Design principles from the field of design engineering require that a product be designed as unambiguous, safe and simple as possible. Simplicity results on the one hand from an objective product-relevant side, on the other hand from the experience and knowledge of the user. A product that is perceived as simple by one person may seem complicated to another. From this, the questions arise, with which attributes simplicity can be described and how these are to be captured. In this paper, an evaluation system for the subjective attributes of simplicity is created using the fuzzy sets approach.

Weed management decision aids have proliferated in recent years, but none of them have been rigorously compared with actual farmer weed management on farm fields. This research compares the Michigan WEEDSIM/GWM bioeconomic model and the CORNHERB and SOYHERB herbicide selection models with farmer weed management in Michigan. In 19 site-years of research in corn and soybean during 1996 to 1997, we found that crop yield, weed control costs, and gross margin over weed control costs (profitability) with the computerized decision aids were not statistically superior to the farmer treatments, even at a one-sided threshold of P = 0.10. In corn the gross margin of the farmer treatment ranked highest in both years. In soybean the gross margin of the SOYHERB treatment ranked highest in 1996 and that of the WEEDSIM/GWM treatment was highest in 1997. Overall, the farmer treatment had the highest gross margin 5½ times, the CORNHERB–SOYHERB treatment 6 times, and the WEEDSIM/GWM treatment 7½ times (where ties were divided equally to give 1/2 to each). However, none of these rank differences corresponded to a statistically significant gross margin gain over the farmer treatment.

Objectives: Herpes zoster (HZ) is characterized by a painful skin rash. Its main complication is postherpetic neuralgia (PHN), pain persisting or occurring after the rash onset. HZ treatment aims to reduce acute pain, impede the onset complications, and disease progression. The aim of this study was to assess the cost-effectiveness of HZ vaccination compared with no vaccination strategy, within the Italian context.

Methods: The natural history of HZ and PHN was mapped through a Markov model with lifetime horizon. A population of patients aged between 60 and 79 years was hypothesized. Third party payer (Italian National Health Service, I-NHS) and societal perspectives were adopted. Data were derived from literature.

Results and Conclusions: The incremental cost-effectiveness ratio of the vaccination equaled EUR 11,943 per quality-adjusted life-year (QALY) under the I-NHS perspective and EUR 11,248 per QALY under the societal perspective. Considering a cost-effectiveness threshold of EUR 30,000/QALY, the multi-way sensitivity analysis showed that vaccination is cost-effective regardless of the perspective adopted, in 99 percent of simulations.

A linear programming algorithm is used to estimate the parameters of a wheat storage decision model. This approach allows objective functions other than minimization of error squared to be used. It is demonstrated that by using a profit maximization objective function, an improved wheat storage decision model can be developed.