Image theory has been proposed as a descriptive model of decision making. The present work examines the sufficiency of a simple counting rule as a theoretical description of the assessment of compatibility, a central construct in the theory. The research was done in the context of executives assessing the compatibility between plans for reaching a specified goal and the principles that guide the operation of their respective firms. First, for each firm an expert‐system simulation was performed using Image Theory as the ‘expert’, the firm's guiding principles as the criteria, and the counting rule as the assessment procedure. This yielded a simulated compatibility assessment for each plan for each firm. Executives from each firm also assessed the compatibility of each plan with their own firm's operating principles. The assessments from the simulation were then compared with those made by the executives. The results support the descriptive sufficiency of the simple counting rule and recommend its tentative incorporation into image theory.

Aims:  A series of experiments were conducted to evaluate the effect of surface charge and air ionization on the deposition of airborne bacteria. Methods and Results:  The interaction between surface electrostatic potential and the deposition of airborne bacteria in an indoor environment was investigated using settle plates charged with electric potentials of 0, ±2·5kV and ±5kV. Results showed that bacterial deposition on the plates increased proportionally with increased potential to over twice the gravitational sedimentation rate at +5kV. Experiments were repeated under similar conditions in the presence of either negative or bipolar air ionization. Bipolar air ionization resulted in reduction of bacterial deposition onto the charged surfaces to levels nearly equal to gravitational sedimentation. In contrast, diffusion charging appears to have occurred during negative air ionization, resulting in an even greater deposition onto the oppositely charged surface than observed without ionization. Conclusions:  Static charges on fomitic surfaces may attract bacteria resulting in deposition in excess of that expected by gravitational sedimentation or simple diffusion. Implementation of bipolar ionization may result in reduction of bacterial deposition. Significance and Impact of Study:  Fomitic surfaces are important vehicles for the transmission of infectious organisms. This study has demonstrated a simple strategy for minimizing charge related deposition of bacteria on surfaces.