This paper constructs a unique cohort data set to study the changes since 1960 in the share of Americans' resources that are annuitized. Understanding these changes is important because the larger this share, the more cohorts are likely to consume and the less they are likely to bequeath. Hence, the degree of annuitization affects national saving as well as the transmission of inequality over t...

We use individual and aggregate data to ask how the Internet is changing the ideological segregation of the American electorate. Focusing on online news consumption, offline news consumption, and face-to-face social interactions, we define ideological segregation in each domain using standard indices from the literatureonracial segregation. Wefindthat ideological segregationofonlinenews consump...

Marketers have been interested in diffusion of new products since Bass (1969). One of the main objectives inherent in diffusion studies is to explain the sales pattern of new products over time. Many factors can influence sales patterns including firm’s marketing strategies, consumer characteristics in the market, consumer expectations of utility from the products, value of the product in conju...

This two-part state-of-the-art overview on aggregation theory summarizes the essential information concerning aggregation issues. An overview of aggregation properties is given, including the basic classification on aggregation functions. In this first part, the stress is put on means, i.e., averaging aggregation functions, both with fixed arity (n-ary means) and with multiple arities (extended...

Logic-based preference representation languages are promising for expressing preferences over combinatorial domains. Sets of weighted formulas, called goalbases, can be used to define several such languages. How goalbases are translated into utility functions—that is, by what aggregation function this is done—is a crucial component of this type of language. In this paper, we consider the proper...

Models of movie theatre demand have tended to employ aggregate data and focus on price and income as key variables. Surprisingly, the effect of travel time and multiplexes has not, hitherto, been formally investigated. This study does so using national survey data. Following developments in the environmental economics literature, we present estimates of individual travel cost models for multipl...

This paper deals with the characterization of some classes of aggregation functions often used in multicriteria decision making problems. The common properties involved in these characterizations are “increasing monotonicity” and “stability for positive linear transformations”. Additional algebraic properties related to associativity allow to completely specify the functions.

We investigate the problem of combining or aggregating several color values given in coding scheme RGB. For this reason, we study the problem of averaging values on lattices, and in particular on discrete product lattices. We study the arithemtic mean and the median on product lattices. We apply these aggregation functions in image reduction and we present a new algorithm based on the minimizat...

Signcryption schemes provide an efficient messaging system for data that needs to be sent with data confidentiality, data integrity and data origin authentication. However, the bandwidth overhead for the use of signcryption in a network in which a large number of messages need to be sent may be high. Motivated by aggregate signature schemes, we propose the concept of an aggregate signcryption s...