Purpose
– Reflecting the moral theorisation of bribery as a negative phenomenon, bribery has been widely shown to have a deleterious impact at the national level on economic development and growth. ...The purpose of this paper is to evaluate whether it is also the case at the firm level that bribery has negative impacts on firm performance. Until now, the few studies conducted in individual nations and regions have produced mixed results. Here, therefore, a more comprehensive evaluation of the relationship between bribery and firm performance is undertaken across the developing world.
Design/methodology/approach
– To do so, World Bank Enterprise Survey data on 106,805 enterprises across 132 developing countries is used to provide a firm-level analysis of the relationship between bribery and firm performance.
Findings
– The finding is that bribery enhances firm performance. Firms asserting that it is necessary for enterprises like theirs to give gifts or payments to public officials in order to get things done have 13.9 per cent higher average annual sales growth rates and 48 per cent higher annual productivity growth rates, after controlling for other determinants of firm performance.
Practical implications
– Given that engaging in bribery at the firm level results in higher firm performance, despite bribery having an overall detrimental negative impact at the country level, public authorities will need to develop measures to alter not only the cost-benefit ratio confronting individual enterprises but also the institutional deficiencies that result in the prevalence of bribery.
Originality/value
– This is the first firm-level evaluation of the relationship between bribery and firm performance across the developing world.
The aim of this paper is to obtain new inequalities for a large family of topological indices restricted to unicyclic graphs and to characterize the set of extremal unicyclic graphs with respect to ...them. This family includes variable first Zagreb, variable sum exdeg, multiplicative second Zagreb and Narumi-Katayama indices. Our main results provide upper and lower bounds for these topological indices on unicyclic graphs, fixing or not the maximum degree or the number of pendant vertices.
•We use Schur convexity to study, in a generalized way, upper and lower bounds for topological indices on unicyclic graphs.•We give sharp upper and lower bounds for variable first Zagreb index on unicyclic graphs.•We give sharp upper and lower bounds for variable sum exdeg index on unicyclic graphs.•We give sharp upper and lower bounds for the Narumi-Katayama indices on unicyclic graphs.
Parabolicity and Cheeger’s constant on graphs Martínez-Pérez, Álvaro; Rodríguez, José M.
Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A, Matemáticas,
10/2024, Letnik:
118, Številka:
4
Journal Article
Recenzirano
Herein we study
p
-parabolicity on graphs. We prove that if a uniform graph satisfies the (Cheeger) isoperimetric inequality, then it is non-
p
-parabolic for every
1
<
p
<
∞
. Moreover, we give ...sufficient conditions for a uniform graph to be non-parabolic and to be
p
-parabolic for every
1
<
p
<
∞
.
To evaluate critically the assumption that consumers participating in cash-in-hand transactions are rational economic actors simply seeking a lower price, evidence from 26,659 interviews conducted in ...27 European Union member states in 2007 is reported. This reveals that a lower price is the sole reason for just 44% of all informal economy purchases, one of several reasons for 28% of such purchases and not a reason in 28% of cases. A multinomial logit regression analysis reveals how the reasons for cash-in-hand purchases vary across populations. The implications for explaining the cash-in-hand consumer culture and policy are then explored.
A celebrated theorem of Kanai states that quasi-isometries preserve isoperimetric inequalities between uniform Riemannian manifolds (with positive injectivity radius) and graphs. Our main result ...states that we can study the (Cheeger) isoperimetric inequality in a Riemann surface by using a graph related to it, even if the surface has injectivity radius zero (this graph is inspired in Kanai’s graph, but it is different from it). We also present an application relating Gromov boundary and isoperimetric inequality.
Kanai proved that quasi-isometries between Riemannian manifolds with bounded geometry preserve many global properties, including the existence of Green’s function, i.e., non-parabolicity. However, ...Kanai’s hypotheses are too restrictive. Herein we prove the stability of
p
-parabolicity (with
1
<
p
<
∞
) by quasi-isometries between Riemannian manifolds under weaker assumptions. Also, we obtain some results on the
p
-parabolicity of graphs and trees; in particular, we characterize
p
-parabolicity for a large class of trees.
We study in this paper the relationship of isoperimetric inequality and hyperbolicity for graphs and Riemannian manifolds. We obtain a characterization of graphs and Riemannian manifolds (with ...bounded local geometry) satisfying the (Cheeger) isoperimetric inequality, in terms of their Gromov boundary, improving similar results from a previous work. In particular, we prove that having a pole is a necessary condition to have isoperimetric inequality and, therefore, it can be removed as hypothesis.
Topological indices are useful for predicting the physicochemical behavior of chemical compounds. A main problem in this topic is finding good bounds for the indices, usually when some parameters of ...the graph are known. The aim of this paper is to use a unified approach in order to obtain several new inequalities for a wide family of topological indices restricted to trees and to characterize the corresponding extremal trees. The main results give upper and lower bounds for a large class of topological indices on trees, fixing or not the maximum degree. This class includes the first variable Zagreb, the Narumi–Katayama, the modified Narumi–Katayama and the Wiener index.
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