The Groucho Effect of Uncertain Standards

Consumers are rarely sure of the exact standard that product labels and other certificates of quality represent. We show that any such uncertainty creates a “Groucho effect” in which seeing that a product has a label leads consumers to infer that the standard for the label itself is not very demanding. Label adoption is therefore always less likely to be an equilibrium than without uncertainty over the standard, and if it is an equilibrium it is always less informative than without such uncertainty. The Groucho effect leads to an information externality so better firms are reluctant to adopt labels if worse firms adopt them. Applying the model to eco-labels, we find that industry groups, governments, and NGOs can increase label adoption by publicizing labeling criteria, by encouraging consumers to expect label adoption when there are multiple equilibria, and by setting high standards that are less likely to be devalued by low quality firms.Eco-labels, disclosure, certification, persuasion, standards

A Computer Method for Four-Variable Trend Analysis Illustrated by a Study of Oil-Gravity Variations in Southeastern Kansas

A method for fitting four-variable trend hypersurfaces by least squares has been programmed for the IBM 7090 computer. The program fits first-, second-, and abbreviated third-degree hypersurfaces to irregularly spaced data. The program automatically contours the intersection of each hypersurface with a block whose top, bottom, and four sides represent planes located in three-dimensional space. This permits the four-variable or four-dimensional hypersurfaces to be visualized. The program also automatically plots original data and residual values in a series of horizontal slice maps. The theory and operation of the program are discussed and illustrated in detail. The program has been used to interpret variations in crude oil gravity from place to place and in different Paleozoic stratigraphic horizons in southeastern Kansas. Hypersurfaces were fitted to API oil gravity as a function of geographic location and depth below the surface. The four variables involved are (1) API gravity, (2) well depth, (3) north-south geographic coordinates, and (4) east-west geographic coordinates. The trend hypersurfaces, distribution of residual values, and other considerations suggest that oil-gravity variations in southeastern Kansas have been affected by both well depth and environment of deposition. The tendency for API gravity to increase with depth is complicated by regional effects that may reflect differences in environment of deposition. The result is an overall increase in API gravities in a west-northwest direction. Of interest is a tendency for residual API gravity "highs" and "lows" to be clustered in certain geographic areas even though oils from different stratigraphic zones are involved. This, in turn, suggests that the depositional environment may have affected oil gravities in a given locality much the same way from one geologic period to the next. The computer program described in this report may have a number of geological applications, and can be used readily by anyone having access to an IBM 7090 or 7094 computer

Petrology of Marine Bank Limestones of Lansing Group (Pennsylvanian), Southeast Kansas

Limestones of the Lansing Group in the Wilson-Montgomery County, Kansas, area contain small patches of coarsely crystalline calcite that exhibit two types of fabric, one formed by precipitation of calcium carbonate in cavities; the other by recrystallization of carbonate silt or fine skeletal debris by a process termed grain growth. Filled cavities are associated with leaf-like fragments of algal crusts; which, during deposition, served as umbrellas, catching carbonate silt and skeletal debris on their upper surfaces and maintaining sheltered open spaces beneath. Cavities also were formed between fragments of partly consolidated carbonate silt that formed sedimentary breccias. Algal crusts and fragments of other organisms tended to accumulate in thickened lenses or banks, which rose above the level of the surrounding sea floor and extended over many square miles. The banks were seemingly too poorly consolidated initially to have formed wave-resistant reefs. Solution pores in Lansing limestone specimens obtained at outcrops show that small-scale lithologic features have exerted a large effect in localizing pores. Many pores occur within coarsely crystalline mosaics, particularly those formed as open-space precipitates. Other pores are localized at the boundaries of mosaics, at the contacts between individual skeletal particles, within algal crusts, and within dolomitized patches. Fractures, both large and small, also have had large influence in localizing pores. Development of porosity in buried Lansing limestones that serve as oil-reservoir rocks may be influenced similarly

Marine Bank Development in Plattsburg Limestone (Pennsylvanian), Neodesha-Fredonia Area, Kansas

The Plattsburg Limestone is anomalously thick in the Neodesha-Fredonia area, increasing from an average of about 20 feet to a maximum thickness of 115 feet. Thickening is due to increase in the Hickory Creek Shale (middle member) from 1 to 45 feet, and the Spring Hill Limestone (upper member) from 3 to 88 feet in thickness. The Plattsburg Limestone and the overlying Vilas Shale have been studied in outcrops in the eastern part of the Neodesha-Fredonia area and have been traced underground in the central and western parts of the area by means of about 200 drillers logs. Nineteen outcrop sections, measured, described, and sampled in detail, form the basis for lithologic and genetic interpretations. About 150 rock samples were studied microscopically by means of acetate peels and enlarged negative photographic prints made from the peels. The principal cause of thickening of the Plattsburg Limestone is interpreted to be deposition of an extensive, lens-shaped marine bank that rose above the general level of the surrounding sea floor. The bank was at least 14 miles long in a northwest-southeast direction, and about 10 miles wide. Two smaller, detached thickened portions of the Plattsburg Limestone in the area probably represent small banks. A second cause of thickness variations in the Plattsburg Limestone is local structural warping during deposition, which permitted greater thicknesses to accumulate over downwarps and lesser thicknesses over upwarps. Thickness of the Vilas Shale also has been affected by this cause. Thickness of the Vilas Shale has been observed to be inversely related to thickness of the Plattsburg Limestone at most localities. Part of the Vilas Shale is interpreted to be an off-bank time equivalent of part of the thickened Spring Hill member. Deposition of the bank is interpreted to have been strongly influenced by lime-secreting organisms, including crinoids, bryozoans, brachiopods, mollusks, and algae. The organisms may have influenced deposition of silt and clay (Hickory Creek member) by exerting a sediment-binding effect, and probably helped stabilize slopes at least as great as 7° on the edges of the bank. In addition, they contributed large quantities of calcareous material to the upper part (Spring Hill member) of the bank. Where thick, the Spring Hill member of the Plattsburg is divided into three tabular lithologic subdivisions in regular vertical sequence. The lower subdivision contains abundant irregular fragments and pellets, much of it seemingly of algal origin. The middle subdivision contains abundant visibly crystalline calcite intimately associated with encrusting calcareous algae. The upper subdivision contains abundant calcarenite composed of grains of various degrees of rounding and sorting. During deposition of the crystalline subdivision, lime-secreting algae may have imparted rigidity to deposits forming on the bank, thus creating a reef if the bank extended into shallow water. During deposition of other parts of the Plattsburg bank, the deposits probably were not wave resistant. Porosity in the Spring Hill member is related to limestone lithology. The crystalline limestone subdivision, where pores and vugs are conspicuous in visibly crystalline calcite, is most porous. The thickened Spring Hill Limestone of the Neodesha-Fredonia area may provide an example of a porous limestone lens that might serve as an oil reservoir; some oil pools in Pennsylvanian limestones of central and western Kansas may occur in porous lenses of similar origin

Relative Ages of Visibly Crystalline Calcite in Late Paleozoic Limestones

Four types of visibly crystalline calcite occur in late Paleozoic limestones examined in this study. (A) Grain-growth calcite, characterized principally by irregular size and shape and random orientation of crystal grains, probably formed by solid-state recrystallization of microcrystalline calcite sediment. (B) Blade calcite, characterized by tapered, blade-shaped crystals bunched in flower-like aggregates, probably formed by recrystallization under mild shearing stresses. (C) Encrusting calcite, characterized by aggregates of fibrous to irregular crystals, probably formed by precipitation around algal tissues that subsequently decayed. (D) Void-filling calcite, characterized by orientation of crystals perpendicular to walls of filled voids and by general increase in crystal size toward center of filled voids, formed through inorganic precipitation. Encrusting calcite probably formed during deposition of surrounding sediment and seems to be the earliest of the calcite types to form. Most void-filling calcite probably formed early in the limestone\u27s history, during or soon after partial consolidation of fine sediment. Early filling of voids, reducing the porosity, probably inhibited compaction. Although its age relations are poorly known, grain-growth calcite is probably not older than most of the adjacent void-filling calcite. Blade calcite and void-filling calcite that occupies post-lithification fractures and other openings seem to be the latest to form. Visibly crystalline calcite may be defined simply as calcite consisting of crystals that are large enough to be seen readily as individuals in thin section at low magnification. In this respect, visibly crystalline calcite contrasts with microcrystalline calcite, which consists of crystals either too small or too poorly defined to permit individual crystals to be distinguished. The distinction between visibly crystalline calcite and microcrystalline calcite is a semi-quantitative one. Limits between the two types, in terms of dimensions of individual crystals, cannot be precise, however, because size of crystals intergrades continuously. This paper is based principally on the study of Pennsylvanian limestones, particularly those of the Upper Pennsylvanian Lansing Group in southeast Kansas and parts of the Magdalena Limestone (Pennsylvanian) in the Caballo Mountains of southwest-central New Mexico and the Hueco Mountains of West Texas. In addition, several hundred specimens from various Pennsylvanian and Permian limestone units in Kansas and the McCloud Limestone (Permian) of northern California have been examined for comparison. Conclusions drawn in this study are probable applicable to many late Paleozoic limestones, and perhaps to limestones of other ages as well. Both thin sections and acetate peels have been examined in studying the limestones described here. Peels are superior in some respects because of the great fidelity with which they reproduce the microscopic details of the limestone. Methods of preparing and photographing peels have been described previously (Harbaugh, 1959, p. 295)

Critical Currents of Josephson-Coupled Wire Arrays

We calculate the current-voltage characteristics and critical current I_c^{array} of an array of Josephson-coupled superconducting wires. The array has two layers, each consisting of a set of parallel wires, arranged at right angles, such that an overdamped resistively-shunted junction forms wherever two wires cross. A uniform magnetic field equal to f flux quanta per plaquette is applied perpendicular to the layers. If f = p/q, where p and q are mutually prime integers, I_c^{array}(f) is found to have sharp peaks when q is a small integer. To an excellent approximation, it is found in a square array of n^2 plaquettes, that I_c^{array}(f) \propto (n/q)^{1/2} for sufficiently large n. This result is interpreted in terms of the commensurability between the array and the assumed q \times q unit cell of the ground state vortex lattice.Comment: 4 pages, 4 figure

Reassessment of the Rates at which Oil from Natural Sources Enters the Marine Environment

Previous estimates of the world-wide input of oil to the marine environment by natural seeps ranged from 0 ·2 to 6 ·0 million (metric) tonnes per year with a \u27best estimate\u27 of 0 ·6 million tonnes per year. Based on considerations of the availability of oil for seepage from the world\u27s known and assumed oil resources, we believe that the world-wide natural oil seepage over geological time should be revised to about 0 ·2 million tonnes per ),ear with a range upward or downward of a factor of ten leading to estimates between 0 ·02 and 2 million tonnes per year. Our estimate of the amount of oil eroding from the land and being transported to the oceans is about 0 ·05 million tonnes per year with an order of magnitude uncertainty. Therefore, while the uncertainties are large, we estimate that the total amount of oil entering the marine environment by natural, geological processes, is about 0 ·25 million tonnes per year, and the estimate may range from about 0 ·025 to 2 ·5 million tonnes per year

Upper Pennsylvanian Calcareous Rocks Cored in Two Wells in Rawlins and Stafford Counties, Kansas

This report describes Upper Pennsylvanian rocks encountered in continuous cores taken from the Skelly Oil Company No. 1 Bartosovsky well in sec. 9, T 1 S, R 34 W, Cahoj oil field, Rawlins County, and the Stanolind Oil and Gas Company (now Pan American Petroleum Corporation) No. 3 Denker well in sec. 10, T 22 S, R 12 W, Max oil field, Stafford County, Kansas. Lithology and small-scale petrologic features of the limestones and calcareous siltstones in the cores are described in detail and illustrated in photographs. Porosity and permeability data obtained from core analyses are shown graphically. Most porosity is related to sedimentary breccias, stylolites, masses of void-filling calcite, fractures, oolites, and fossils. Breccias and calcite masses are interpreted to have formed partly as a result of contraction of the sediment before final consolidation

Reconstructing Late Cenozoic Stream Gradients from High-Level Chert Gravels in Central Eastern Kansas

Interpreting the evolution of Kansas' landscape east of the Flint Hills provides major challenges. In the Neogene (late Tertiary) and perhaps part of the Pleistocene, streams transported a variety of sedimentary materials, including chert gravels derived from the Flint Hills. Gentle intermittent uplift stimulated the stream system to cut down, locally removing and reworking the gravels to create stream-terrace deposits that consist mostly of chert pebbles, which now lie well above the floodplains of modern streams. By correlating the elevations of these gravels, the gradients of the trunk streams that deposited them can be reconstructed. Interestingly, these ancient streams flowed southeast at a little more than a foot per mile (0.2 m/km), roughly the same as the gradient of the trunk streams in the region today. The evolving landscape in eastern Kansas also has been strongly influenced by an extensive network of fractures that is widespread in the midcontinent region and may be worldwide in extent. In northeastern Kansas, glaciation during the Pleistocene disrupted the southeasterly drainage and established the present location of the Kansas River. South of the Kansas River and its immediate tributaries, however, the general southeasterly drainage has been preserved. We have made use of the wealth of topographic-elevation data now available in digital form known as DEMs or digital elevation models. Coupled with GIS procedures, the DEMs helped link the mapped distribution of chert gravels with hypothetical fitted surfaces that represent ancient stream gradients. Furthermore, DEM data placed in shaded-relief map form emphasize the influence of fractures in evolution of the drainage system

Peracute Infection of Swine With Salmonella

It has recently been experimentally demonstrated that pigs exposed naturally to Salmonella on the floor of abattoir holding pens can become infected between two and six hours after being placed in the pens. In addition we have demonstrated that tonsillar tissue are almost immediately culture positive following such exposure under experimental conditions. The objective of this study was to determine the shortest amount of time necessary for infection of selected tissues and to determine if the tonsil served as a route for Salmonella entry into lymphoid tissues draining the tonsil. Forty-four Salmonella-negative, market age pigs (90 to 110 kg) were fasted overnight and exposed to approximately 2 X 106 Salmonella enterica serotype Typhimurium strain X4232 (nalidixic acid resistant). The bacteria were mixed with a fecal slurry and the slurry spread on the floor of the pens. Pigs were euthanized at 15, 30, 45, 60 and 120 minutes following initial exposure. Tonsil of the soft palate, medial retropharyngeal lymph node, ileocecal lymph node, a five centimeter section of the terminal ileum, cecal contents and 100 ml of blood were cultured for Salmonella. Strain X4232 was isolated from 98 % (43/44) of tonsils. Strain X4232 was isolated from the ileocecal lymph node within 45 minutes (2/9 pigs), terminal ileum within 15 minutes (1/9 pigs), cecal contents within 15 minutes (1/9 pigs), and blood within 45 minutes (1/9 pigs). Strain X4232 was not recovered from the medial retropharyngeal lymph node, indicating that the organism did not move rapidly into this node from the tonsil of the soft palate. Results of this study indicate that Salmonella can be recovered from selected tissues in market age swine in less than the normal two hour abattoir holding time