scholarly journals A Comparative Analysis of Visual Encoding Models Based on Classification and Segmentation Task-Driven CNNs

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Ziya Yu ◽  
Chi Zhang ◽  
Linyuan Wang ◽  
Li Tong ◽  
Bin Yan
Keyword(s):  
Comparative Analysis ◽  
Visual Processing ◽  
Visual Stimulation ◽  
Matching Pursuit ◽  
Linear Mapping ◽  
Human Information Processing ◽  
Model Based ◽  
Visual Encoding ◽  
Segmentation Task ◽  
The Impact

Nowadays, visual encoding models use convolution neural networks (CNNs) with outstanding performance in computer vision to simulate the process of human information processing. However, the prediction performances of encoding models will have differences based on different networks driven by different tasks. Here, the impact of network tasks on encoding models is studied. Using functional magnetic resonance imaging (fMRI) data, the features of natural visual stimulation are extracted using a segmentation network (FCN32s) and a classification network (VGG16) with different visual tasks but similar network structure. Then, using three sets of features, i.e., segmentation, classification, and fused features, the regularized orthogonal matching pursuit (ROMP) method is used to establish the linear mapping from features to voxel responses. The analysis results indicate that encoding models based on networks performing different tasks can effectively but differently predict stimulus-induced responses measured by fMRI. The prediction accuracy of the encoding model based on VGG is found to be significantly better than that of the model based on FCN in most voxels but similar to that of fused features. The comparative analysis demonstrates that the CNN performing the classification task is more similar to human visual processing than that performing the segmentation task.

scholarly journals Assessing functional reorganization in visual cortex with simulated retinal lesions

2021 ◽  
Author(s):  
Holly D. H. Brown ◽  
André D. Gouws ◽  
Richard J. W. Vernon ◽  
Samuel J. D. Lawrence ◽  
Gemma Donnelly ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Visual Processing ◽  
Vision Loss ◽  
Visual Stimulation ◽  
Retinal Lesions ◽  
Central Vision Loss ◽  
Central Disk ◽  
Mean Luminance ◽  
Cortical Regions ◽  
The Impact

AbstractMacular degeneration (MD) causes central vision loss, removing input to corresponding representations in the primary visual cortex. There is disagreement concerning whether the cortical regions deprived of input can remain responsive, and the source of reported cortical responses is still debated. To simulate MD in controls, normally sighted participants viewed a bright central disk to adapt the retina, creating a transient ‘retinal lesion’ during a functional MRI experiment. Participants viewed blocks of faces, scrambled faces and uniform grey stimuli, either passively or whilst performing a one-back task. To assess the impact of the simulated lesion, participants repeated the paradigm using a more conventional mean luminance simulated scotoma without adaptation. Our results suggest our attempt to create a more realistic simulation of a lesion did not impact on responses in the representation of the simulated lesion. While most participants showed no evidence of stimulus-driven activation within the lesion representation, a few individuals (22%) exhibited responses similar to a participant with juvenile MD who completed the same paradigm (without adaptation). Reliability analysis showed that responses in the representation of the lesion were generally consistent irrespective of whether positive or negative. We provide some evidence that peripheral visual stimulation can also produce responses in central representations in controls while performing a task. This suggests that the ‘signature of reorganization of visual processing’, is not found solely in patients with retinal lesions, consistent with the idea that activity may be driven by unmasked top–down feedback.

scholarly journals Assessing functional reorganization in visual cortex with simulated retinal lesions

2021 ◽  
Author(s):  
Holly D. H. Brown ◽  
André D. Gouws ◽  
Richard J. W. Vernon ◽  
Samuel J. D. Lawrence ◽  
Gemma Donnelly ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Visual Processing ◽  
Vision Loss ◽  
Visual Stimulation ◽  
Retinal Lesions ◽  
Central Vision Loss ◽  
Central Disk ◽  
Mean Luminance ◽  
Cortical Regions ◽  
The Impact

Abstract Macular degeneration (MD) causes central vision loss, removing input to corresponding representations in the primary visual cortex. There is disagreement concerning whether the cortical regions deprived of input can remain responsive, and the source of reported cortical responses is still debated. To simulate MD in controls, normally sighted participants viewed a bright central disk to adapt the retina, creating a transient ‘retinal lesion’ during a functional MRI experiment. Participants viewed blocks of faces, scrambled faces and uniform gray stimuli, either passively or whilst performing a one-back task. To assess the impact of the simulated lesion, participants repeated the paradigm using a more conventional mean luminance simulated scotoma without adaptation. Our results suggest our attempt to create a more realistic simulation of a lesion did not impact on responses in the representation of the simulated lesion. While most participants showed no evidence of stimulus-driven activation within the lesion representation, a few individuals (22%) exhibited responses similar to a participant with juvenile MD who completed the same paradigm (without adaptation). Reliability analysis showed that responses in the representation of the lesion were generally consistent irrespective of whether positive or negative. We provide some evidence that peripheral visual stimulation can also produce responses in central representations in controls while performing a task. This suggests that the ‘signature of reorganization of visual processing’, is not found solely in patients with retinal lesions, consistent with the idea that activity may be driven by unmasked top-down feedback.

Corruption as “one‑stop‑shop”: theory and empirical analysis

2018 ◽  
pp. 32-51
Author(s):  
R. Yu. Kochnev ◽  
L. I. Polishchuk ◽  
A. Yu. Rubin
Keyword(s):  
Comparative Analysis ◽  
Business Environment ◽  
Enterprise Performance ◽  
Double Jeopardy ◽  
One Stop ◽  
The Commons ◽  
Public Production ◽  
Performance Project ◽  
The Impact ◽  
Sector Theory

We present the comparative analysis of the impact of centralized and decentralized corruption for private sector. Theory and empirical evidence point out to a “double jeopardy” of decentralized corruption which increases the burden of corruption upon private firms and weakens the incentives of bureaucracy to provide public production inputs, such as infrastructure. These outcomes are produced by simultaneous free-riding and the tragedy of the commons effects. The empirical part of the paper utilizes data of the Business Environment and Enterprise Performance project.

Assessment of small businesses activities in Ukraine

2019 ◽  
pp. 40-47
Author(s):  
Igor Ponomarenko ◽  
Kateryna Volovnenko
Keyword(s):  
Comparative Analysis ◽  
Statistical Analysis ◽  
Small Business ◽  
Small Businesses ◽  
Government Agencies ◽  
Small Enterprises ◽  
The Subject ◽  
Business Entities ◽  
The Impact ◽  
Micro Enterprises

The subject of the research is a set of approaches to the statistical analysis ofthe activities of small business entities in Ukraine, including micro-enterprises. The purpose of writing this article is to study of the features of functioningof small business entities in Ukraine. Methodology. The research methodology isto use a system-structural and comparative analysis (to study the change in thenumber of small enterprises by major components); monographic (when studyingmethods of statistical analysis of small businesses); economic analysis (when assessing the impact of small business entities on socio-economic phenomena andprocesses in Ukraine). The scientific novelty consists to determine the features ofthe functioning of small businesses in Ukraine in modern conditions. The influenceof the activities of the main socio-economic and political indicators on the activities of small enterprises in recent periods of time has been identified. It has beenestablished that there is flexibility in the development of strategies by small businesses in conditions of significant competition, which makes it possible to quicklyrespond to changing situations in specific markets. Conclusions. The use of acomprehensive statistical analysis of small businesses functioning in Ukraine willallow government agencies to develop a set of measures to optimize the activitiesof these enterprises, which ultimately will positively affect the strengthening oftheir competitiveness and will contribute to the growth of the national economicsystem.

Unemployment as an indicator of economic security in the employment sector: A regional dimension

2020 ◽  
Vol 16 (4) ◽  
pp. 715-729
Author(s):  
T.N. Savina
Keyword(s):  
Comparative Analysis ◽  
Age Groups ◽  
National Development ◽  
Federal District ◽  
Economic Security ◽  
Employment Policy ◽  
Multivariate Statistical ◽  
Band Theory ◽  
The Republic ◽  
The Impact

Subject. To achieve a high level of economic security is a key priority of national development. Employment reveals one of the most important aspects of social development of the individual that is associated with his or her needs satisfaction in the sphere of employment and is boon to economic security. Objectives. The purpose of the study is to show the impact of unemployment on economic security in employment. Methods. I apply such scientific methods as dialectical, historical and logical unity, structural and functional analysis, traditional techniques of economic analysis and synthesis. The methods of multivariate statistical and comparative analysis serve as a methodological basis of the study. To determine the indicator of unemployment, I use the band theory. Results. I underpin the growing role of employment in ensuring economic security. The paper presents a comprehensive assessment of the unemployment status and a comparative analysis of the indicator in the Republic of Mordovia, the Volga Federal District, and the Russian Federation as a whole. I identify trends in the average duration of unemployment, show the distribution of unemployed by level of education and age groups. Conclusions. The average annual unemployment rate in the Republic of Mordovia is lower than in Russia and the Volga Federal District. The findings may be useful for public authorities to substantiate their employment policy at both macro- and meso-levels, for designing programs and strategies for socio-economic development of regions and the social security doctrine, as well as in practical activities of employment services.

Directions of Accounting Environmental Factors for Forecasting Formation of Agroecosystems

2020 ◽  
pp. 31-35
Author(s):  
L.Z. Khalishkhova ◽  
◽  
A. Kh. Temrokova ◽  
I.R. Guchapsheva ◽  
K.A. Bogаtyreva ◽  
...  
Keyword(s):  
Sustainable Development ◽  
Comparative Analysis ◽  
Environmental Factors ◽  
Environmental Safety ◽  
Logical Analysis ◽  
Management Decisions ◽  
The Sustainable Development ◽  
The Impact

Ensuring the sustainable development of agroecosystems requires research into the justification of the impact of environmental factors on the formation of territorial agroecosystems and identifies ways to take them into account in order to justify management decisions and ensure environmental safety. The main goal of the research within the article is to identify the most significant environmental factors in predicting the formation of agroecosystems. Provisions are devoted to the study of the laws governing the functioning of agroecosystems in order to increase their stability. The methods of comparative analysis, generalization, abstraction, logical analysis are applied. A number of provisions are formulated regarding ways to account for the influence of factors on the formation of key elements of agroecosystems.

Features and tendencies of budgetary provision of Zaporizhzhya region development in the conditions of budget decentralization

2019 ◽  
pp. 88-97
Author(s):  
Iryna Storonyanska ◽  
Liliya Benovska
Keyword(s):  
Comparative Analysis ◽  
Regional Development ◽  
State Budget ◽  
Regional Center ◽  
The Social ◽  
Graphical Visualization ◽  
Social And Economic Development ◽  
Decentralization Reform ◽  
Regional Development Strategies ◽  
The Impact

The purpose of the article is to study trends and identify problems of budgetary provision of the development of Zaporizhzhia region in the context of budgetary decentralization reform. Methods of systematic and comparative analysis, graphical visualization, generalization and statistical methods were used for the study. The article examines the impact of decentralization reform on the financial provision of social and economic development of administrative and territorial units of Zaporizhzhia region. The comparative analysis of the budgetary provision of the development of Zaporizhzhya region and other regions of the Central region is conducted. The article describes the trends and problems of Zaporizhzhya region development. The following positive trends were revealed: increase of revenues to local budgets of the region; reduction of transfer dependence of the region on the state budget; formation of high-taxation CTCs. The negative tendencies of development were: increase of differentiation of financial provision of the development of the regional center and other administrative and territorial units, reduction of the growth rate of revenues to the development budget of Zaporizhzhia region. Attention is drawn to the fact that under the conditions of decentralization reform and administrative and territorial reform, consolidated territorial communities are actively being formed in the Zaporizhzhya region, most of them with high financial capacity, which testifies to the high potential of regional development. The article analyzes the regional target programs of Zaporizhzhia region and clarifies the possibilities of their integration with the Action Plans for implementation of the Regional Development Strategies. The dominance of the social component over the development of regional target programs and low level of implementation of a number of programs are emphasized.

scholarly journals Assessing the Risk of Democratic Reversal in the United States: A Reply to Kurt Weyland

2021 ◽  
pp. 1-6
Author(s):  
Matias López ◽  
Juan Pablo Luna
Keyword(s):  
United States ◽  
Comparative Analysis ◽  
Boolean Algebra ◽  
Qualitative Comparative Analysis ◽  
The United States ◽  
American Democracy ◽  
Institutional Dynamics ◽  
The Public ◽  
Original Analysis ◽  
The Impact

ABSTRACT By replying to Kurt Weyland’s (2020) comparative study of populism, we revisit optimistic perspectives on the health of American democracy in light of existing evidence. Relying on a set-theoretical approach, Weyland concludes that populists succeed in subverting democracy only when institutional weakness and conjunctural misfortune are observed jointly in a polity, thereby conferring on the United States immunity to democratic reversal. We challenge this conclusion on two grounds. First, we argue that the focus on institutional dynamics neglects the impact of the structural conditions in which institutions are embedded, such as inequality, racial cleavages, and changing political attitudes among the public. Second, we claim that endogeneity, coding errors, and the (mis)use of Boolean algebra raise questions about the accuracy of the analysis and its conclusions. Although we are skeptical of crisp-set Qualitative Comparative Analysis as an adequate modeling choice, we replicate the original analysis and find that the paths toward democratic backsliding and continuity are both potentially compatible with the United States.

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