scholarly journals The hierarchy-of-hypotheses approach: A synthesis method for enhancing theory development in ecology and evolution

2019 ◽  
Author(s):  
Tina Heger ◽  
Carlos Aguilar ◽  
Isabelle Bartram ◽  
Raul Rennó Braga ◽  
Gregory P. Dietl ◽  
...  
Keyword(s):  
Big Data ◽  
Structure Data ◽  
Evolutionary Biology ◽  
Meta Analysis ◽  
Synthesis Method ◽  
Theory Development ◽  
Top Down ◽  
Bottom Up ◽  
Empirical Results ◽  
Develop Theory

In the current era of Big Data, existing synthesis tools (e.g. formal meta-analysis) are useful for handling the deluge of data and information. However, there is a need for complementary tools that help to (i) structure data and information, (ii) closely connect evidence to theory and (iii) further develop theory. We present the hierarchy-of-hypotheses (HoH) approach to address these issues. In an HoH, hypotheses are conceptually and visually structured in a hierarchically nested way, where the lower branches can be directly connected to empirical results. Used as an evidence-driven, bottom-up approach, it can (i) show connections between empirical results, even when derived through diverse approaches; and (ii) indicate under which circumstances hypotheses are applicable. Used as a theory-driven, top-down method, it helps uncover mechanistic components of hypotheses. We offer guidance on how to build an HoH, provide examples from population and evolutionary biology and propose terminological clarifications.

Racial prototypicality cues exacerbate racial bias in pain perception from the bottom up and the top down

2020 ◽  
Author(s):  
Alexis Drain ◽  
Azaadeh Goharzad ◽  
Jennie Qu-Lee ◽  
Jingrun Lin ◽  
Peter Mende-Siedlecki
Keyword(s):  
Pain Perception ◽  
Racial Bias ◽  
Meta Analysis ◽  
Structural Features ◽  
Facial Structure ◽  
Top Down ◽  
Bottom Up ◽  
Race And Gender ◽  
Pain Outcomes ◽  
And Gender

Racial disparities in pain care may stem, in part, from a perceptual source. While perceptual disruptions in recognizing painful expressions on Black faces have been demonstrated under tightly-controlled conditions (e.g., controlling for low-level stimulus differences in luminance and facial structure, using all male stimuli), these effects may be exacerbated by cues to racial prototypicality. Indeed, both bottom-up (e.g., skin tone, facial structure) and top-down (e.g., stereotype associations between race and gender) factors related to racial prototypicality moderate social perception, with some evidence pointing towards deleterious consequences in the domain of health. Here, we assessed whether these factors shape racial bias in pain perception: we examined the effect of racially prototypical features in Experiments 1 and 2 and target gender in a meta-analysis across five additional experiments. Overall, darker skin tones were associated with more stringent pain perception and more conservative treatment, while racially prototypic structural features exacerbated racial bias in pain outcomes. Moreover, target gender reliably moderated the effect of race on pain outcomes: racial biases in both pain perception and treatment were larger for male (versus female) targets. Taken together, these data demonstrate the overall robustness of racial bias in pain perception and its facilitation of gaps in treatment, but also the extent to which these biases are moderated by both bottom-up and top-down factors related to racial prototypicality.

scholarly journals Bottom‐up vs. top‐down effects on terrestrial insect herbivores: a meta‐analysis

2017 ◽  
Vol 21 (1) ◽  
pp. 138-150 ◽  
Author(s):  
Mayra C. Vidal ◽  
Shannon M. Murphy
Keyword(s):  
Meta Analysis ◽  
Insect Herbivores ◽  
Top Down ◽  
Bottom Up ◽  
Terrestrial Insect

scholarly journals From Petty Corruption to Criminal State

Intersections ◽  
2019 ◽  
Vol 5 (2) ◽  
Author(s):  
Bálint Magyar ◽  
Bálint Madlovics
Keyword(s):  
Big Data ◽  
Free Market ◽  
Analytical Framework ◽  
The State ◽  
Top Down ◽  
Bottom Up ◽  
Country Comparison ◽  
State Capture ◽  
Cross Country ◽  
Four Levels

Offering a decent database easily applicable to cross-country comparison, Transparency International’s Corruption Perceptions Index (CPI) has been widely used as a variable for showing the level of corruption. However, surveys of its sources are based on presumptions which mainly apply to bottom-up forms of corruption, namely free market corruption and bottom-up state capture, and therefore it is insufficient for assessing the state of a country plagued by top-down types of the former. We provide an analytical framework that distinguishes four levels of corruption and draws on the experience of the post-communist region. Using this framework to analyze the CPI’s survey questions, we explain why the index provides a blurred picture of the region. ‘Big data’ evidence for top-down corruption in Hungary is also presented, signifying the need for a more refined index.

“Bio to bits”: the Millennium Ecosystem Assessment (MA) as a metaphor for Big Data ecosystem assessment

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sepehr Ghazinoory ◽  
Shohreh Nasri ◽  
Roya Dastranj ◽  
Alfred Sarkissian
Keyword(s):  
Big Data ◽  
User Needs ◽  
Millennium Ecosystem Assessment ◽  
End User ◽  
Drivers Of Change ◽  
Top Down ◽  
Bottom Up ◽  
Content Type ◽  
Ecosystem Assessment ◽  
Data Ecosystem

PurposeBig Data (BD) is not only a quintessential part of many economic activities but also has evolved into a veritable business ecosystem. However, most Big Data ecosystem (BDE) models have a technical, bottom-up focus and mostly lack the capability for a broad socioeconomic analysis. This paper identifies the Millennium Ecosystem Assessment (MA) as a useful, operational framework and uses a metaphorical analogy to adapt it for the BDE. The top-down approach adopted here allows for seeing the big picture of the BD ecosystem. Meeting “end-user needs” is the main objective of the proposed BDE framework.Design/methodology/approachThe methodology of this paper consists of two parts. First, the MA is adapted for the BDE through a metaphorical analogy. Then, to operationalize and validate the proposed framework, it is applied to an emerging BD ecosystem.FindingsIn total, four types of services are offered in the BD ecosystem: provisioning information and products; regulating; cultural and supporting services. Direct and indirect drivers of change impact ecosystem processes such as BD service provision. Based on the assessment results, interventions can be devised to remedy problems, sustain the ecosystem or accelerate growth. The proposed BDE assessment framework is applied to an emerging BDE as an example of operationalization and validation of the proposed BDE framework.Originality/valueThe strengths of the proposed BDE framework is that, in contrast to existing frameworks that are technical and bottom-up, it is constructed top-down by a metaphorical analogy from the proven MA framework. It is a generic framework with the ultimate objective of meeting the “end-user needs” and does not focus on a single sector or firm. Also, the proposed BDE framework is multi-faceted and considers broad socioeconomic issues such as regulating, cultural and supporting services and drivers of change.

scholarly journals Modular and Integrated Systems for Nanoparticle and Microparticle Synthesis—A Review

Biosensors ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 165
Author(s):  
Hongda Lu ◽  
Shi-Yang Tang ◽  
Guolin Yun ◽  
Haiyue Li ◽  
Yuxin Zhang ◽  
...  
Keyword(s):  
Physical Properties ◽  
Materials Science ◽  
Synthesis Method ◽  
Integrated Systems ◽  
Top Down ◽  
Large Space ◽  
Bottom Up ◽  
On Demand ◽  
Complex Operation ◽  
Expensive Equipment

Nanoparticles (NPs) and microparticles (MPs) have been widely used in different areas of research such as materials science, energy, and biotechnology. On-demand synthesis of NPs and MPs with desired chemical and physical properties is essential for different applications. However, most of the conventional methods for producing NPs/MPs require bulky and expensive equipment, which occupies large space and generally need complex operation with dedicated expertise and labour. These limitations hinder inexperienced researchers to harness the advantages of NPs and MPs in their fields of research. When problems individual researchers accumulate, the overall interdisciplinary innovations for unleashing a wider range of directions are undermined. In recent years, modular and integrated systems are developed for resolving the ongoing dilemma. In this review, we focus on the development of modular and integrated systems that assist the production of NPs and MPs. We categorise these systems into two major groups: systems for the synthesis of (1) NPs and (2) MPs; systems for producing NPs are further divided into two sections based on top-down and bottom-up approaches. The mechanisms of each synthesis method are explained, and the properties of produced NPs/MPs are compared. Finally, we discuss existing challenges and outline the potentials for the development of modular and integrated systems.

scholarly journals Synthesis of graphene: Potential carbon precursors and approaches

2020 ◽  
Vol 9 (1) ◽  
pp. 1284-1314
Author(s):  
Yuxin Yan ◽  
Fathima Zahra Nashath ◽  
Sharon Chen ◽  
Sivakumar Manickam ◽  
Siew Shee Lim ◽  
...  
Keyword(s):  
Large Scale ◽  
Synthesis Method ◽  
Chemical Vapour ◽  
Synthesis Methods ◽  
Top Down ◽  
Bottom Up ◽  
Graphene Synthesis ◽  
Common Precursor ◽  
Wide Range ◽  
Fit For Purpose

Abstract Graphene is an advanced carbon functional material with inherent unique properties that make it suitable for a wide range of applications. It can be synthesized through either the top–down approach involving delamination of graphitic materials or the bottom–up approach involving graphene assembly from smaller building units. Common top–down approaches are exfoliation and reduction while bottom–up approaches include chemical vapour deposition, epitaxial growth, and pyrolysis. A range of materials have been successfully used as precursors in various synthesis methods to derive graphene. This review analyses and discusses the suitability of conventional, plant- and animal-derived, chemical, and fossil precursors for graphene synthesis. Together with its associated technical feasibility and economic and environmental impacts, the quality of resultant graphene is critically assessed and discussed. After evaluating the parameters mentioned above, the most appropriate synthesis method for each precursor is identified. While graphite is currently the most common precursor for graphene synthesis, several other precursors have the potential to synthesize graphene of comparable, if not better, quality and yield. Thus, this review provides an overview and insights into identifying the potential of various carbon precursors for large-scale and commercial production of fit-for-purpose graphene for specific applications.

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