A note on the Mackey-star topology on a dual Banach space

[EN] By using a result in Kirk (Pac J Math 45:543 554, 1973), we show that there are separable Banach spaces such that their dual spaces, endowed with the Mackey-star topology, are not analytic. This solves a question raised in Kakol et al. (Descriptive topology in selected topics of functional analysis, Springer, 2011), and in Kakol and López-Pellicer (RACSAM 105:39 70, 2011).A. J. Guirao is Supported in part by MICINN and FEDER (Project MTM2008-05396), by Fundación Séneca (Project 08848/PI/08), by Generalitat Valenciana (GV/2010/036), and by Universitat Politècnica de València (project PAID-06-09-2829). V. Montesinos is Supported in part by Project MICINN MTM2011-22417, Generalitat Valenciana (GV/2010/036), and by Universitat Politècnica de València (Project PAID-06-09-2829).Guirao Sánchez, AJ.; Montesinos Santalucia, V. (2015). A note on the Mackey-star topology on a dual Banach space. Revista de la Real Academia de Ciencias Exactas Físicas y Naturales Serie A Matemáticas. 109(2):417-418. https://doi.org/10.1007/s13398-014-0192-4S4174181092Fabian, M., Montesinos, V., Zizler, V.: On weak compactness in $$L_1$$ L 1 spaces. Rocky Mt. J. Math. 39, 1885–1893 (2009)Grothendieck, A.: Topological vector spaces, Translated from the French by Orlando Chaljub. Gordon and Breach Science publishers, New York (1973)Kąkol, J., López-Pellicer, M.: On realcompact topological vector spaces. RACSAM 105, 39–70 (2011)Kąkol, J., Kubiś, W., López-Pellicer, M.: Descriptive Topology in Selected Topics of Functional Analysis. In: Developments in Mathematics, vol. 24. Springer, New York (2011)Kirk, R.B.: A note on the Mackey topology for $$(C^b(X)^*, C^b(X))$$ ( C b ( X ) ∗ , C b ( X ) ) . Pac. J. Math. 45(2), 543–554 (1973)Köthe, G.: Topological vector spaces I, Translated by D.J.H. Garling, Die Grundlehren der mathematischen Wissenschaften in Einzeldarstellungen, Band 159, 2nd edn. Springer, New York (1969)Schlüchtermann, G., Wheeler, R.F.: On strongly WCG Banach spaces. Math. Z. 199, 387–398 (1988

The Top-Dog Index: A New Measurement for the Demand Consistency of the Size Distribution in Pre-Pack Orders for a Fashion Discounter with Many Small Branches

We propose the new Top-Dog-Index, a measure for the branch-dependent historic deviation of the supply data of apparel sizes from the sales data of a fashion discounter. A common approach is to estimate demand for sizes directly from the sales data. This approach may yield information for the demand for sizes if aggregated over all branches and products. However, as we will show in a real-world business case, this direct approach is in general not capable to provide information about each branch's individual demand for sizes: the supply per branch is so small that either the number of sales is statistically too small for a good estimate (early measurement) or there will be too much unsatisfied demand neglected in the sales data (late measurement). Moreover, in our real-world data we could not verify any of the demand distribution assumptions suggested in the literature. Our approach cannot estimate the demand for sizes directly. It can, however, individually measure for each branch the scarcest and the amplest sizes, aggregated over all products. This measurement can iteratively be used to adapt the size distributions in the pre-pack orders for the future. A real-world blind study shows the potential of this distribution free heuristic optimization approach: The gross yield measured in percent of gross value was almost one percentage point higher in the test-group branches than in the control-group branches.Comment: 22 pages, 15 figure

On realcompact topological vector spaces

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NN201 2740 33 and for the both authors by the project MTM2008-01502 of the Spanish Ministry of Science and Innovation.Kakol, JM.; López Pellicer, M. (2011). On realcompact topological vector spaces. Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas. 105(1):39-70. https://doi.org/10.1007/s13398-011-0003-0S39701051Argyros S., Mercourakis S.: On weakly Lindelöf Banach spaces. Rocky Mountain J. Math. 23(2), 395–446 (1993). doi: 10.1216/rmjm/1181072569Arkhangel’skii, A. V.: Topological Function Spaces, Mathematics and its Applications, vol. 78, Kluwer, Dordrecht (1992)Batt J., Hiermeyer W.: On compactness in L p (μ, X) in the weak topology and in the topology σ(L p (μ, X), L p (μ,X′)). Math. Z. 182, 409–423 (1983)Baumgartner J.E., van Douwen E.K.: Strong realcompactness and weakly measurable cardinals. Topol. 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