In this paper, we develop the theory of functional generation of portfolios in an equity market with changing dimension. By introducing dimensional jumps in the market, as well as jumps in stock capitalization between the dimensional jumps, we construct different types of self‐financing stock portfolios (additive, multiplicative, and rank‐based) in a very general setting. Our study explains how a dimensional change caused by a listing or delisting event of a stock, and unexpected shocks in the market, affect portfolio return. We also provide empirical analyses of some classical portfolios, quantifying the impact of dimensional change in portfolio performance relative to the market.
more »
« less
Change theory and theory of change: what’s the difference anyway?
- Award ID(s):
- 1830860
- PAR ID:
- 10192791
- Date Published:
- Journal Name:
- International Journal of STEM Education
- Volume:
- 7
- Issue:
- 1
- ISSN:
- 2196-7822
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
null (Ed.)Abstract This article systematically reviews how change theory has been used in STEM higher educational change between 1995 and 2019. Researchers are increasingly turning to theory to inform the design, implementation, and investigation of educational improvement efforts. Yet, efforts are often siloed by discipline and relevant change theory comes from diverse fields outside of STEM. Thus, there is a need to bring together work across disciplines to investigate which change theories are used and how they inform change efforts. This review is based on 97 peer-reviewed articles. We provide an overview of change theories used in the sample and describe how theory informed the rationale and assumptions of projects, conceptualizations of context, indicators used to determine if goals were met, and intervention design. This review points toward three main findings. Change research in STEM higher education almost always draws on theory about individual change, rather than theory that also attends to the system in which change takes place. Additionally, research in this domain often draws on theory in a superficial fashion, instead of using theory as a lens or guide to directly inform interventions, research questions, measurement and evaluation, data analysis, and data interpretation. Lastly, change researchers are not often drawing on, nor building upon, theories used in other studies. This review identified 40 distinct change theories in 97 papers. This lack of theoretical coherence in a relatively limited domain substantially limits our ability to build collective knowledge about how to achieve change. These findings call for more synthetic theoretical work; greater focus on diversity, equity, and inclusion; and more formal opportunities for scholars to learn about change and change theory.more » « less
-
more » « less
Demands for research to generate impact, along with proliferating institutional regimes for evaluating impact, are a ubiquitous aspect of contemporary scientific practice. Based on participant observation at an agro-environmental research institute in southwest China, this article explores three iterations of a tool for planning and evaluating impactful science called ‘theory of change’ (TOC). Despite their ostensible common grounding in TOC, I show how an impact scientist’s framework, a donor’s monitoring and evaluation regime, and a communication consultant’s branding strategy each suggest very different normative structures for scientific practice. These structures entail: particular horizons towards which scientific research is to be practiced, precise points in time at which the future effects of research are to be anticipated, and specific assumptions about how scientists’ agency should play out across time. Taking the peculiar sensibilities of TOC as a comparative framework, I illuminate IFF scientists’ implicit imaginations of how contemporary science does and should generate effects in the world.
-
Cumulative cultural evolution (CCE) occurs among humans who may be presented with many similar options from which to choose, as well as many social influences and diverse environments. It is unknown what general principles underlie the wide range of CCE dynamics and whether they can all be explained by the same unified paradigm. Here, we present a scalable evolutionary model of discrete choice with social learning, based on a few behavioural science assumptions. This paradigm connects the degree of transparency in social learning to the human tendency to imitate others. Computer simulations and quantitative analysis show the interaction of three primary factors—information transparency, popularity bias and population size—drives the pace of CCE. The model predicts a stable rate of evolutionary change for modest degrees of popularity bias. As popularity bias grows, the transition from gradual to punctuated change occurs, with maladaptive subpopulations arising on their own. When the popularity bias gets too severe, CCE stops. This provides a consistent framework for explaining the rich and complex adaptive dynamics taking place in the real world, such as modern digital media.more » « less
-
A national faculty Community of Practice (CoP) has created a model course for undergraduate infrastructure education as a part of its shared agenda. This CoP has collectively defined the domain of knowledge for undergraduate introductory infrastructure education; co-created and peer-reviewed more than 40 complete lessons for an introductory infrastructure course; shared best practices and resources among members; and provided mentorship to newer members adopting or adapting the materials. The Center for Infrastructure Transformation and Education (CIT-E) considers infrastructure as a system rather than a collection of unrelated structural/environmental/transportation components; even more importantly, this system is conceived of as a social-technical system that must be designed with equity and justice factors prioritized to include the diversity of users’ lived experiences. To that end, CoP members have recently produced learning materials on Equity, Inclusion, and Justice (DEIJ) in infrastructure provision. The operationalizing of CoP as a theory of change by CIT-E has emerged beyond the initial National Science Foundation (NSF) funding a decade ago, employing various change strategies. Example strategies include expanding membership and creating alternative educational practices to support change and transformation. Recent NSF funding and new membership have created opportunities for the CoP to lead change at a much broader level across civil and environmental engineering education in the U.S. As part of this work, we conducted semi-structured interviews with seven change leaders in engineering education and DEIJ. We asked their perspectives on community of practice as a theory of change and whether it is appropriate for this work. Their responses were coded, revealing 169 codes, some of which advisors agreed upon, and many representing alternative perspectives. Processes such as considering, accepting, asking, and acknowledging are easy to overlook while executing change through mentoring, funding, and doing. The results of this work are helpful for civil and environmental engineering (CEE) faculty members interested in operationalizing change in their classroom and on their campus to meet ABET’s relatively recent DEI criteria, and the process in this study is transferrable to other fields that are also mobilizing transformative practices for integrating DEIJ principles into their curricula.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1186/s40594-020-0202-3
