Default Tips

We examine the role of defaults in high-frequency, small-scale choices using unique data on over 13 million NYC taxi rides. We exploit a shift in the set of default tip suggestions presented to customers prior to payment, as the base fare changes from below $15 to above$15. Using a regression discontinuity design, we show that default suggestions have a large impact on tip amounts. These results are supported by a secondary analysis that uses the quasi-random assignment of customers to different cars to examine default effects on all fares above $15. Finally, we highlight a potential cost of setting defaults too high, as a higher proportion of customers opt to leave no credit card tip when presented with the higher suggested amounts

Using Google Classroom in Enhancing Communicative Grammar Use and Attitudes of Non-English Specialized Post Graduates

This research integrates virtual language learning and the Communicative Language Teaching CLT approach for developing grammatical performance and attitudes towards English grammar use. It follows the one-group quasi-experimental design. Participants were randomly selected from the postgraduates General Diploma (41) at Hurghada Faculty of Education, Egypt. Instruments of the research included communicative grammar module through Google classroom application, communicative grammar test and a scale about the attitude towards English grammar use. It discussed how to design, instruct and assess a communicative grammar module by using Google Classroom virtual class. Results of the study showed a development in both the performance of participants’ use of English grammar as well as their positive attitudes towards grammar use. Following a one-group quasi-experimental design, the obtained results showed a development in participants’ grammar use (0.001) and also their positive attitudes (0.001) towards using grammar. Results also showed a strong correlation between the two variable; the coefficient scores were (0.779, 0.928 and 0.892) on Pearson, Kendall and Spearman coefficients respectively

Assessing Core Didactic Competencies of Pre-service English Language Teachers During Practicum: A European Perspective

This research discusses implementing a European document (European Portfolio of Student Teachers of Language EPOSTL) as a selfassessment tool. The research design experiments the European portfolio for pre-service language teachers (EPOSTL), which has been translated by the researcher and published by the Council of Europe. The portfolio is used with the aim of assessing the key teaching competencies of pre-service English language teachers during the teaching practice or the practicum. The paper examines key 5 descriptors of didactic competencies in the EPOSTL which are (Lesson planning- Conducting a lesson- classroom management- Independent learning- Assessment of learning). It highlights implementing the portfolios as means of assessing the competencies of language teachers in pre-service context. Instruments of the research include EPOSTL, teaching competence scale and portfolio assessment rubric. Results of implementing the portfolio on a sample of (N. 30) students at Hurghada Faculty of Education during their practicum (3 groups in 3 official language schools) are reported. The results indicate that using EPOSTL as a self-assessment tool has positive impacts on developing the five areas of the portfolio as measured by the Teaching Competencies Scale (TCS) designed by the researcher. The scale includes the main areas of the EPOSTL to be examined by the students while the fifth area "classroom management" was included as in the EPOSTL with "conducting a lesson" area. The recommendations include: implementing the electronic portfolios as self-assessment tools, the need for assessing didactic competencies using authentic assessment tools and designing valid and reliable tools of assessing the whole teaching practice or “practicum” of pre-service English language teachers

Teaching Phonetics Using A Mobile-Based Application in an EFL Context

Mobile based learning has been an effective mean for learning languages. The aim of this study is three-fold: first, to investigate the process of designing mobile-based application for teaching phonetics in EFL context. The second is to verify the effect of this mobile application on pre-service EFL teachers' achievement of English phonetics at a university level. Finally, it aims to investigate participants' satisfaction towards Mobile Assisted Language Learning. The research implements a mobile based program for developing preservice teachers' segmental elements in a phonetics courses. It deals with how to design the program, implement it and test its results. Participants of the study were (23) pre-service English language teachers at Hurghada Faculty of Education, South Valley University, Egypt. Instruments of the study included a mobile based phonetics module, English phonetics achievement Test and an English Satisfaction scale. Results showed a development in participants' achievement at the level (0.01) in mastering the segmental elements (Phonemes identifications- consonants classificationvowels classification). Participants showed their satisfaction of the application through their positive feedback and responses to the items of the questionnair

Stationary Cylindrical Anisotropic Fluid

We present the whole set of equations with regularity and matching conditions required for the description of physically meaningful stationary cylindrically symmmetric distributions of matter, smoothly matched to Lewis vacuum spacetime. A specific example is given. The electric and magnetic parts of the Weyl tensor are calculated, and it is shown that purely electric solutions are necessarily static. Then, it is shown that no conformally flat stationary cylindrical fluid exits, satisfying regularity and matching conditions.Comment: 17 pages Latex. To appear in Gen.Rel.Gra

Integrating English for Academic Writing Virtual Lab Setting in Pre-Service Math and Science Teacher Education Programs

This research focuses on identifying the effect of integrating English for academic writing virtual lab setting in pre-service math and science teacher education programs. Four instruments were utilized in the different process of the research and the test was reported in the results. It utilized English for academic writing questionnaire to identify the academic writing skills needed for the participants, while a virtual academic writing module was used in the instruction of the target skills. English was utilized for the academic writing test and its rubric was used in the pre-post testing of the participants and their assessment. The participants were pre-service students (N=58) from math and science departments at Hurghada Faculty of Education, South Valley University, Egypt. Using a one-group quasi-experimental design, the research followed a pre and post testing procedure before and after applying the virtual academic writing lab. Results of the study were obtained quantitatively and qualitatively through the test of academic writing and the reflection sheet, respectively. Quantitative results showed that there were significant mean differences between participants' scores at level 0.05≥ in the pre and post testing procedure. These differences were in favor of the post testing of both basic academic writing concepts’ variable and academic writing skills variable (000), as well as the total score of participants’ academic writing (sig .002). Qualitative results also showed the positive attitudes of the participants and their satisfaction with the online module based on the feedback provided during the writing process. Recommendations of the research included integrating online virtual writing labs in pre-service math and science teachers’ education programs as well as integrating academic writing in their academic English courses

Relativistic Compact Objects in Isotropic Coordinates

We present a matrix method for obtaining new classes of exact solutions for Einstein's equations representing static perfect fluid spheres. By means of a matrix transformation, we reduce Einstein's equations to two independent Riccati type differential equations for which three classes of solutions are obtained. One class of the solutions corresponding to the linear barotropic type fluid with an equation of state $p=\gamma \rho$ is discussed in detail.Comment: 9 pages, no figures, accepted for publication in Pramana-Journal of Physic