Barriers to Successful End-User Programming

In my research and my personal life, I have come to know numerous people that our research community might call end-user programmers. Some of them are scientists, some are artists, others are educators and other types of professionals. One thing that all of these people have in common is that their goals are entirely unrelated to producing code. In some cases, programming may be a necessary part of accomplishing their goals, such as a physicist writing a simulation in C or an interaction designer creating an interactive prototype. In other cases, programming may simply be the more efficient alternative to manually solving a problem: one might find duplicate entries in an address book by visual search or by writing a short Perl script

Changing home care aides: Differences between family and non-family care in California Medicaid home and community-based services.

In California Medicaid home-and-community-based services (HCBS), recipients' family members receive payment as home care aides (HCAs). We analyzed data on first-time HCBS recipients to examine factors associated with the likelihood of switching HCAs within the first year of services. Those with family HCAs were less than half as likely to change than those with non-family HCAs and racial/ethnic minorities with non-family HCAs had the highest switching rates. Lower wages and local unemployment were associated with switching of non-family HCAs but not family HCAs. Policymakers can foster continuity of home care by paying family members for home care and raising worker wages

Understanding Expressions of Unwanted Behaviors in Open Bug Reporting

Open bug reporting allows end-users to express a vast array of unwanted software behaviors. However, users ’ expectations often clash with developers’ implementation intents. We created a classification of seven common expectation violations cited by endusers in bug report descriptions and applied it to 1,000 bug reports from the Mozilla project. Our results show that users largely described bugs as violations of their own personal expectations, of specifications, or of the user community’s expectations. We found a correlation between a reporter’s expression of which expectation was being violated and whether or not the bug would eventually be fixed. Specifically, when bugs were expressed as violations of community expectations rather than personal expectations, they had a better chance of being fixed. 1

Computing and Diagnosing Changes in Unit Test Energy Consumption

Many developers have reason to be concerned with with power consumption. For example, mobile app developers want to minimize how much power their applications draw, while still providing useful functionality. However, developers have few tools to get feedback about changes to their application\u27s power consumption behavior as they implement an application and make changes to it over time. We present a tool that, using a team\u27s existing test cases, performs repeated measurements of energy consumption based on instructions executed, objects generated, and blocking latency, generating a distribution of energy use estimates for each test run, recording these distributions in a time series of distributions over time. Then, when these distributions change substantially, we inform the developer of this change, and offer them diagnostic information about the elements of their code potentially responsible for the change and the inputs responsible. Through this information, we believe that developers will be better enabled to relate recent changes in their code to changes in energy consumption, enabling them to better incorporate changes in software energy consumption into their software evolution decisions

Directed flow of neutral strange particles at AGS

Directed flow of neutral strange particles in heavy ion collisions at AGS is studied in the ART transport model. Using a lambda mean-field potential which is 2/3 of that for a nucleon as predicted by the constituent quark model, lambdas are found to flow with protons but with a smaller flow parameter as observed in experiments. For kaons, their repulsive potential, which is calculated from the impulse approximation using the measured kaon-nucleon scattering length, leads to a smaller anti-flow than that shown in the preliminary E895 data. Implications of this discrepancy are discussed.Comment: 6 pages, 2 figure

Constraining properties of neutron stars with heavy-ion reactions in terrestrial laboratories

Heavy-ion reactions provide a unique means to investigate the equation of state (EOS) of neutron-rich nuclear matter, especially the density dependence of the nuclear symmetry energy $E_{sym}(\rho)$. The latter plays an important role in understanding many key issues in both nuclear physics and astrophysics. Recent analyses of heavy-ion reactions have already put a stringent constraint on the $E_{sym}(\rho)$ around the saturation density. This subsequently allowed us to constrain significantly the radii and cooling mechanisms of neutron stars as well as the possible changing rate of the gravitational constant G.Comment: 6 pages. Talk given at the Nuclear Physics in Astrophysics III, Dresden, Germany, March 26-31, 2007. To appear in a special volume of J. of Phys.