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By Run-sheng xu, Hai-yang WANG, Di ZHAO, Teng-fei SONG, Jian-Liang Zhang

This paper was mainly focused on the different semi-cokes and charcoal which could be new fuels for blast furnace injection. Through the comparative study with bituminous coal and anthracite coal, the properties of semi-cokes and charcoal were presented in this research. 10 indexes of different fuels were obtained by different standard experiment, including proximate analysis, ultimate analysis, igniting point, explosivity, transportation characteristic, ash properties, grindability, calorific value, combustibility and reactivity with CO2. According to the data analysis, it provided a theoretical basis for rational utilization of various blast furnace fuels, and helped to broaden the scope of the blast furnace injection fuels. This research could contribute to energy conservation, emissions reduction, and sustainable development of iron and steel enterprises.

Jan 1, 2015

By Bruce T. Stanley

The concepts of ore reserve estimation at the Henderson mine are reviewed presenting a geostatistical approach and procedure as applied. Specific problems encountered are recapped and explained as to the nature and resolution thereof. The methodology and results are shown, along with an approximation of computer usage and capacities needed. The scope of the paper is to set forth an example of actual application, usage, and benefits realized from such a procedure. Local Conditions The Henderson molybdenite deposit is located in central Colorado about 69 kilometers west of Denver. The geology consists of a classic subvolcanic ryolite porphyry sequence with quartz-molybdenite mineralization occurring in an extensively fractured granite stock complex. Being assymetric and bilobate in section, the orebody measures approximately 300 meters thick and 600 meters by 1200 meters in plan. The orebody is sampled by means of underground drill holes which create an east-west fan pattern spaced roughly 60 meters apart in the north-south direction. Approximately 27,000 meters of drill hole assayed on 3.04-meter intervals were available for analysis. Recovery on the core is about 95 to 100 percent, thereby affording us with reliable data all prepared to the same standards.

Jan 1, 1977

By R. S. Dean

[During the past year the Metallurgical Fundamentals Section gave about an equal amount of time to the experimental determination of fundamental thermodynamic constants and to the demonstration of the application of such data to more directly practical metallurgical problems. The first division of the work - the actual experimental measurements of typical thermodynamic constants - was carried out an two problems, termed ?continuing? programs, namely, (1) measurements of Specific Heats at Low Temperatures and (2) Measurements of Heats of Formation and Free Energies. Specific substances chosen for investigation are classified as (n) those that have been the subject of requests for information from the industry and that, upon examination, seem of sufficient practical importance to justify study, and (b) compounds that are difficult to treat metallurgically, or whose specific thermodynamic properties have not yet been determined satisfactorily and for which accurate data might suggest improved or new methods of Metallurgical treatment, or (c) materials recognized as belonging to a social class with exceptional thermodynamic properties and, hence, of scientific as well as technical importance.]

Jan 1, 1938

By Andrew D. Lapworth

The use of geological and grade models has been standard practice in mine design for many years now, with a wide range of software available to create and analyze the models. Although geotechnical parameters are also of vital importance for mine planning, there has been very little in the way of commercially available systems for integrating geotechnical data into the mine planning and design process. Sirovision is a new technology based on digital photography for automated, safe and accurate 3D mapping of geological and geotechnical features in rock faces. Datamine has integrated this capability into its product range so that Sirovision becomes an integral part of day-to-day face mapping, mine geology and geological / geotechnical modeling in both open pit and underground mines. This results in improved fragmentation for loading, hauling and processing, and for open pits local geotechnical conditions can be taken into account to improve slope design and control. This paper describes some of the ways that geotechnical modeling can be used to create more refined and cost effective mine designs and then discusses the role of Sirovision in enabling the raw data required for such modeling to be collected quickly, safely and reliably.

May 1, 2007

By I. V. Kubrakova, O. A. Tyutyunnik, M. L. Getsina, A. M. Asavin

An analysis of noble metals (NM) in natural samples is most problematic. Determination of their traces in geochemical samples, in part, for the purpose of deposit evaluation, is a difficult analytical task. A number of international standard reference materials of rocks and ores, in which NM content is certified, is estimated at a half dozen. For example, in the International proficiency test for analytical geochemistry laboratories (GeoPT), which is held by the Department of Earth Sciences (The Open University, United Kingdom), the data for gold and platinum are observed very rarely, and the results obtained in different laboratories differ on 1-3 orders of magnitude. It is caused by low contents of NM in nature, by a variety of their complex and mineral species, as well as by a complicated matrix composition of platinum-containing objects. Among these objects are ferromanganese ores, enriched strongly with Fe, Mn, Ni, REEs - the elements hampering a precise determination of NM due to a complexity of instrumental inter-element correction. The absence of the reliable methods of NM determination in these ores drastically limits the possibility of deposit evaluation.

By F. Concha

A robust theory of sedimentation-consolidation evolved and was accepted by researchers world-wide in the last two decades of the 20th century. This theory provides a reliable method of thickener design and simulation. However, a process model, simple or sophisticated, empirical or phenomenological, is useful only if it is possible to determine, in an objective way, its experimental parameters. Research workers at the University of Concepción, together with Cettem Mineral Technology Center, created an integrated system of thickener design, simulation and control, including instrumentation, algorithm and software, which can be used by personnel in industry without specialized knowledge of thickening theory. In the paper, the development of three instruments for the measurement of pulp concentration, solid flux density and sediment compressibility is described. Each instrument uses software for data input, parameter calculation and results display. The paper also describes software for the optimization of the experimental parameter and for the design and simulation of industrial thickeners. Finally, mathematical algorithm and control strategies based on the phenomenological model are presented and compared with classical feedback control.

Jan 1, 2014

By S. Fahland, P. Vogel

"The Gorleben salt dome has been investigated since 1979 for its suitability as a repository for the disposal of high-level radioactive wastes. The geoscientific surface exploration was followed by underground exploration of the site beginning in 1983: underground excavation work included the sinking of two shafts from 1986 to 1994, the excavation of the infrastructure area and of drifts located in the first exploration area EB1 within the following years. The exploration was interrupted for ten years from 2000 to 2010 as part of a moratorium. After the expiry of the moratorium in March 2010, the geoscientific underground exploration at the Gorleben site was resumed. The investigations were interrupted again in autumn 2012 due to a political decision. The exploration programme included extensive geoscientific investigations: geological exploration, geophysical investigations, mining exploration and mining observation, laboratory tests, in-situ geotechnical measurements, geological modelling and numerical model calculations. To analyse and interpret the results of the in-situ measurements and mining observation geomechanical, thermal and thermo-mechanical model calculations were carried out. One of the main elements of the in-situ geotechnical investigations were high-resolution geothermal measurements performed in boreholes used for geological exploration and geotechnical tests.The geothermal measurements are used to evaluate several geotechnical findings, e. g. drift closure, rock deformation, stress change, and are completed by thermal model calculations to analyse and interpret the results of in-situ measurements and mining observation. The model calculations have been carried out using the special purpose JIFE code. To consider the whole exploration mine with the adjoining host rock as well as the successive excavation of drifts and boreholes in detail a three-dimensional finite-element model was developed. The model calculations are used to analyse the cooling-off of the surrounding rock of the drifts caused by ventilation. The cooling-off of the surrounding rock is an ongoing process affecting the results of further geotechnical measurements in the near field of the drifts. To predict a realistic time and space dependent distribution of the temperature field of the host rock within the exploration area which is influenced by ventilation thermal model calculations are necessary. Comparing the calculated temperature field with the in-situ determined rock mass temperature field within the exploration area EB 1 the results show a sufficient agreement. Furthermore there is very good correspondence, both qualitatively and quantitatively, between the experimental and the calculated findings regarding the temperature profiles including the effects of excavation and ventilation of the drifts."

Jan 1, 2015

By C. V. Corless

THE origin of various types and groups of ore deposits was some years ago a subject of much controversy. To this statement the copper-nickel deposits near Sudbury afforded no exception. Not since the Report of the Ontario Nickel Commission, in 1917, has there been any serious discussion of the origin of this very important group. This may be because, from the opening-up of Murray mine by the British America Nickel Corporation until the recent work at Frood mine, no new ore-body of importance has been developed in the district. The controversy fifteen or twenty years ago between those who favoured the theory of magmatic segregation, among whom Dr. A. P. Coleman was the leading exponent, and those who considered that most, if not all of the Sudbury deposits could more satisfactorily be accounted for by the theory of replacement, will be remembered by many members of the Institute. Perhaps, as too often happens in controversial discussion, each side tended to overemphasize the importance of those geological phenomena which seemed to be most easily accounted for by the theory it favoured. A more balanced view would perhaps admit that replacement was probably predominant in the formation of most of the offset deposits, and magmatic segregation in that of most of the marginal deposits . But there is danger in generalization. Each body of ore should be studied by itself, and no general conclusion of this kind should be allowed to warp the judgment in making such a study.

Jan 1, 1929

By L. Narhi, K. Haavanlammi

"Approximately two thirds of annual nickel production is used as a raw material in the making of stainless steel, and about 60% of these nickel products are in the form of metallic nickel such as nickel cathode or briquettes. In the stainless-steel production process nickel is blended with iron and chrome-based raw materials, and metallic nickel is typically only required for final steel fine-tuning. Outotec offers a new FeCrNi technology to enhance the nickel value chain for stainless steel producers. This involves the use of an HPAL-based intermediate nickel product (e.g., mixed hydroxides or NiO) as raw material in the Outotec FeCrNi process, for the production of a FeCrNi Master Alloy. The new process, designated as the FeCrNi process, offers multiple benefits compared to existing technologies such as: higher tolerance for impurities in the HPAL intermediate product, avoiding the need for further nickel refining, and the improved recovery of all metals in the FeCr process. The complete new FeCrNi value chain is based on proven technologies such as HPAL and the Outotec FeCr-process. This new innovative and promising value chain offers improved efficiencies for the HPAL based nickel production process combined with excellent sustainability aspects.INTRODUCTION In today’s global economy there is a constant need to improve the efficiency and sustainability of the metals production. The requirements for modern metal refining are tightening and cost efficient, safe and sustainable operation is the precondition for all investment. Outotec is offering now a novel way to combine FeCr and Nickel production to create a completely new value chain to source nickel to stainless steel. BACKGROUND Nickel The current nickel mine production is in the level of 2,000 tons annually and it is split 44% from sulphide based deposits and 56% from laterite deposits (Figure 1). Most (40%) of the nickel is refined to pure nickel metal whereas other products are FeNi (19%) and Nickel Pig Iron NPI (20%) (Roskill). The remaining part, roughly 21%, is nickel chemicals and intermediates. Most of the new investments in nickel are in the direct shipping of laterite to produce nickel pig iron. HPAL process is considered in few projects but no major HPAL projects have been started since the Ambatovy plant in Madagascar. Ambatovy reached the commercial production in 2014. The main primary nickel used is stainless steel manufacturing. In the year 2016 about 68% (~1,360 kt) of primary nickel production was used in stainless steel."

Jan 1, 2017

Improve the safety and comfort of operators of large mining equipment. Approach Develop an improved driver restraint system that is easy to use, reliable, and cost-effective, while providing increased protection in the event of a collision or rollover. The Novel Restraint System There are several problems associated with conventional lap-belt type restraint systems. Among these are: restriction of movement, lack of comfort, and fear of entrapment. Standard seatbelts become dirty and oily from lying on the vehicle cab floor and can ruin a driver's clothes. Some haulage equipment may not even have seatbelts available to drivers since they are sometimes removed during maintenance activities or as a result of vandalism. Recognizing a need to address such problems by providing a more acceptable means of driver restraint, the Bureau of Mines designed and fabricated a novel vest-type restraint system. The vest is designed to be worn during a driver's 8-hour shift and would be issued much like safety glasses, hard hats and safety shoes, thus becoming part of the operator's individual protective equipment and assuring that each vehicle has a restraint system when in operation. The vest-

Jan 1, 1985

By R. F. Bell, Schultz

The paper briefly discusses the nature of spontaneous heating in mines in the Doncaster area, in the period immediately before 1967 and steps taken to prevent and treat such outbreaks. The changes that led to the increased rates of advice of Barnsley Seam faces since 1967 are listed and the effects of these increased rates on the frequency and location of spontaneous combustion are discussed. The change in methods of control required by the increased rate of advance of the faces and the changes in location of outbreaks are described. Some typical heating situations are evaluated. The methods described include the use of air sealants, water gels for filling of voids in wastes, the balancing of pressures across heating areas by pressure chambers, booster fans, and the resiting of air separation doors, and the sealing of air-ways by flooding. The authors discuss the influence of mine layouts on the risks of spontaneous combustion and advocate that future plans should be designed to limit the number of districts at risk when heatings occur.

May 23, 1905

By R. E. Cerullo

Many computer programs have been written which are capable of performing a least squares fit, both linear and nonlinear, to data gathered by the petroleum researcher. However, when the petroleum engineer tries to program methods of analysis he has used manually in the past, such as forecasting production by decline-curve analysis, more than a knowledge of the use of existing least squares programs becomes necessary. It is the intent of the authors to report the techniques used in the development of such a decline-curve program.

Jan 1, 1970

By T. G. Joseph, M. Bolster, M. Curley

"High tirerim loading on haul trucks operating on rough ground frequently manifests as mechanical separations and rim base cracking caused by cyclic fatigue. This paper provides an understanding of the impact of high loads on rim component life and tire footprint, bulge, and deformation behaviour; and develops a maintenance planning tool to predict strain implications of high g loading for a given rim location. Loading tests and analyses were conducted for a tirerim arrangement under increasing load and internal tire pressure. Graphical models were developed, allowing higher g load extrapolation predictions for specific rim components.KEYWORDS g load, Mining, Model, Prediction, Rim, Strain, Tire bulge, Tire footprint, Ultra-class vehicleRÉSUMÉ L’application d’un chargement élevé sur le système pneu/jante de camions de transport rou¬lant sur des terrains accidentés se manifeste fréquemment par des séparations mécaniques et une fissure à la base de la jante engendrée par une fatigue cyclique. Cet article nous permet de mieux comprendre l’incidence de l’application de charges élevées sur la durée de vie des composantes de la jante ainsi que sur l’empreinte, la hernie et le comportement de déformation des pneus. Il développe également un outil de planification de l’entretien visant à prévoir l’incidence des contraintes en cas d’application d’un chargement g élevé sur un endroit donné de la jante. Des essais et des analyses de la charge ont été effectués pour un agencement pneu/jante soumis à une charge et une pression interne du pneu croissantes. Des modèles graphiques ont été développés, ce qui a permis d’établir des prédictions sur la base d’une extrapolation du chargement g plus élevé appliqué à des composantes spécifiques de la jante.MOTS CLÉS charge g, contrainte, empreinte du pneu, exploitation minière, hernie du pneu, jante, modèle, prédiction, véhicule ultralourdINTRODUCTION The purpose of this paper is to report on a proposed and trialed tire performance test based on data obtained from controlled testing that is used to predict the impact of high g loading on hauler rims and tires with greater accuracy. For example, for many years oil sand mining operations have expressed qualitative beliefs that an impact load of the magnitude experienced by a rim and tire arrangement is not detrimental to a rim as a stiff component; however, mining equipment components are subjected to cyclic loading where failure can result from repeated load/unload activity, truncating the peak region of a stress–strain response and resulting in fatigue failure at a stress value that is less than the peak value. The outcome reported by oil sand haul truck maintenance groups indicates they have realized that most high g impacts—such as those experienced by hauler tires and rims operating on poor ground conditions—can result in failure due to cyclic loading, where higher loads require fewer cycles for failure. This high-level loading and the resulting strain transmitted to the rim is evident in the results of the laboratory testing presented in this paper."

Jan 1, 2019

By Tom Learmont

The importance of coal in solving our energy problems has been widely discussed; the world demand for food requires increased fertilizer production and the minerals to produce fertilizer must be mined. We have seen an explosive increase in the demand for large stripping equipment. It is appropriate that we review this equipment and determine what can be done to improve productivity. While we have used coal mining as an example in the study, much of the discussion will apply equally to other forms of stripping.

Jan 1, 1975

By Juan B. Yianatos

"After almost 100 years, since the first commercial application began in Australia, flotation has shown an extraordinary growth and nearly 2 billion tons of ore per year are presently treated by flotation processes. During this time flotation has promoted a wide scope of research activities ranging from fundamental chemistry and hydrodynamic studies to studies of industrial operations. In general, fundamental studies have been mainly related to ideal situations. In recent years, however, large efforts have been focusing on achieving a better insight into the actual sub-processes provided by the development of new and more sophisticated instrumentation. Since the massive incorporation of flotation columns, around 15 years ago, a renewed interest in flotation fundamental studies, process modelling and new cell designs have been observed worldwide. The key role of the froth has been recognized as an independent and sometimes rate limiting process step. Thus, separation of pulp and froth process stages seems the most appropriate in terms of process modelling, diagnostic, design and scale-up purposes.In relation to flotation equipment development, until the middle of the 1970’s, only the sub-aeration mechanical cells were dominant. Since the 1980’s, the use of pneumatic cells and forced air mechanical cells has emerged strongly. Also, in the last decade, flotation equipment has shown a dramatic increase in size, reaching values of 200m3 in unitary mechanical cells and more than 300m3 in columns. The general feeling, however, is that, despite the great advance observed in terms of process knowledge, the mechanisms and principles of industrial flotation cells design and scale-up are still not fully understood.Advances in process instrumentation and control now in use allow for more efficient operations, both in metallurgical performance and savings in operating costs."

Jan 1, 2003

By Juan B. Yianatos

"After almost 100 years, since the first commercial application began in Australia, flotation has shown an extraordinary growth and nearly 2 billion tons of ore per year are presently treated by flotation processes. During this time flotation has promoted a wide scope of research activities ranging from fundamental chemistry and hydrodynamic studies to studies of industrial operations. In general, fundamental studies have been mainly related to ideal situations. In recent years, however, large efforts have been focusing on achieving a better insight into the actual sub-processes provided by the development of new and more sophisticated instrumentation. Since the massive incorporation of flotation columns, around 15 years ago, a renewed interest in flotation fundamental studies, process modelling and new cell designs have been observed worldwide. The key role of the froth has been recognized as an independent and sometimes rate limiting process step. Thus, separation of pulp and froth process stages seems the most appropriate in terms of process modelling, diagnostic, design and scale-up purposes.In relation to flotation equipment development, until the middle of the 1970?s, only the sub-aeration mechanical cells were dominant. Since the 1980?s, the use of pneumatic cells and forced air mechanical cells has emerged strongly. Also, in the last decade, flotation equipment has shown a dramatic increase in size, reaching values of 200m3 in unitary mechanical cells and more than 300m3 in columns. The general feeling, however, is that, despite the great advance observed in terms of process knowledge, the mechanisms and principles of industrial flotation cells design and scale-up are still not fully understood.Advances in process instrumentation and control now in use allow for more efficient operations, both in metallurgical performance and savings in operating costs.INTRODUCTIONFlotation is a widely used process within the minerals processing industry, as well as being used for water treatment and de-inking of recycled paper. Froth flotation started in Australia at the beginning of the 20th century and since then flotation technology has made significant advances. Flotation was firstly applied to sulfide ores. The largest tonnages treated by flotation are copper and copper/molybdenum ores, handling about 50% of the total ore processed. Also significant are phosphate, iron ore and coal treatments. At present, Chile is the foremost copper producer in the world with around 35% of the world?s production. Figure 1(a) shows the evolution of copper production in Chile over the last decade. The total amount of fine copper produced in year 2001 was 4.7 million tons, from which 3.2 million tons was processed by flotation while 1.5 million tons went through LIX-SX-EW processes, which also showed significant development during the same period (Anon, 2001). The total flotation treatment of copper ores in Chile is about 325 million tons per year (Anon, 2002), so the world treatment of copper ore by flotation can be estimated at about 1 billion tons per year. Consequently a total of nearly 2 billion tons of ore per year is presently processed worldwide by flotation (Fuerstenau, 2001). In order to handle the higher tonnage of low-grade ore, a worldwide trend towards the development and use of larger flotation machines began in the 1960?s. Figure 1(b) shows that the trend became extremely marked from the beginning of the 1990?s, which is consistent with the strong increase in copper production during the same period."

Jan 1, 2003

By Rick Piovesan, Pramod Rao, Nihal Bohra, Mark Wahler

"This paper discusses the approach followed for the geotechnical design of 355 mm and 457 mm diameter driven open-ended steel pipe piles used for a gas plant at a green field site in Pilbara region in Australia. The principal bearing layer at the site comprises of calcareous Red Bed soils and weak rock, which is the typical geology along a significant length of the northern Western Australian coastline with carbonate content up to 70%. The uncertainty associated with the mechanical behavior of the calcareous soils and cemented soils (weak rocks) presented design challenges in the selection of appropriate pile design method and design parameters for pile capacity estimation during Front End Engineering Design (FEED). The American Petroleum Institute (API)-based design methodology was adopted. The representative design parameters for the Red Bed weak rock were established by treating the weak rock as clay with undrained shear strength as one-half of the characteristic unconfined compressive strength (UCS) value. Both statically load tested and CAPWAP (Case Pile Analysis Wave Program) estimated ultimate axial pile capacities on 25 early pre-production indicator piles demonstrated that the API design methodology for siliceous soils provides reasonable prediction of axial pile capacity in the red bed soils/weak rock and no reduction to API computed axial capacity due to carbonate content is warranted. The results also demonstrated that penalizing axial pile capacity solely based on carbonate content is not appropriate.IntroductionA gas processing facility was proposed to commercialize the gas reserves located 130 km offshore from the north-west coast of Western Australia (WA). The project site is a green field site located in the Pilbara region along the northwest coast of WA. Specific information regarding the site has been withheld due to confidentiality reasons. The site layout is shown in Figure 1.The site comprises low-lying tidal flats, clay pans and sand dunes covered with low scrub. The onshore site levels vary from elevation 1 m to 10 m AHD (Australian Height Datum), with the largest proportion of the area (excluding sand dunes) between elevations of 1 m and 3 m.The onshore facilities are to comprise a liquefied natural gas (LNG) plant site, a construction camp, the land-based portion of the materials offloading facility (MOF), roadways, and borrow pit areas.The existing ground levels within the process train area, where pile load testing was performed, vary from over 7 m AHD where the summits and peaks of the central dune exist to typically 1 m to 2 m AHD towards the east and west edges of the dune. The proposed finished grade for the process train is set at 7 m AHD."

Jan 1, 2015

By Marco Quirion

The Daniel-Johnson dam, formerly named Manicouagan-5 (Manic-5), is located 800 km northeast of Montreal (Quebec) in Canada. This is the largest multiple-arch concrete dam in the world consisting in 13 arches and 14 buttresses. Since its construction in 1969, various type of cracks have appeared on both downstream and upstream faces of almost all the arches of this concrete dam. As a part of the Daniel- Johnson’s dam safety assessment program, Hydro-Québec is currently performing structural analysis of the dam with advanced numerical models to better understand and predict the dam behaviour. Because the buttresses transmit all the arch loads to the rock mass, determination of the properties of the dam foundation should not be neglected in dam global safety analysis and also to insure that reliable input parameters are used in the dam numerical simulations. This paper summarizes the past and the more recent investigations of this foundation used to assess its safety and stability. Moreover, the use of rock mass classification to estimate the deformation modulus, based on empirical equations, gives values in the range of 30 to 40 GPa that are higher than expected values. Using those values in the numerical simulations for dam structural analysis gives an excellent correlation with displacements monitoring of the buttresses.

Jan 1, 2015

By Hugh J. Leach, J. C. Van de Water

In open pit mining, as in other industries, it has I become necessary to improve operating efficiency in order to combat higher labor and supply costs. Moreover, orebodies are becoming leaner, pits are getting deeper, stripping ratios are increasing, and hauls are getting longer. There has been a steady increase in size, speed of operation, and reliability of the various machines involved in breaking, loading, and hauling ore. Changes have seldom been radical but are rather the result of steady improvement. Drilling: Notable advances have been made in the use of rotary drills and air powered percussion drills for blasthole drilling. Several hundred of these machines are now in use as replacements for churn drills in softer rocks such as limestone and shale. Their application to hard rocks such as iron ore and taconite is under current investigation, but in the Lake Superior iron mining district, open pit blast-hole drilling in ore has been accomplished almost exclusively by standard churn drilling. The only recent advance has been the use of larger machines drilling 9-in. holes. This has increased drilling speed somewhat and allowed wider hole spacing, with consequent cost reduction.

Feb 1, 1956

By John W. Harbaugh, Alfredo Prelate

The goal of the study described here is to develop objective. quantitative methods for estimating the outcome probabilities of exploratory oil wells. The study employs the 're-experience' approach, in which historical data are used in a manner which attempts to recreate the past. Our past experience, of course, is the principal guide to the future. To appraise present-day oil prospects, however, we must analyze prospects that have been drilled in terms of how these former prospects were interpreted before they were drilled. An analysis of how they are interpreted after they were drilled is an inadequate guide to the future because our hindsight knowledge is superior to our foresight knowledge. Objective calculation of future outcome probabilities, then, requires that we attempt to treat past information in a manner analogous to that in which we must treat present information in forecasting future outcomes.

Jan 1, 2014