Evaluating a new computer-based system for face recall

The Computer-Aided Design Centre has developed a new face recall system which enables a witness to construct the image of a suspect on a television screen. The system currently uses the Photofit library and method of construction. Likenesses of target faces produced by subjects (n=36) using the new system were compared to conventional Photofits produced by a second group of subjects (n=36) of the same targets. There was no difference on any of the three measures employed in the assessed quality of the likenesses produced by Photofit and the CADC System. Both systems tended to produce more recognizable composites when construction was carried out in the presence of the target compared to its absence. Composites made from memory on the initial trial were marginally better with the CADC System than with Photofit. While both systems showed low absolute accuracy, they enjoyed a measure of success in transmitting a likeness of a facial type. It is concluded that while the CADC system shows promise, psychological constraints upon witnesses' powers of recall may place limits on the absolute accuracy achievable with any system of face reconstruction.These experiments were financed by grant No. POL/73 1675/24/3 from the Police Scientific Development Branch of the U.K. Home Office. Points of view expressed in this article are solely those of the authors and do not necessarily reflect the opinions or positions of the funding body. Our gratitude and thanks are due to Tony Kitson and Clive Holloway for their many hours spent developing and operating the CADC system; Jean Shepherd for her skills as a Photofit operator; the Computer-Aided Design Centre; and the MRC Applied Psychology Unit, Cambridge for facilities and subjects.     

Diffusion milieus as a focus of research on innovation in the public sector

Public policies to increase the efficiency of state and local governments through fostering the use of new technologies are based, implicitly at least, on theories of diffusion. Existing theories of diffusion have been found to be deficient. This paper presents an approach to the diffusion of technological innovations in state and local governments organized around the concept of diffusion milieus.A diffusion milieu contains those elements external to the organization which bring pressure to bear on the organization to alter its existing practices, which define the range of feasible alternatives to these practices, and which condition the information flow on the performance characteristics of the proposed innovation(s). These milieu components are then filtered through the internal decision-making process(es) of the organization to produce a decision to accept or reject the innovation(s). More specifically, the milieu contains (1) the specific nature of the demands upon the agency to change behavior (performance gaps), (2) the supply of alternatives to existing practices (technological change), (3) agency-executive relationships, (4) the activities of suppliers in marketing innovations, (5) the resources available to the agency to acquire new techniques, (6) the characteristics of the knowledge infrastructure which affect the search behavior and the degree of uncertainty associated with adopting new techniques, (7) the impact of intergovernmental relationships, and (8) citizen demands. The components of the diffusion milieu are then (9) related to a set of agency decision-rules concerning the adoption of new techniques.The rate of diffusion in each field will depend upon themagnitude of the components and on thelinkages between them.Functional fields differ in both respects.Research for this paper was supported by a grant from the National Science Foundation, Office of R & D Assessment. We have benefited from the helpful comments of Professor Marvin Rozen, an anonymous referee and the research assistance of Ms. Lee Ann Kozak. The views expressed in this paper are the sole responsibility of the authors. An earlier version of this paper was presented at the 1975 American Political Science Association meetings.