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Regression Models for Understanding COVID-19 Epidemic Dynamics With Incomplete Data
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| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Journal of the American Statistical Association |
| Volume / Edisi | : | 116 (No. 536) |
| Halaman | : | 1561-1577 |
| Abstrak | : | Modeling infectious disease dynamics has been critical throughout the COVID-19 pandemic. Of particular interest are the incidence, prevalence, and effective reproductive number (Rt ). Estimating these quantities is challenging due to under-ascertainment, unreliable reporting, and time lags between infection, onset, and testing. We propose a Multilevel Epidemic Regression Model to Account for Incomplete Data (MERMAID) to jointly estimate Rt , ascertainment rates, incidence, and prevalence over time in one or multiple regions. Specifically, MERMAID allows for a flexible regression model of Rt that can incorporate geographic and time-varying covariates. To account for under-ascertainment, we (a) model the ascertainment probability over time as a function of testing metrics and (b) jointly model data on confirmed infections and population-based serological surveys. To account for delays between infection, onset, and reporting, we model stochastic lag times as missing data, and develop an EM algorithm to estimate the model parameters. We evaluate the performance of MERMAID in simulation studies, and assess its robustness by conducting sensitivity analyses in a range of scenarios of model misspecifications. We apply the proposed method to analyze COVID-19 daily confirmed infection counts, PCR testing data, and serological survey data across the United States. Based on our model, we estimate an overall COVID-19 prevalence of 12.5% (ranging from 2.4% in Maine to 20.2% in New York) and an overall ascertainment rate of 45.5% (ranging from 22.5% in New York to 81.3% in Rhode Island) in the United States from March to December 2020. Supplementary materials for this article, including a standardized description of the materials available for reproducing the work, are available as an online supplement. |
MASALAH KRISIS DOLLAR AMERIKA SERIKAT DAN PENGARUHNYA ATAS NILAI RUPIAH
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Analisa |
| Volume / Edisi | : | VII-1, JANUARI (No. 1) |
| Halaman | : | 37-63 |
| Abstrak | : | - |
PERLOMBAAN TIMUR-BARAT DI KAWASAN SAMUDERA HINDIA
| Pengarang | : | Dipoyudo Kirdi |
| Nama Majalah/Jurnal | : | Analisa |
| Volume / Edisi | : | VII-1, JANUARI (No. 1) |
| Halaman | : | 21-36 |
| Abstrak | : | - |
INDONESIA DAN FOKUS BISNIS INTERNASIONAL DALAM TAHUN 1978
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Analisa |
| Volume / Edisi | : | VII-1, JANUARI (No. 1) |
| Halaman | : | 5-20 |
| Abstrak | : | - |
Students’ Perspectives of a Science Enrichment Programme: Out?of?school inquiry as access
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | International Journal of Science Education |
| Volume / Edisi | : | 31 (No. 13) |
| Halaman | : | 1831-1855 |
| Abstrak | : | Science enrichment programmes housed outside traditional school settings can offer students from traditionally under?resourced schools valuable opportunities to access authentic scientific tools and practices. The present study contributes to our understanding of this potential and how it can best be realised through an analysis of the students’ own perspectives on a specific out?of?school programme—a one?year partnership with a university?based science outreach programme, which culminated in a half?day laboratory experience for a total of 292 secondary students (ages 11–18 years). Extensive data were collected on this experience, including detailed field notes and video recordings of the classes’ visits to the university as well as the planning meetings with teachers at the beginning and end of the school year, surveys of the participating students, and surveys and interviews of the teachers, and were analysed both qualitatively and quantitatively using a grounded theory approach. Building on the valuable perspectives of the participating students, and comparing them with those of their eight teachers, this study confirms that carefully designed collaborative out?of?school inquiry programmes have the potential to broaden students’ (especially those from under?resourced schools) experiences of science as well as bridge them to school science. |
Exploring Taiwanese High School Students’ Perceptions of and Preferences for Teacher Authority in the Earth Science Classroom with Relation to their Attitudes and Achievement
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | International Journal of Science Education |
| Volume / Edisi | : | 31 (No. 13) |
| Halaman | : | 1811-1830 |
| Abstrak | : | Educational researchers have suggested that the tension between the learner?centred and teacher?centred pedagogies represents a real classroom issue that influences teaching and learning. This issue may be particularly significant in East?Asian countries such as Taiwan due to some cultural influences. For example, teacher authority is highly valued in the culture. Accordingly, the present study aims to develop a questionnaire—the Teacher Authority Survey (TAS), with actual and preferred versions—to explore students’ perceptions/preferences regarding teacher authority in the earth science course. The relationships among students’ perceptions/preferences for teacher authority, learning attitudes, and learning achievements were investigated. Six hundred and seventeen Taiwanese high school students were administered the TAS, the earth science attitudinal questionnaire, and achievement assessment. Both exploratory and confirmatory factor analyses indicated that the TAS developed in this study has satisfactory validity and reliability measures. Correlation analysis indicated that the classrooms more oriented to learner?centredness were correlated with more favourable attitudes toward learning. Moreover, three clusters of preferred teacher authority—namely, teacher?centred authority, uncertain authority, and sharing authority—were identified. Students who preferred sharing authority tended to have more favourable learning attitudes, whereas students in the uncertain authority group seemed to have lower earth science attitudes and achievements. |
School Innovation in Science: Improving science teaching and learning in Australian schools
| Pengarang | : | Russell Tytler |
| Nama Majalah/Jurnal | : | International Journal of Science Education |
| Volume / Edisi | : | 31 (No. 13) |
| Halaman | : | 1777-1809 |
| Abstrak | : | School Innovation in Science is a major Victorian Government initiative that developed and validated a model whereby schools can improve their science teaching and learning. The initiative was developed and rolled out to more than 400 schools over the period 2000–2004. A research team worked with 200+ primary and secondary schools over three years, supporting them in developing new initiatives in science, and monitoring the impact on school and classroom practice, and student outcomes. The research effort underpinning the development phase included the development and validation of a set of components describing effective teaching, the refinement of a school and teacher change strategy, the development of instruments to monitor teacher classroom practice and a variety of student outcomes, and the development of insights into the change process using questionnaires, observations, and interviews across four years. This paper describes the project and its major outcomes, and raises a number of issues concerning the nature of school and teacher change, pedagogy, school and community, and student learning, and the way these interact. A number of research issues are raised by the size and developmental nature of the project, the range of research methods, and the different audiences served by the research. The issue of sustainability of such system?wide change initiatives is discussed. |
Impacts of Multi?representational Instruction on High School Students’ Conceptual Understandings of the Particulate Nature of Matter
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | International Journal of Science Education |
| Volume / Edisi | : | 31 (No. 13) |
| Halaman | : | 1743-1775 |
| Abstrak | : | This quasi?experimental study examined 42 high school introductory chemistry students’ conceptual understandings of the particulate nature of matter (PNM) before and immediately after instruction. Two groups of students, who were taught by the same teacher, received one of two possible instructional interventions: Reform?Based Teaching (RBT) or Reform?Based Teaching with Multiple Representations (RBTw/MR). The RBTw/MR instruction differed from the RBT instruction in terms of the frequency of using multiple representations (visual, textual, oral) in relationship to the macroscopic phenomenon and the likely actions occurring at the submicroscopic level. Qualitative research methods, including open?ended questionnaires and interviews, were used to investigate and describe participants’ conceptual understandings of the PNM over time. The findings indicated that before instruction all participants held a range of alternative conceptions about the aspects of the PNM. Post?instruction findings indicate that the RBTw/MR instruction was more efficacious in promoting a scientific understanding of the PNM than was the instruction without multiple representations. |
Reliance to Independence: Approaches to learning in peer?led undergraduate science, technology, engineering, and mathematics workshops
| Pengarang | : | Marina Micari |
| Nama Majalah/Jurnal | : | International Journal of Science Education |
| Volume / Edisi | : | 31 (No. 13) |
| Halaman | : | 1713-1741 |
| Abstrak | : | The phenomenographic ‘approach to learning’ literature holds that students’ approaches to learning can change depending on the learning context. This implies that, by modifying the learning context, teachers can change the way students approach learning, and this can ultimately lead to a change in learning outcomes. The study presented here examines one effort to modify a science, technology, engineering, and mathematics (STEM) learning context and the approaches to learning taken by students experiencing this environment. Using a qualitative, phenomenographic approach, we interviewed 45 students in a STEM peer?led workshop programme at a large US research university. Similar to previous approach?to?learning research, the study identified three approaches students took to learning in the peer?led programme, in which they focused on simply making it through the course, engaging more meaningfully with the material, and gaining better control over their own learning. |
Would You Want to Talk to a Scientist at a Party? High school students’ attitudes to school science and to science
| Pengarang | : | Judith Bennett |
| Nama Majalah/Jurnal | : | International Journal of Science Education |
| Volume / Edisi | : | 31 (No. 14) |
| Halaman | : | 1975-1998 |
| Abstrak | : | The present paper describes a four?year project involving the development of a new instrument, the Attitudes to School Science and Science instrument, and its use to collect baseline attitudinal data from 280 students aged 11, 14, and 16 years. A key feature of the instrument is that it collects both descriptive and explanatory data in a pencil?and?paper format. The data gathered are probed in detail for explanatory insights into features that have emerged from more recent research on attitudes to science, in particular the suggestions that students view science outside school more positively than their experiences in science lessons, and that the early years of secondary education (ages approximately 11–14 years) are the most crucial in shaping attitudes. The study shows that positive attitudes to school science decline significantly between the ages of 11 and 14 years, with little appreciable downward change beyond this and, in some cases, a slight upturn. Female students display less positive attitudes and less clear?cut views on a variety of aspects of science. A sense of science being important in general terms, although not having much appeal for individual students, also emerged clearly from the data. The paper suggests that attitudinal instruments have a role to play in research, but that these need to be complemented by studies of detailed features of schools that may influence attitudes, some of which may not be apparent from data collected from students. |