Heterogeneous interpretation of “household expenditure” in survey reports: Evidence and implications of bias

This paper addresses respondents’ interpretation of the term “household expenditure” when answering survey questions. A sizeable minority of respondents do not attempt to include all transactions made by every household member, interpreting the question as eliciting individual consumption. This biases estimates of expenditure downward. Furthermore, this bias is predicted by respondent characteristics.Household Expenditure, Survey Methods, Measurement Error

Causes and consequences of variation in maternal investment strategies

Females across taxa increase fitness by investing resources and care to offspring. However, numerous intrinsic and extrinsic factors influence both female and offspring performance and survival. Such complexity leads to tradeoffs in investment and variety in investment strategies. For iteroparous species, females must balance investment into reproduction with their own survival and future reproduction. In this dissertation, I examine how females balance numerous pressures on investment with an emphasis on how investment strategies vary across life. In chapter two, I tested how maternal predation risk influences nest-site choice, and how maternal responses to risk affect offspring survival in painted turtles (Chrysemys picta). I compared young and old mothers to assess if response to risk varies depending upon maternal age. I predicted that young mothers would invest heavily in themselves (i.e., nest closer to the safety of water) whereas older mothers would invest more into current reproduction (i.e., nest farther from the shore because of lower nest predation risk). Contrary to predictions, neither young nor old females altered how far they nested from water after perceiving elevated risk. Nevertheless, older females nested farther from water than younger females, which is likely driven by lower future reproductive potential (i.e., residual reproductive value, RRV) in older females. In chapter three, I assessed how offspring phenotype influences investment strategy in common snapping turtles (Chelydra serpentina). I released hatchling turtles at varying distances from water and monitored survival during overland dispersal. Survival decreased with dispersal distance. However, bigger hatchlings were less affected by increasing dispersal distance. Moreover, females producing larger and better dispersing offspring oviposited farther from water than females that produced smaller and poorer dispersing offspring. These findings suggest female investment can be sensitive to offspring phenotype and that such covariation between nest-site choice and offspring dispersal ability can maximize offspring survival and, thus, maternal fitness. In chapter four, I examined how age and RRV compare in explaining variation in a risky investment behavior (i.e., distance females construct nests from water) in painted turtles. Previous work (in addition to chapter 2) has shown that older females nest farther from water than younger mothers and suggested this effect is driven by RRV. I predicted that RRV would explain more variation in distance to water than age because RRV accounts for any nonlinearity in future reproductive potential across age. Contrary to my prediction, age was a better predictor of nest distance to water than RRV. This finding suggests a stronger correlate of age (e.g., body size) may be more responsible for shaping the distance females nest from water than previously appreciated. Collectively, this work suggests nest-site choice is a complex behavior that is shaped by numerous factors, many of which interact. Moreover, investment strategies shift across age to maximize lifetime fitness in freshwater turtles

Experimental Tests of Survey Responses to Expenditure Questions

This paper tests for a number of survey effects in the elicitation of expenditure items. In particular we examine the extent to which individuals use features of the expenditure question to construct their answers. We test whether respondents interpret question wording as researchers intend and examine the extent to which prompts, clarifications and seemingly arbitrary features of survey design influence expenditure reports. We find that over one quarter of respondents have difficulty distinguishing between "you" and “your household” when making expenditure reports; that respondents report higher pro-rata expenditure when asked to give responses on a weekly as opposed to monthly or annual time scale; that respondents give higher estimates when using a scale with a higher mid-point; and that respondents report higher aggregated expenditure when categories are presented in a disaggregated form. In summary, expenditure reports are constructed using convenient rules of thumb and available information, which will depend on the characteristics of the respondent, the expenditure domain and features of the survey question. It is crucial to further account for these features in ongoing surveys.expenditure surveys, survey design, data experiments

Widening the Aperture on Fourth Amendment Interests: A Comment on Orin Kerr\u27s The Fourth Amendment and the Global Internet

Physical-world law may not be suitable for cyberspace. For example, the Supreme Court\u27s sufficient connection test in U.S. v. Verdugo-Urquidez (1990) is inconsistent with the century-long trend for courts to find greater constitutional protections for those subject to U.S. jurisdiction outside the United States. Courts must maintain flexibility to conceive of a Fourth Amendment that does not depend exclusively on territory to fulfill its twin aims of ordering government and enabling redress of liberty infringements. Federal and state courts and legislatures addressing searches, seizures, and surveillance in cyberspace should seek simple rules that can easily adapt as cyberspace and government uses of cyberspace evolve

Widening the Aperture on Fourth Amendment Interests: A Comment on Orin Kerr\u27s The Fourth Amendment and the Global Internet

Physical-world law may not be suitable for cyberspace. For example, the Supreme Court\u27s sufficient connection test in U.S. v. Verdugo-Urquidez (1990) is inconsistent with the century-long trend for courts to find greater constitutional protections for those subject to U.S. jurisdiction outside the United States. Courts must maintain flexibility to conceive of a Fourth Amendment that does not depend exclusively on territory to fulfill its twin aims of ordering government and enabling redress of liberty infringements. Federal and state courts and legislatures addressing searches, seizures, and surveillance in cyberspace should seek simple rules that can easily adapt as cyberspace and government uses of cyberspace evolve

A finite element approach to self-consistent field theory calculations of multiblock polymers

Self-consistent field theory (SCFT) has proven to be a powerful tool for modeling equilibrium microstructures of soft materials, particularly for multiblock polymers. A very successful approach to numerically solving the SCFT set of equations is based on using a spectral approach. While widely successful, this approach has limitations especially in the context of current technologically relevant applications. These limitations include non-trivial approaches for modeling complex geometries, difficulties in extending to non-periodic domains, as well as non-trivial extensions for spatial adaptivity. As a viable alternative to spectral schemes, we develop a finite element formulation of the SCFT paradigm for calculating equilibrium polymer morphologies. We discuss the formulation and address implementation challenges that ensure accuracy and efficiency. We explore higher order chain contour steppers that are efficiently implemented with Richardson Extrapolation. This approach is highly scalable and suitable for systems with arbitrary shapes. We show spatial and temporal convergence and illustrate scaling on up to 2048 cores. Finally, we illustrate confinement effects for selected complex geometries. This has implications for materials design for nanoscale applications where dimensions are such that equilibrium morphologies dramatically differ from the bulk phases

Cybersecurity and the Administrative National Security State: Framing the Issues for Federal Legislation

In the digital age, every part of federal government has critical cybersecurity interests. Many of those issues are brought into sharp focus by Edward Snowden\u27s disclosure of sensitive government cyber intelligence programs conducted by the National Security Agency, the Federal Bureau of Investigation, and the Central Intelligence Agency. Courts are reviewing various constitutional and statutory challenges to those programs, two government review groups have reported on related legal and policy issues, and Congress is considering cyber intelligence reform proposals. All of this action comes on the heels of significant efforts by successive administrations to restructure government and pass comprehensive cybersecurity legislation to improve the nation\u27s posture to strategically address cyber issues. This Article proposes that new framework legislation is needed to comprehensively address issues relating to Snowden\u27s disclosures and broader cybersecurity interests