heuristics and of the biases to which they lead could improve judgments and
decisions in situations of uncertainty.
Acknowledgments
This research was supported by the Advanced Research Projects Agency of the Department of De-
fense and was monitored by the Office of Naval Research under contract N00014-73-C-0438 to the
Oregon Research Institute ,Eugene. Additional Support for this research was provided by the Re-
search and Development Authority of the Hebrew University ,Jerusalem ,Israel.
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