Explainer: Bad housing supply assumptions

Glaeser and Gyourko (2003) (G&G) famously argued that if the marginal cost of a square metre of housing lot land is less than the average cost, this is evidence of a price effect from “artificial” supply constraints. They call this price gap a “regulatory tax”, but it is also known as a “zoning effect” or “zoning tax”. Their logic has been relied upon by hundreds of other studies and in numerous replications of their approach, including by economists from the Reserve Bank of Australia, whose results were widely publicised (Kendall and Tulip, 2018). However, the economic assumptions behind G&G’s approach are implausible. Although popular, their method should not be relied upon to infer anything about the nature of housing supply. This note explains why.

USEFUL ELEMENTS IN BRINE FLOWING INTO THE COPPER ORE MINES OF THE FORE-SUDETIC MONOCLINE

Technologies that are currently available and still being improved are based on ion-exchange resins or membrane filters and allow carrying out effective recovery of a wide range of significantly low-concentrated elements out of the water solution. They also make it possible to lower the discharge of unwanted substances into the environment during, e.g., dewatering of mine sites. It was the reason why KGHM Cuprum Ltd Research & Development Centre undertook research in order to determine the potential of waters inflowing into the excavations of the KGHM Polska Miedź S.A. mines as a source of useful elements, including the rare earth elements. The paper presents the preliminary results of studies on contents of selected useful elements in the waters inflowing into the excavations of the Sieroszowice and Rudna mining areas (northern zone). They indicate that, due to higher concentrations, the analyzed waters might be used as a potential source of lithium, boron, rubidium, cesium and some other elements. In the study area, a zoning effect in the distribution of useful elements has been noticed. Ten zones with elevated contents of mainly lithium and boron have been distinguished there, and they were selected for further studies focused, among others, on the determination of the occurrence of rare earth elements.

Finding a Zoning Path Based on Anti-Block Ability in an Urban Traffic Network

In Urban traffic networks, a road network is usually been divided into several traffic areas by a path or a few paths, which is known as network zoning. In this paper, we present a parameter based on anti-block ability for measuring the zoning effect, which results in the ratio between the average anti-block ability of k sub-networks and the anti-block ability of whole network is minimum. We define the ratio as zoning loss factor of anti-block ability. Minimum the ratio, the model for finding a zoning vital path (ZVP for short) to divide a network into two sub-networks is established, and present an algorithm for computing the ZVP.

Étude biométrique du développement des folioles de Parkinsonia aculeata (Leguminosae)

There are three successive phases to foliolar development in Parkinsonia aculeata: (i) an initial phase during which primordium formation occurs; (ii) a morphogenic phase, with foliole formation; (iii) a histogenic and differentiation phase, with foliole development. Foliolar shape is determined during the basic morphogenic phase; a longer phase in which a zoning effect analogous to that seen in branches has been observed: (i) a zone of distal organ formation where folioles appear in constant succession, in a specific location, and in close proximity of each other along each border (these are the three criteria which define intrafoliolar generation centres); (ii) a histogenic median zone; and if the foliole is old enough (iii) a subproximal differentiation zone; (iv) an adult proximal zone.