On the total outer-connected domination in graphs

A set S of vertices of a graph G is a total outer-connected dominating set if every vertex in V(G) is adjacent to some vertex in S and the subgraph induced by V?S is connected. The total outer-connected domination number γ _toc (G) is the minimum size of such a set. We give some properties and bounds for γ _toc in general graphs and in trees. For graphs of order n, diameter 2 and minimum degree at least 3, we show that $\gamma_{toc}(G)\le \frac{2n-2}{3}$ and we determine the extremal graphs.     

Comment “On the role of data,statistics and decisions in a pandemic” by Jahn et al.

AStA Advances in Statistical Analysis - We comment the paper by Jahn et al. (On the role of data, statistics and decisions in a pandemic, 2022).     

Customer satisfaction: Cost driver or value driver? Empirical evidence from the financial services industry

We investigate the relation between customer satisfaction, customer servicing costs, and customer value in a financial services firm. We find that customer satisfaction is positively associated with future customer servicing costs, as well as with customer value. The relation between customer satisfaction and customer value appears non-linear; higher customer satisfaction appears to have a higher return for the most profitable customer segments. Our findings indicate that customer satisfaction is a value driver; however, customer satisfaction is not cost-free and managers have to consider the costs, as well as the benefits, of increasing customer satisfaction.