Bye-Bye Bias
Methods of data collection are required in order to conduct many research studies and social experiments. Multiple price lists, for example, are a procedure that helps researchers determine an individual’s desire and willingness to purchase products or services of use. This process asks participants to fill out a table comparing an object to its price, where they then mark “yes” or “no,” indicating whether or not they would buy the product. While this method is a simple procedure, there is evidence of bias and high error rates. Choice patterns including “multiple switching” and “never switching” have the capacity to further skew the results of such experiments. These effects are made apparent by a South African choice experiment that revealed discrepancies in subject preferences as a result of order changes.
In order to combat the often incorrect conclusions, UC Santa Barbara researcher B. Kelsey Jack has worked in conjunction with Kathryn McDermott and Anja Sautmann from Cape Town, South Africa and the Development Economics Research Group of the World Bank in proposing a new method of data collecting. Their model uses a combination of random-effect latent utility and random approach models that would eradicate the error and bias from the data. This two-part approach randomizes the order by which the prices are shown to the participants in order to account for the possibility of choice pattern. The latent utility model is scaled appropriately in accommodation of inconsistencies and dominated choices. This process further eliminates the selection bias that commonly arises in this form of experimentation. Further development of this project paves the way for more accurate research studies and better understanding for relevant economical and scientific analysis, including the explanation of treatment effects and insight about welfare.
Defining Deforestation:
While it is generally understood that agriculture is largely responsible for global deforestation, there are several forms of agricultural development which have varying levels of impact on forest ecosystems. A team of scientists from all over the world, including UCSB environmental studies professor Robert Heilmayr, has striven to shed light on the breakdown of deforestation due to these different phenomena. The foremost way in which we usually perceive agriculture contributing to deforestation is by direct causes such as forest clearing for pastures and plantations of crops such as palm oil, soy and coffee. However, despite causes like these making up the majority (~90-99%) of tropical deforestation, the researchers found that, surprisingly, only about half of that land is actually converted into “productive agricultural land.” In their paper, they include a graphic that expresses that a significant portion of deforestation is due to secondary effects which may ultimately lead to that land being abandoned. Such effects include: crop booms and busts, land speculation, low suitability of land and/or inadequate management, and even fires spreading from other areas of land clearing. Additionally, they found that approximately a third of agriculture encroachment into forests is consumer driven (in producer countries.) Some examples of high-demand exports they list in the paper are beef and cereal products, which they state account for the majority of deforestation across Africa. Of course the full extent of deforestation and its causes are still not fully understood, but this team’s research and analysis of existing data provide valuable insight into the topics of land use and environmental degradation, as well as provide solid groundwork for future studies.
Into the Light
A team of researchers has recently discovered new details in the visual mechanisms of Drosophila. It has been documented that upon exposure to light, photoreceptors in the eye stimulate a cascade of events ultimately leading to the generation of lipids that stimulate an influx of calcium ions through the TRP and TRPL cation channel. However, the exact lipids that were produced in response to the light were unknown. In order to determine which lipids opened the ion channels, they set up an experiment in which groups of flies were placed in the dark and the light, and whose lipids were then analyzed after exposure to light. The team, including UC Santa Barbara MCDB researchers Takaaki Sokabe, Avinash Chandel, and Craig Montell, identified the endocannabinoids – molecules produced by the body (as opposed to those found in cannabis compounds) that play roles in regulating various metabolic processes – that played a role in triggering the cation channels. Additionally, the authors asserted that since Drosophila lacks cannabinoid receptors that are homologous to those in mammals, TRP and TRPL must be the endogenous (produced by the body) receptor equivalents for endocannabinoids in Drosophila. The findings of this research are significant as they shed light on the already well-known and well-studied complex eye structure of Drosophila, while the broader implications are significant due to the importance of organisms being able to use their senses to better understand their environment and make educated choices based on the information they obtain.
