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I__. - International Military Testing Association

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In attempting to relate ASP score to demographic characteristics, an ordinary least squares regression was run.<br />

The results yielded an ti =.213 and a root mean square error of 9.198. The large standard error is providing the<br />

motivation to determine whether these results can be improved upon using a neural network approach that attempts<br />

to map responses as opposed to total scores.<br />

Neural Network Approach to Distortion Detection<br />

The network paradigm that is currently being investigated is the cumulative backward error propagation<br />

network. The network has fifty outputs representing individual responses. The hidden layer includes 120 ncurodes<br />

and each uses a hyperbolic transfer function. The inputs include the same demographic information that was<br />

hypothesized to be related to the ASP score in the earlier regressions. The network is shown graphically in Figure<br />

2.<br />

:umulativs Backward Error-Prnpagatton Network<br />

Figure 2. Response Pattern Distortion Detection Network.<br />

Due to the number of calculations that are involved in training the above network to recognize response pattern<br />

distortion, a mainframe version of the cumulative backward error propagation neural network has been written for<br />

the IBM 4381 and implemented at the Navy Personnel Research Development Center (NPRDC). The current<br />

implementation is written in FORTRAN 77. Other network paradigms such as Grossberg’s Outstar , counter<br />

propagation, and others are in the process of being added. Although, results arc extremely encouraging, it is<br />

premature to report them at this time.<br />

Summary<br />

CertainIy neural network technology is still in its youth, nevertheless it has experienced significant growth in<br />

recent years and the momentum shows no signs of slowing. Initially, the technology had a “black box” image, but<br />

recent articles such as those by Ho&c and Funahashi demonstrate that neural networks is well founded in<br />

mathematical theory and has statistical roots. That is to say, that a simple ordinary lcast squares regression can bc<br />

expressed as a neural network, albeit a simple one. Neural networks have the potential for providing unique<br />

approaches and insights into, heretofore, intractable problems. In the context of military manpower research, the<br />

jury isn’t still deliberating, because all the evidence has not yet been presented. But when it is, we may find WC<br />

have new answers to old problems.<br />

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