Where Do New US-Trained Science-Engineering PhDs come from?

This study shows that the demographic and institutional origins of new US trained science and engineering PhDs changed markedly between the late 1960s-1970s to the 1990s-early 2000s. In 1966, 71% of science and engineering PhD graduates were US-born males, 6% were US-born females, and 23% were foreign born. In 2000, 36% of the graduates were US-born males, 25% were US-born females, and 39% were foreign born. Between 1970 and 2000 most of the growth in PhDs was in less prestigious smaller doctorate programs. The undergraduate origins of bachelor's obtaining science and engineering PhDs changed only modestly among US colleges and universities while there was a huge growth in the number of foreign bachelor's graduates obtaining US PhDs.

Short- and Long-Term Outcomes of the Left Behind in China: Education, Well-Being and Life Opportunities

This report addresses the scope of China’s left-behind phenomenon and its roots in migration and education policies. It reviews evidence about disadvantages associated with left-behind status and discusses recent policy responses to the left-behind phenomenon. Empirical evidence is drawn from a national study of middle school students and a 15-year longitudinal case-study of children from rural Gansu, China. While a number of prior studies have shown mixed findings about the scale of educational disadvantage of left-behind children, compared to other groups, evidence presented here indicates that even after adjusting for school or community and household socioeconomic status, there are multiple domains in which homes of left-behind children are disadvantaged. They tend to live in households characterized by poorer health resources, cultural resources and social resources. By definition, they lose access, at least temporarily, to the “human capital” of their absent parents. Children in the short term thus experience more physiological, psychological, and (in the national comparison) educational disadvantages than their non-left-behind counterparts. In the long-term, our case study from Gansu Province suggests that father absence is associated with reduced educational attainment and possibly greater propensity to migrate, but not employment or long-term family relations. Overall, disadvantages appear to be more consistent and more generalized for mother-absent and dual-parent-absent families than for father-absent families. We discuss policy responses, and possible policy strategies, in the closing segment of the report. Policy reforms that obviate the need for children to be left behind are one evident solution to the problem, and some steps appear to be happening in this direction, but local resistance may be substantial. More immediately, boarding schools and community centers are commonly-proposed policy solutions to address the immediate needs of left-behind children, with promise but some clear pitfalls. Other possible supports are discussed

Effect Pathways of Informal Family Separation on Children’s Outcomes: Paternal Labor Migration and Long-term Educational Attainment of Left-Behind Children in Rural China

Informal family separation due to parental labor migration is an increasingly common experience in the lives of children in many countries. This paper proposes a framework and method for analyzing “effect pathways” by which parental labor migration might affect children’s outcomes. The framework incorporates home-environment and child-development mechanisms and is adapted from migration, sociology of education and child development literatures. We test these pathways using data on father absence and long-term educational outcomes for girls and boys in China. We apply structural equation models with inverse probability of treatment weighting to data from a 15-year longitudinal survey of 2,000 children. Significantly, fathers’ migration has distinct implications for different effect pathways. It is associated most significantly with reduced human capital at home, which has the largest detrimental effect on children’s educational attainment, among those studied. At the same time, father absence is associated with better family economic capital and mothers showing more parental warmth, which partially buffer the negative implications of father absence. Overall, father absence corresponds to a reduction of 0.364 years on average in children’s educational attainment, but the reduction is larger for boys than for girls. For boys and girls, the reduced availability of literate adults in the household linked to father absence is an important effect pathway. For girls, this detrimental effect is partially offset by a positive income effect, but for boys, no such positive effect is observed

Pattern Matching Encryption, Strategic Equivalence of Range Voting and Approval Voting, and Statistical Robustness of Voting Rules

We present new results in the areas of cryptography and voting systems. 1. Pattern matching encryption: We present new, general definitions for queryable encryption schemes – encryption schemes that allow evaluation of private queries on encrypted data without performing full decryption. We construct an efficient queryable encryption scheme supporting pattern matching queries, based on suffix trees. Storage and communication complexity are comparable to those for (unencrypted) suffix trees. The construction is based only on symmetric-key primitives, so it is practical. 2. Strategic equivalence of range voting and approval voting: We study strategic voting in the context of range voting in a formal model. We show that under general conditions, as the number of voters becomes large, strategic range voting becomes equivalent to approval voting. We propose beta distributions as a new and interesting way to model voter’s subjective information about other votes. 3. Statistical robustness of voting rules: We introduce a new notion called “sta- tistical robustness” for voting rules: a voting rule is statistically robust if, for any profile of votes, the most likely winner of a sample of the profile is the winner of the complete profile. We show that plurality is the only interesting voting rule that is statistically robust; approval voting (perhaps surprisingly) and other common voting rules are not statistically robust

End-to-end verifiability for optical scan voting systems

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (p. 57-59).End-to-end verifiable voting systems allow voters to verify that their votes are cast as intended, collected as cast, and counted as collected. Essentially, end-to-end voting systems provide voters assurance that each step of the election worked correctly. At the same time, voting systems must protect voter privacy and prevent the possibility of improper voter influence and voter coercion. Several end-to-end voting systems have been proposed, varying in usability and practicality. In this thesis we describe and analyze Scantegrity II, a novel end-to-end verification mechanism for optical scan voting which uses confirmation codes printed on the ballot in invisible ink. The confirmation codes allow voters to create privacy-preserving receipts which voters can check against the bulletin board after the close of the election to ensure that their votes have been collected as cast. Anyone can check that votes have been counted as collected and that the tally is correct. We describe the Scantegrity II system and analyze the integrity and privacy properties it provides.by Emily Shen.S.M

Pattern matching encryption, strategic equivalence of range voting and approval voting, and statistical robustness of voting rules

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 119-123).We present new results in the areas of cryptography and voting systems. 1. Pattern matching encryption: We present new, general definitions for queryable encryption schemes - encryption schemes that allow evaluation of private queries on encrypted data without performing full decryption. We construct an efficient queryable encryption scheme supporting pattern matching queries, based on suffix trees. Storage and communication complexity are comparable to those for (unencrypted) suffix trees. The construction is based only on symmetric-key primitives, so it is practical. 2. Strategic equivalence of range voting and approval voting: We study strategic voting in the context of range voting in a formal model. We show that under general conditions, as the number of voters becomes large, strategic range-voting becomes equivalent to approval voting. We propose beta distributions as a new and interesting way to model voter's subjective information about other votes. 3. Statistical robustness of voting rules: We introduce a new notion called "statistical robustness" for voting rules: a voting rule is statistically robust if, for any profile of votes, the most likely winner of a sample of the profile is the winner of the complete profile. We show that plurality is the only interesting voting rule that is statistically robust; approval voting (perhaps surprisingly) and other common voting rules are not statistically robust.by Emily Shen.Ph.D

SoK: Cryptographically Protected Database Search

Protected database search systems cryptographically isolate the roles of reading from, writing to, and administering the database. This separation limits unnecessary administrator access and protects data in the case of system breaches. Since protected search was introduced in 2000, the area has grown rapidly; systems are offered by academia, start-ups, and established companies. However, there is no best protected search system or set of techniques. Design of such systems is a balancing act between security, functionality, performance, and usability. This challenge is made more difficult by ongoing database specialization, as some users will want the functionality of SQL, NoSQL, or NewSQL databases. This database evolution will continue, and the protected search community should be able to quickly provide functionality consistent with newly invented databases. At the same time, the community must accurately and clearly characterize the tradeoffs between different approaches. To address these challenges, we provide the following contributions: 1) An identification of the important primitive operations across database paradigms. We find there are a small number of base operations that can be used and combined to support a large number of database paradigms. 2) An evaluation of the current state of protected search systems in implementing these base operations. This evaluation describes the main approaches and tradeoffs for each base operation. Furthermore, it puts protected search in the context of unprotected search, identifying key gaps in functionality. 3) An analysis of attacks against protected search for different base queries. 4) A roadmap and tools for transforming a protected search system into a protected database, including an open-source performance evaluation platform and initial user opinions of protected search.Comment: 20 pages, to appear to IEEE Security and Privac

Building Relationships at The U School: Refining and Enhancing Possi Circles

The U School is a district high school in the Innovation Network of Philadelphia Schools dedicated to preparing students from low-income and underserved communities for college and career. One of the primary structures that has been developed to provide personalized support for students is its advisory system, Possi Circles, representing the Possibilities for students at the U School. These non-academic advisory/support groups of 10-15 students and one faculty leader form during freshman year and remain together for the duration of high school. Research supports the central importance of relationships in helping students, particularly at-risk youth like those at the U School, find success in school and develop lifelong capacities for well-being and achievement. This paper presents a set of recommendations, rooted in the science of positive psychology, for optimizing the form, content, and implementation of Possi Circles, including: a defined pathway to successful Possi Circles with a progression of measurable milestones, additional curriculum for year one Circles, and suggestions for successful implementation