Control over grain size in memory reporting--with and without satisfying knowledge.

When answering questions from memory, respondents strategically control the precision or coarseness of their answers. This grain control process is guided by 2 countervailing aims: to be informative and to be correct. Previously, M. Goldsmith, A. Koriat, and A. Weinberg Eliezer (2002) proposed a satisfying model in which respondents provide the most precise answer that passes a minimum-confidence report criterion. Pointing to social-pragmatic considerations, the present research shows the need to incorporate a minimum-informativeness criterion as well. Unlike its predecessor, the revised, "dual-criterion" model implies a distinction between 2 theoretical knowledge states: Under moderate-to-high levels of satisfying knowledge, a grain size can be found that jointly satisfies both criteria--confidence and informativeness. In contrast, under lower levels of unsatisfying knowledge, the 2 criteria conflict--one cannot be satisfied without violating the other. In support of the model, respondents often violated the confidence criterion in deference to the informativeness criterion, particularly when answering under low knowledge, despite having full control over grain size. Results also suggest a key role for the "don't know" response which, when available, can be used preferentially to circumvent the criterion conflict.