DAM - Artículoshttp://hdl.handle.net/10481/313582019-07-21T16:02:42Z2019-07-21T16:02:42ZEstimation of Housing Price Variations Using Spatio-Temporal DataChica Olmo, JorgeCano-Guervos, RafaelChica Rivas, Mariohttp://hdl.handle.net/10481/556542019-05-08T07:50:44ZEstimation of Housing Price Variations Using Spatio-Temporal Data
Chica Olmo, Jorge; Cano-Guervos, Rafael; Chica Rivas, Mario
This paper proposes a hedonic regression model to estimate housing prices and the spatial
variability of prices overmultiple years. Using themodel, maps are obtained that represent areas of the
city where there have been positive or negative changes in housing prices. The regression-cokriging
(RCK)method is used to predict housing prices. The results are compared to the cokrigingwith external
drift (CKED) model, also known as universal cokriging (UCK). To apply the model, heterotopic data
of homes for sale at different moments in time are used. The procedure is applied to predict the spatial
variability of housing prices in multi-years and to obtain isovalue maps of these variations for the city
of Granada, Spain. The research is useful for the fields of urban studies, economics, real estate, real
estate valuations, urban planning, and for scholars.
A family of singular functions and its relation to harmonic fractal analysis and fuzzy logicAmo, Enrique deDáiz Carrillo, ManuelFernández Sánchez, Juanhttp://hdl.handle.net/10481/451642018-09-08T07:16:47ZA family of singular functions and its relation to harmonic fractal analysis and fuzzy logic
Amo, Enrique de; Dáiz Carrillo, Manuel; Fernández Sánchez, Juan
We study a parameterized family of singular functions which appears in a paper by H. Okamoto and M. Wunsch (2007). Various properties are revisited from the viewpoint of fractal geometry and probabilistic techniques. Hausdorff dimensions are calculated for several sets related to these functions, and new properties close to fractal analysis and strong negations are explored.
Čebyšëv subspaces of JBW ∗ -triplesJamjoom, Fatmah B.Peralta, Antonio MiguelSiddiqui, Akhlaq A.Tahlawi, Haifa A.http://hdl.handle.net/10481/385532018-09-08T07:16:51ZČebyšëv subspaces of JBW ∗ -triples
Jamjoom, Fatmah B.; Peralta, Antonio Miguel; Siddiqui, Akhlaq A.; Tahlawi, Haifa A.
We describe the one-dimensional Čebyšëv subspaces of a JBW ∗ -triple M by showing that for a non-zero element x in M, Cx is a Čebyšëv subspace of M if and only if x is a Brown-Pedersen quasi-invertible element in M. We study the Čebyšëv JBW ∗ -subtriples of a JBW ∗ -triple M. We prove that for each non-zero Čebyšëv JBW ∗ -subtriple N of M, exactly one of the following statements holds:
(a) N is a rank-one JBW ∗ -triple with dim(N)≥2 (i.e., a complex Hilbert space regarded as a type 1 Cartan factor). Moreover, N may be a closed subspace of arbitrary dimension and M may have arbitrary rank;
(b) N=Ce, where e is a complete tripotent in M;
(c) N and M have rank two, but N may have arbitrary dimension ≥2;
(d) N has rank greater than or equal to three, and N=M.
We also provide new examples of Čebyšëv subspaces of classic Banach spaces in connection with ternary rings of operators.
Dynamics, Operator Theory, and Infinite HolomorphyPeris, AlfredMaestre, ManuelMartín Suárez, MiguelChoi, Yun-Sunghttp://hdl.handle.net/10481/349162018-09-08T07:16:49ZDynamics, Operator Theory, and Infinite Holomorphy
Peris, Alfred; Maestre, Manuel; Martín Suárez, Miguel; Choi, Yun-Sung
The works on linear dynamics in the last two decades show that many, even quite natural, linear dynamical systems exhibit wild behaviour. Linear chaos and hypercyclicity have been at the crossroads of several areas of mathematics. More recently, fascinating new connections have started to be explored: operators on spaces of analytic functions, semigroups and applications to partial differential equations, complex dynamics, and ergodic theory.
Related aspects of functional analysis are the study of linear operators on Banach spaces by using geometric, topological, and algebraic techniques, the works on the geometry of Banach spaces and Banach algebras, and the study of the geometry of a Banach space via the behaviour of some of its operators.
In recent years some aspects of the theory of infinite-dimensional complex analysis have attracted the attention of several researchers. One is in the general field of Banach and Fréchet algebras and Banach spaces of polynomial and holomorphic functions. Another is in a deep connection with the theory of one and several complex variables as Dirichlet series in one variable, Bohr radii in several variables, Bohnenblust-Hille constants, Sidon constants, domains of convergence, and so forth.
This special issue shows some new advances in the topics shortly described above.
The multiplicative spectrum and the uniqueness of the complete norm topologyMarcos Sánchez, Juan CarlosVelasco Collado, María Victoriahttp://hdl.handle.net/10481/335432018-09-08T07:16:50ZThe multiplicative spectrum and the uniqueness of the complete norm topology
Marcos Sánchez, Juan Carlos; Velasco Collado, María Victoria
We define the spectrum of an element a in a non-associative algebra A according to a classical notion of invertibility (a is invertible if the multiplication operators La and Ra are bijective). Around this notion of spectrum, we develop a basic theoretical support for a non-associative spectral theory. Thus we prove some classical theorems of automatic continuity free of the requirement of associativity. In particular, we show the uniqueness of the complete norm topology of m-semisimple algebras, obtaining as a corollary of this result a well-known theorem of Barry E. Johnson (1967). The celebrated result of C.E. Rickart (1960) about the continuity of dense-range homomorphisms is also studied in the non-associative framework. Finally, because non-associative algebras are very suitable models in genetics, we provide here a hint of how to apply this approach in that context, by showing that every homomorphism from a complete normed algebra onto a particular type of evolution algebra is automatically continuous.