Identification of academic peer effects in college: Does data aggregation matter?

This study exploited random roommate assignments in a small Chinese college to estimate the causal effects of roommates’ scores on the national College Entrance Test (CET) on first-year students’ Grade Point Average (GPA). Analyzing data on an entire cohort of enrolled students, we found that the level of aggregation, for both the peer-ability measure and one’s own academic-outcome measure, matters for the identification of academic peer effects. Specifically, while roommates’ average CET score has a barely significant impact, the highest-scoring roommate’s CET score has a strong positive impact. Peer effects are also larger for one’s GPA for required courses than that of elective courses. Finally, peer effects in both types of courses decline over time while the effects of one’s own CET score increase over time, suggesting that students in this college tend to substitute their own ability for peer ability as they become more academically independent

The Research and Development on CTJ10/96-6, the Strong Exhaust Driven by Air Pressure Sanitary Device of the Mine Rescue System

According to the technical specification requirements of the mine rescue system, CTJ10/96-6, we design a strong exhaust sanitary device driven by air pressure based on pneumatic control, which adopts a key control by mechanical button. It implements many functions, such as flushing and sealing the smell, measuring and strong exhaust by using mechanical and pneumatic transmission. It also meets the demand of design requirements for the safety and explosion-proof of the mine rescue system.

A Method for forcasting Salinity Process in Seawater-Intruded Rivers

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

INTERVENTION EFFECT OF THE INTEGRATION MODEL ON NEGATIVE EMOTIONS OF ADOLESCENTS DURING THE OUTBREAK OF CORONA VIRUS DISEASE 2019

Background: The World Health Organization has declared the Corona Virus Disease 2019 (COVID-19) epidemic as a public health emergency of international concern. Given the sudden infection from and extensive dispersion of COVID-19 and the absence of specific drugs, those infected are in danger if they are not treated in time. Consequently, COVID-19 has become an important factor influencing adolescents’ mental health. The purpose of this study is to explore the intervention effect of the integration model on the negative emotions of adolescents during the COVID-19 epidemic. Subjects and methods: Adolescents were randomly selected from five middle schools in Zhejiang Province of China from May 2020 to July 2020. First, the Self-rating Anxiety Scale, Positive and Negative Affect Scale, and Psychological Well-Being Scale were used for measurement. Then, 72 patients with moderate and severe anxiety symptoms were chosen as the research objects, and the intervention and comparison time was determined to be eight weeks. The subjects were randomly divided into the experiment group (35 members) and the control group (34 members). The integration model was employed on the experiment group. Results: Grade, physical condition, and sleep time are important factors influencing the anxiety level of adolescents during the COVID-19 period, and the anxiety risk of adolescents is higher during their third year of junior high school. After the intervention, the SAS score of the experiment group is lower than that of the control group, and the decrease in the SAS score is higher in the experiment group than in the control group (P<0.01). Moreover, the positive emotion score of the experiment group is higher than that of the control group, and the negative emotion score of the former is lower than that of the latter. The variances in the positive and negative emotion scores are higher in the experiment group than in the control group (P<0.01). The variance in the overall wellbeing index is also greater in the experiment group than in the control group (P<0.01). Conclusion: The intervention using the integrated model can significantly reduce negative emotions such as anxiety, increase positive emotions, and improve the overall well-being of adolescents during the epidemic period

Matching with Couples: Stability and Algorithm

This paper defines a notion of semi-stability for matching problem with couples, which is a natural generalization of, and further identical to, the conventional stability for matching without couples. It is shown that there always exists a semi-stable matching for couples markets with strict preferences, and the set of semi-stable matchings can be partitioned into subsets, each of which forms a distributive lattice. We further prove that a semi-stable matching is stable when couples play reservation strategies. This result perfectly explains the puzzle of NRMP even for finite markets. Moreover, we define a notion of asymptotic stability and present sufficient conditions for a sequential couples market to be asymptotically stable. Another remarkable contribution is that we develop a new algorithm, called Persistent Improvement Algorithm, for finding semi-stable matchings, which is also more efficient than the Gale-Shapley algorithm for finding stable matchings for singles markets. Lastly, this paper investigates the welfare property and incentive issues of semi-stable mechanisms