Relativistic financial decisions : context effects on retirement saving and investment risk preferences

We report a study of the effects the choice set on financial decision making related to retirement savings and risky investment. The participants were presented with either a full range of choice options or a limited subset of the feasible options. The choices of saving and risk are affected by the position of each option in the range of presented options. This result demonstrated that the range of the options offered as possible saving rates and levels of investment risk influences decisions about saving and risk. The study was conducted on a sample of working people, and we controlled whether the participants can financially afford in their real life the decisions taken in the test. In addition, various measures of risk aversion did not account for the risk taken in each condition. Surprisingly, only the simplest and most direct risk preference measure was a significant predictor of the responses within a particular choice set context, although the actual choices were still very much influenced by the range. Thus, the results reported here suggest that financial judgments and choices are relative, which corroborates, in an important practical domain, previous related work with abstract gambles and hypothetical risky investments

Dimensionality of risk perception : factors affecting consumer understanding and evaluation of financial risk

This article describes two studies of the factors affecting consumer understanding of financial risk. The first study investigated factors affecting people's perception and comprehension of information about the risks related to retirement investments. First, we asked respondents to list possible risk factors related to investment in a pension plan. Then we obtained ratings of different factors (e.g., the perceived level of knowledge about an investment) that could affect perception of the risk of financial products and retirement investment decisions. Finally, we asked the subjects to rate 11 different descriptions presenting risk information about the same financial product. The risk information framing that received highest rating presented risk as variation between minimum and maximum values with an average in between. The second study demonstrated the risk framing that received highest ranking also prompted more stable risk preferences over a 3-month testing period in comparison to standard measures of risk aversion. Thus, the second study corroborated the importance of the findings in the first study and also indicated that, although people can exhibit stable risk preferences if we ask them the right questions, these preferences were very specific to the risk domain

Risk preference discrepancy : a prospect relativity account of the discrepancy between risk preferences in laboratory gambles and real world investments

In this article, we presented evidence that people are more risk averse when investing in financial products in the real world than when they make risky choices between gambles in laboratory experiments. In order to provide an account for this discrepancy, we conducted experiments, which showed that the range of offered investment funds that vary in their riskreward characteristics had a significant effect on the distribution of hypothetical funds to those products. We also showed that people are able to use the context provided by the choice set in order the make relative riskiness judgments for investment products. This context dependent relativistic nature of risk preferences is proposed as a plausible explanation of the risk preference discrepancy between laboratory experiments and real-world investments. We also discuss other possible theoretical interpretations of the discrepancy

CFD modelling of two-phase stirred bioreaction systems by segregated solution of the Euler–Euler model

An advanced study of a bioreactor system involving a Navier–Stokes based model has been accomplished. The model allows a more realistic impeller induced flow image to be combined with the Monod bioreaction kinetics reported previously. The time-course of gluconic acid production by Aspergillus niger strain is simulated at kinetic conditions proposed in the literature. The simulation is based on (1) a stepwise solution strategy resolving first the fluid flow field, further imposing oxygen mass transfer and bioreaction with subsequent analysis of flow interactions, and (2) a segregated solution of the model replacing the multiple iterations per grid cell with single iterations. The numerical results are compared with experimental data for the bioreaction dynamics and show satisfactory agreement. The model is used for assessment of the viscosity effect upon the bioreactor performance. A 10-fold viscosity rise results in 2-fold decrease of KLa and 25% decrease of the specific gluconic acid production rate. The model allows better understanding of the mechanism of the important bioprocess

CFD stimulation of gluconic acid production in a stirred gas-liquid fermenter

Designing large-scale stirred bioreactors with performance closely matching the one achieved in lab-scale fermenters presents continuous challenge. In this contribution, dynamic modelling of the aerobic biocatalytic conversion process in viscous batch stirred tank reactor is developed. Its operation is illustrated by simulation of the interaction of fluid flow, mass transfer and reaction relevant to gluconic acid production by a strictly aerophilic Aspergiluc niger based on a “twofluid” model. As a result of this simulation, the velocity fields, the local substrate, dissolved oxygen, product and biomass concentration profiles were obtained. Constant bubble size and global gas-liquid mass transfer were assumed. The algorithm employed could be used for fast evaluation procedures regarding predictions and feedback control of aerobic bioreactor performance

The purchase of agricultural land a well thought out process in the agribusiness enterprises

The changing economic environment has and will continue to have an impact on the price of agricultural land and lease. It is the possession of this main asset for production (agricultural land) that is becoming increasingly important for the processes in the Agribusiness enterprises. The purpose of the article is to explore and present possible models for assessing the need to own agricultural land and how this asset affects the processes in the Agribusiness enterprises. The results focus on the need to identify and build a proper strategy in the Agribusiness enterprises, trends and processes in the pricing of land properties. The subject of the study is the determinants leading to changes in the prices of the agricultural land and lease, and their impact on the processes in the Agribusiness enterprises. The survey covers processes related to price dynamics, both at national level and external effects, determining trends in the country