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A method based on an emulsification process was developed for the production of calcium alginate microspheres. Isopropyl alcohol and acetone, which are strong dehydrating agents, were used to aid in the hardening and drying of the microspheres. However, the amount of drug encapsulated was very low. This was due to the drug being soluble in the dehydrating solvents. In the absence of the solvents a high percentage of drug was encapsulated, and this was further increased by forming the microspheres by phase inversion. It was also found that a suspension of the drug particles was required for effective microencapsulation. The efficiency of drug encapsulation generally increased with the ratio of drug to encapsulating material. The microspheres produced were free-flowing and most of them were smaller than 150 microns.

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This paper describes a theory of the variability of risky choice that describes empirical properties of choice data, including sequential effects and systematic violations of response independence. The Markov True and Error (MARTER) model represents the formation and fluctuation of true preferences produced by stochastic variation of parameters over time, which produces changing true preference patterns. This model includes a probabilistic association between true preferences and overt responses due to random error. Computer programs have been developed to simulate data according to this model, to fit data to the TE model, and to test and analyze violations of iid (independent and identical distributions) that are predicted by the model. Data simulated from MARTER models show properties that are characteristic of real data, including violations of iid similar to those observed in previous empirical research. This paper also illustrates how methods based on analysis of binary response proportions do not and in many cases cannot correctly diagnose what model was used to generate the data. The MARTER model is extremely general and neutral with respect to models of risky decision making. For example, the transitive transfer of attention exchange (TAX) model and intransitive Lexicographic Semiorder (LS) models can both be represented as special cases of MARTER, and they can be tested against each other, even when binary choice proportions cannot discriminate which model was used to simulate the data. Software to simulate data according to this model, and to fit data to this model, to test this model, and to compare special case theories are included or linked to this article.