To capture the risk-aversion intuition, the standard approach in economics has been to utilize the model of expected utility, in which risk aversion derives from diminishing marginal utility for wealth (or diminishing marginal utility for aggregate consumption). The expected utility model for risk aversion has been used to derive many important insights. But over the years, economists and psychologists have identified various problematic issues with expected utility as a descriptive model of choice. In this article, we urge economists to take seriously the research agenda of developing and assessing different ways to model risk aversion. We proceed in three main steps. First, we highlight that the basic intuition of risk aversion that drives many results in economics is not intimately tied to expected utility. Second, we describe a few alternative models that can also capture the basic intuition of risk aversion. Finally, we discuss that, while expected utility and the alternative models might all capture the basic intuition of risk aversion, the alternative models can generate additional, more nuanced implications not shared with expected utility, that in some cases seem to be borne out by data. We emphasize that these alternative models also are not perfect, and further research is needed to identify even better approaches.

Participants in means-tested programs must periodically document eligibility through a recertification process. If all cases that fail recertification are ineligible, the exact timing of this process should be irrelevant. We find that later recertification interview assignments for the Supplemental Nutrition Assistance Program (SNAP), which leave less time to reschedule missed interviews, decrease recertification success by 22 percent. The consequences of not recertifying due to later interviews are highly skewed: most cases quickly reenroll, while one-quarter remain off SNAP for over a year. The marginal disenrolled case is as needy as the average participant, suggesting inefficient screening from late interviews. (JEL H51, H75, I12, I18, I38)

Relief of symptoms and alterations of superficial venous pressures as a result of' wearing elastic stockings were assessed in I 2 patients with varicose veins. The efect of wearing elastic stockings on superficial venous pressures was measured in I0 normal volunteers.In the group of patients continuous elastic stocking compression produced relief of symptoms and a lowering of the venous ambulatory pressure.ELASTIC stockings have been used in the treatment of venous insufficiency since the end of the seventeenth century (Foote, 1960). The object of the present work was t o evaluate and correlate the effect of continuous use of elastic stockings on the patients' symptoms and superficial venous pressures. The pressures exerted by the stockings on different parts of the leg were also measured.

An animal study has been carried out on 3 baboons to assess the feasibility of replacing a damaged segment of ureter with a free, non-pedicled, full thickness graft. A 3 cm segment was excised from the middle third of one ureter from each baboon and the free graft (buccal mucosa) fashioned into a tube and interposed between the cut ends in order to replace the excised segment. The grafts were left in situ for up to 10 weeks and their subsequent fate studied radiologically, histologically and by gross specimen examination. The results showed that in all cases perfect viability of the graft was maintained and there was no evidence of graft shrinkage or of loss of patency. In one instance a stricture developed at the mid point of the graft, but this was entirely explicable on technical grounds. Urine drainage was not impaired on account of the insertion of a muscle-free (and therefore aperistaltic) segment into the ureter.

Recipients of means-tested program benefits must periodically document continued eligibility through a recertification process. We find evidence that the administrative burden associated with SNAP recertification leads to decreases in program participation. Cases assigned to later recertification interview dates, which leave less time to reschedule missed interviews, are over 20 percent less likely to recertify than cases assigned to interviews earlier in the month. Cases that fail recertification due to later assignments lose an average of $600 in benefits in the following year. These losses are highly skewed: many cases quickly re-enroll, while one quarter remain off SNAP for over a year post-recertification.

Twenty-three patients who were given intravesical Mitomycin C for treatment of superficial bladder cancer have been followed up for a further 12 and 24 months after an initial assessment 5 weeks after completing therapy. At 5 weeks 17 (74%) showed complete disappearance of tumour and 4 (17%) showed a partial response. Twelve months later 8 (35%) remained tumour-free and 15 (65%) had recurrences; 5 of these (22% of all patients) had progressed to invasive cancer. The results at 24 months were little different except that one further patient (27% in all) progressed to invasive cancer. Six patients with symptomatic carcinoma in situ became symptom-free after Mitomycin C, but despite remaining free of symptoms three have progressed to invasive cancer. This small series shows that involvement of large areas of bladder urothelium by tumour, carcinoma in situ and previous therapy for tumour are unfavourable prognostic indices.

Perfusion studies of the upper urinary tract have been associated (in our hands) with poor reproducibility during repeated studies carried out at the same sitting. In an attempt to overcome this, a fundamental modification of the Whitaker technique has been devised whereby, instead of measuring renal pelvis pressure during constant flow infusion, the flow rate has been measured during constant pressure infusion. The 2 techniques have been compared in a study carried out in normal ureters in anaesthetised dogs. The modified technique not only dispenses with the sophisticated equipment required for this test, but gives results which are more reproducible. In addition, it was noted that the modified technique allowed greater flow rates for given pressure measurements than was possible with the standard Whitaker test. It is thought that these findings are related to the effects of motor-driven syringe pumps, difficulty in data interpretation in some cases with Whitaker's test, and the stretch response of ureteric smooth muscle which may be excessively stimulated during the Whitaker test.

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