Location and reliability problems on a line: Impact of objectives and correlated failures on optimal location patterns

In this paper we study a class of locations models where facilities are not perfectly reliable and failures may be correlated. We analyze problems with Median and Center objectives under complete and incomplete customer information regarding the state of facilities. The goal is to understand how failure probabilities, correlations, availability of information, and problem objective affect the optimal location patterns. In particular, we want to find analytical confirmations for location patterns observed in numerical experiments with network location models. To derive closed-form analytical results the analysis is restricted to a simple (yet classic) setting: a 2-facility problem on a unit segment, with customer demand distributed uniformly over the segment (results can be extended to other demand distributions as well). We derive explicit expressions for facility trajectories as functions of model parameters, obtaining a number of managerial insights. In addition we provide the decomposition of the optimal cost into the closed form components corresponding to the cost of travel, the cost of facility unreliability and the cost of incomplete information. Most of the theoretical insights are confirmed via numerical experiments for models with larger (3–5) number of facilities.     

The Political Configuration of Historical Narrative: The Case of Kazakhstan

ABSTRACT

As time has progressed, Russia has shed the historical legacy of the Soviet era. The same process is going on in Central Asia. The obliteration of the Soviet historical legacy reflects the dying out of the memories of the Soviet Union and the very fact that all these countries had been parts of one state in the not-so-distant past. At the same time, some of these states started to engage in bitter rivalry. The historical legacies were adjusted to new realities. Here, two models compete: one could be called “Turkic” and the other “Iranian.” The “Turkic” model implies that Turkic people are truly autokthonous and have lived in Central Asia since the Bronze Age, and that Iranians/Indo-Europeans are newcomers, without much legitimacy. The “Iranian” model implies that it is Iranians/Indo-Europeans who are truly autokthonous people of Central Asia, and creators of the ancient culture. At the same time, Turkic people are nothing but destructive brutes. Meanwhile, China increasingly fills the discursive and geopolitical vacuum.     

Wealth transfer receipt and later life wealth

Wealth ownership is highly concentrated in the U.S. and this inequality may be reproduced in subsequent generations through wealth transfers. Yet we do not know how households respond to the receipt of a wealth transfer and whether time amplifies the initial benefit of a wealth transfer. Using the Survey of Consumer Finances, we test whether wealth transfer recipients gain an advantage that cumulates with time. We find that the positive association between transfer amount and present net worth weakens as time elapsed since transfer receipt increases. The larger the wealth transfer, the more its association with net worth is diminished by time since transfer receipt. Though wealth transfers provide recipients with a significant initial advantage, households appear to adapt to wealth transfer receipt by some combination of reduced savings and increased consumption. We demonstrate an association between receiving a larger wealth transfer and one type of increased consumption, gift-giving.     

Locating Facilities in the Presence of Disruptions and Incomplete Information*

In this article, we analyze a location model where facilities may be subject to disruptions. Customers do not have advance information about whether a given facility is operational or not, and thus may have to visit several facilities before finding an operational one. The objective is to locate a set of facilities to minimize the total expected cost of customer travel. We decompose the total cost into travel, reliability, and information components. This decomposition allows us to put a value on the advance information about the states of facilities and compare it to the reliability and travel cost components, which allows a decision maker to evaluate which part of the system would benefit the most from improvements. The structure of optimal solutions is analyzed, with two interesting effects identified: facility centralization and co‐location; both effects appear to be stronger than in the complete information case, where the status of each facility is known in advance.