the ESCS, the current study evaluated the construct validity of an eye‐tracking assessment of RJA for 18‐month‐old infant siblings of children with autism. Relations between measures of RJA and concurrent language skills and autistic symptomatology were assessed. Correlations between measures of ESCS RJA and eye‐tracking RJA were statistically significant, but few relations between either ESCS or eye‐tracking assessments of RJA and language or symptoms were observed. This study establishes the construct validity of eye‐tracking assessments of RJA.     

Directed Matching and Monetary Exchange

We develop a model of monetary exchange where, as in the random matching literature, agents trade bilaterally and not through centralized markets. Rather than assuming they match exogenously and at random, however, we determine who meets whom as part of the equilibrium. We show how to formalize this process of directed matching in dynamic models with double coincidence problems, and present several examples and applications that illustrate how the approach can be used in monetary theory. Some of our results are similar to those in the random matching literature; others differ significantly.