AI-GEOSTATS: Invitation to connect on LinkedIn
LinkedIn AI, I'd like to add you to my professional network on LinkedIn. - M. Nur M. Nur Heriawan Lecturer at Mining Engineering Department, Bandung Institute of Technology Indonesia Confirm that you know M. Nur Heriawan https://www.linkedin.com/e/dgf4jv-ghonvkrj-4s/isd/2022205333/5gtJDAY8/ -- (c) 2010, LinkedIn Corporation
AI-GEOSTATS: geostat for alluvial deposit
Dear list, I need references about the application of geostatistics for the resources estimation of alluvial and placer deposits. If someone in the list has experiences about it, could you please share it? As you might know that alluvial deposits i.e. gold or tin has very high variability in the lateral direction, so the resources classification based on the variogram range is seemed to be not appropriate. Anyway, when we used the kriging standard deviation for resources classification, the result was seemed to be not reliable. Thank you for any suggestions. Best regards,--- M. Nur Heriawan Earth Resources Exploration Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40132 INDONESIA http://www.mining.itb.ac.id/heriawan + + To post a message to the list, send it to ai-geost...@jrc.ec.europa.eu + To unsubscribe, send email to majordomo@ jrc.ec.europa.eu with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
Re: AI-GEOSTATS: moving averages and trend
Goovaerts, regarding the factorial kriging you mentioned below...is it possible to filter the micro component (nugget effect) from our spatial model? Because the magnitude of nugget effect is related to the magnitude of variance error as well. Thank you. Regards,--- M. Nur Heriawan Earth Resources Exploration Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40132 INDONESIA http://www.mining.itb.ac.id/heriawan From: Pierre Goovaerts goovae...@terraseer.com To: seba sebastiano.trevis...@libero.it Cc: José M. Blanco Moreno jmbla...@ub.edu; ai-geostats@jrc.it Sent: Tue, February 2, 2010 12:27:09 AM Subject: Re: AI-GEOSTATS: moving averages and trend well Factorial Kriging Analysis allows you to tailor the filtering weights to the spatial patterns in your data. You can use the same filter size but different kriging weights depending on whether you want to estimate the local or regional scales of variability. Pierre 2010/2/1 seba sebastiano.trevis...@libero.it Hi José Thank you for the interesting references. I'm going to give a look! Bye Sebastiano At 15.46 01/02/2010, José M. Blanco Moreno wrote: Hello again, I am not a mathematician, so I never worried too much on the theoretical reasons. You may be able to find some discussion on this subject in Eubank, R.L. 1999. Nonparametric Regression and Spline Smoothing, 2a ed. M. Dekker, New York. You may be also interested on searching information in and related to (perhaps citing) this work: Altman, N. 1990. Kernel smoothing of data with correlated errors. Journal of the American Statistical Association, 85: 749-759. En/na seba ha escrit: Hi José Thank you for your reply. Effectively I'm trying to figure out the theoretical reasons for their use. Bye Sebas -- Pierre Goovaerts Chief Scientist at BioMedware Inc. 3526 W Liberty, Suite 100 Ann Arbor, MI 48103 Voice: (734) 913-1098 (ext. 202) Fax: (734) 913-2201 Courtesy Associate Professor, University of Florida Associate Editor, Mathematical Geosciences Geostatistician, Computer Sciences Corporation President, PGeostat LLC 710 Ridgemont Lane Ann Arbor, MI 48103 Voice: (734) 668-9900 Fax: (734) 668-7788 http://goovaerts.pierre.googlepages.com/
AI-GEOSTATS: kriging variance and resources classification
Dear list, I am searching any references which can address the relationship between kriging variance and mineral resources classification (measured, indicated, and inferred). Is there rule of thumb for that? As I know, kriging variance only takes into account drilling spacing and variogram model, while grade value is not related to it. I hope anybody in the list could give me the hint. Thank you. --- M. Nur Heriawan Earth Resources Exploration Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40132 INDONESIA http://www.mining.itb.ac.id/heriawan + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: DDH vs BH
Dear list, I am doing the structural analysis for Pb-Zn grade in 3D. In the first step, I have used the diamond drill hole (DDH exploration) data. Then I work separately using blast hole (BH) data with number of data is much larger than DDH, but BH data cover the area much less wider in 3D space compare to DDH data. I would like to check the spatial consistency of Pb-Zn grade by statistics and variography analysis between DDH and BH. In this case is interesting also to discuss about change of support as the BH data have much closer spacing compare to DDH data, and BH result sludges/cuttings compare to DDH which result cores for assay data. I am performing the analysis for each rocktypes group (domain). I will be happy if anyone here in the list could share or suggest me any references related to this subject. Thank you for kind help and attention. Regards, --- M. Nur Heriawan Earth Resources Exploration Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40132 INDONESIA http://www.mining.itb.ac.id/heriawan + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: public domain software for reserve modeling and mine planning
Dear list, How are you doing? Hopefully everything is doing well. I would like to ask anybody if you could share some knowledges...are there any kind of public domain (open source) softwares for reserve modeling as well as for mine planning (design)? I know something like SGeMS perhaps can be used for reserve modeling (block model in 3D), but not for mine planning. Thank you for any comments. Best regards, --- M. Nur Heriawan Earth Resources Exploration Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40132 INDONESIA http://www.mining.itb.ac.id/heriawan Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: Global estimation on a domain of unknown geometry
Dear list, I would like to discuss with you about the case study given in Journel`s book of Mining Geostatistics, related to the Chapter V.C.4.: Global estimation on a domain of unknown geometry. The case study is regarding Ity deposit (p. 439 to 443) where the estimated block has different size: b1 (N-S direction) is 20 m and b2 (W-E direction) is 30 m. When we calculate the variance of global estimation, in p. 441 mentioned that in this case, the global estimation variance is calculated as the sum of a line term and section term. The line term (corresponding to the N-S lines which have the greatest data density, b1b2) measures the extension error of the 58 central accumulations to their segments (b1=20 m) of influence. My question is: what to do if we have the same data density, for example b1=b2...? which lines direction we should use to calculate the extension variance of points in lines term? The second case is still related to p. 441, mentioned that when we measure the extension variance of lines in rectangles term...the nugget effect has no influence, this is due to the fact that the nugget constant, regularized over the length L1 (for example), can be considered as zero because L1 is much greater than the diameter of the sampling pit, which is the support on which the constant C0 was defined. My question is: for which case (the rasio or comparison of the length of line and diameter of sampling pit) we should consider that the nugget is not zero? is there a rule of thumb for this case? I am waiting for any comments. Thank you. Regards, --- M. Nur Heriawan Earth Resources Exploration Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40132 INDONESIA http://www.mining.itb.ac.id/heriawan Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: geostatistics for vector estimation
Dear list, I am wondering if estimating kind of vector, i.e. fracture direction by using kriging or cokriging method is a proper way in geostatistics. We need opinion and references (if any) about this work. Thank you for attention. Regards, --- M. Nur Heriawan Laboratory of Applied Geoscience and Technology Graduate School of Science and Technology Kumamoto University, JAPAN http://www.civil.kumamoto-u.ac.jp/tansa Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for today's economy) at Yahoo! Games. http://get.games.yahoo.com/proddesc?gamekey=monopolyherenow + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: the importance of additiveness
Dear list, We know that additivity of the variables under study is the basic requirement of any geostatistical study. In practical term, geostatistic works on the variables defined on constant support. Therefore if our variables (i.e. grade) were derived from the different support (i.e. sample thickness or size), we should use the accumulation (product of thickness or size and the grade) before estimate it. Then the estimated grade is obtained by dividing the estimated accumulation by the estimated thickness or size. May someone has experience regarding the effect of ignoring additivity in any kind of geostatistical estimation compare to the estimation which considering additivity. In other word, how importance of this additivity in geostatistical estimation. Any opinions or references are very welcome. Thank you for attention. Kind regards, --- M. Nur Heriawan Laboratory of Applied Geoscience and Technology Graduate School of Science and Technology Kumamoto University, JAPAN http://www.civil.kumamoto-u.ac.jp/tansa Finding fabulous fares is fun. Let Yahoo! FareChase search your favorite travel sites to find flight and hotel bargains. http://farechase.yahoo.com/promo-generic-14795097 + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: ore grade and reserve estimation
Dear list, I am looking for some books about integrated reserve estimation and grade control (for mine planning). These books are for teaching purpose. From googling, I found two titles: - Ore Reserve Estimation and Strategic Mine Planning: Stochastic Models and Optimizations with Case Studies Dimitrakopoulos, Roussos Springer, 2006 Ore Reserve Estimation and Grade Control J.E. Gill The Canadian Institute of Mining and Met, 1968 - I did not find any reviews about these books. Therefore, before I order them, may somebody give the comment or suggestion. Thank you for kind attention, Regards, --- M. Nur Heriawan Laboratory of Applied Geoscience and Technology Graduate School of Science and Technology Kumamoto University, JAPAN http://www.civil.kumamoto-u.ac.jp/tansa __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: how to incorporate drilling and wireline logging data
Dear all, I need a reference on how to incorporate the drilling and wireline logging data. As we know that sometimes the informations of layers depth resulted from drilling and wireline logging are different, then for this case we need to incorporate them by considering a measurement error. Actually a few years ago I found a paper discussed about this, but I lost it, and I could not search it again. I appreciate any helps. Thank you. --- M. Nur Heriawan Laboratory of Applied Geoscience and Technology Graduate School of Science and Technology Kumamoto University, JAPAN http://www.civil.kumamoto-u.ac.jp/tansa Don't get soaked. Take a quick peak at the forecast with the Yahoo! Search weather shortcut. http://tools.search.yahoo.com/shortcuts/#loc_weather + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
AI-GEOSTATS: software for image analysis
Dear list, I am going to analyze and interpret the digital image obtained from X-Ray CT scanner. Hopefully someone could suggest me regarding a free software for such image analysis. Thank you for attention. Regards, --- M. Nur Heriawan Lab. of Applied Geosciences Tech. Kumamoto Univ., Japan __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
Re: AI-GEOSTATS: Coregionalization2
Hello Gonzalo, To fit your linear model of coregionalization, you could use a fortan program named LCMFIT2.FOR. You have to download it from IAMG official homepage. Please read the following article for detail explanation: Pardo-Iguzquiza, E. and P.A. Dowd.(2002), FACTOR2D: a computer program for factorial kriging. Computer Geosciences, Vol. 28, pp.857-875. Good luck! Nur H. --- [EMAIL PROTECTED] wrote: I am interested in a program for fitting a linear model of corregionalization for soil physical and chemical properties data. If some of you can give me some advices i woul be very please --- M. Nur Heriawan Lab. of Applied Geosciences Tech. Kumamoto Univ., Japan __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
RE: AI-GEOSTATS: covert binary grid to ASCII grid
Dear Bob, Thanks for response my mail and sorry for not giving a complete information. The format of binary grid file I have is .bgr In fact, I have tried to use the grid translator in GEODAS, but it failed. Regards, Nur H. --- bob sandefur [EMAIL PROTECTED] wrote: There are thousands of binary grid formats-Which one do you have? --- M. Nur Heriawan Lab. of Applied Geosciences Tech. Kumamoto Univ., Japan __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com + + To post a message to the list, send it to ai-geostats@jrc.it + To unsubscribe, send email to majordomo@ jrc.it with no subject and unsubscribe ai-geostats in the message body. DO NOT SEND Subscribe/Unsubscribe requests to the list + As a general service to list users, please remember to post a summary of any useful responses to your questions. + Support to the forum can be found at http://www.ai-geostats.org/
[ai-geostats] about cross-validation
Dear everyone, One of my colleague asked me about the mathematical equation of cross-validation method (leave-one-out method), and I said that it depends on the estimation method he used. He wants to know the general mathematical equation to define a cross-validation process. So far, in my experience, such method is performed just to check...which variograms model we used in (kriging) estimation are correct (valid). But cross-validation method should be used also to check the validation of any kind of estimation methods beyond kriging. May someone address me to a reference or book discussed in detail about cross-validation (leave-one-out) method, especially in mathematical point of view. Any kind of information related to this method is also appreciated. Many thanks for kind attention. Regards, Nur Heriawan Earth Resources Exploration Research Group Faculty of Earth Sciences and Mineral Technology Institut Teknologi Bandung (ITB), Indonesia http://www.isme-ix.org/ __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
[ai-geostats] software for 3D visualization
Hello everybody, I have 3D categorical output data in X, Y, and Z resulted from interpolation. I need a program or software for visualizing those data in 3D block model. I have used PIXELPLT (from GSLIB) to make any slices in XY, XZ, and YZ directions, but it could not be used for 3D block visualization. So, could anybody suggest me which free or comercial program (or software) I should use in this purpose? Thanks for your helps. Best regards, Nur Heriawan Earth Resources Exploration Research Group Institut Teknologi Bandung (ITB) Indonesia __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
Re: [ai-geostats] spherical model
Dear Isobel, Thanks for your reply. It is the first reply regarding this subject. Beforehand, I got one information mentioned that spherical model corresponds to a Random Function resulting of the summation of 3D spheres random in space, each sphere being given a value. Moreover, it is mentioned that there is no particular reason why this model should be used rather than another (positive definite) equation. But historically people have given preference to this model, and most (but not all) experimental semivariograms can be modeled by a combination of spherical. The information I got above is exactly matching with yours. Again thank you. Cheers, Nur H. --- Isobel Clark [EMAIL PROTECTED] wrote: Hi, I do not know whether you received any answers off-list, so here goes. The spherical model of geostatistics was so-named by Matheron and is sometimes also known as the Matheron model. His idea was that a sample has a 'sphere of influence' around it. Potential (or actual) samples within this sphere have values which are 'related' to the value at the central point. Imagine, now, a second such point with its own sphere of influence. If the spheres do not touch, there is no relationship between the values at the two central points. If the spheres overlap, there will be a relationship. The more the spheres overlap, the stronger the relationship. The spherical semi-variogram is the simple geometric calculation for the volume of NON-overlap of the two spheres, given the distance between their centres. There is no real reason why it should work in so many cases -- any more than there is for the Normal (Gaussian) distribution being found so often in nature. In fact, there is often a possibility to fit several of the semi-variogram models in practice. You could decide which is most appropriate using something like Cressie's goodness of fit test (analagous to a sort of chi-squared statistic). M. Nur Heriawan http://www.mining.itb.ac.id/heriawan __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
[ai-geostats] spherical model
Dear list, I have small query. Why almost all kind of spatial data set (ore grade data, sea surface temperature data, soil thickness, etc.) is fitted to the spherical (variogram) model? May anyone explain the origin of this spherical model? Thank you for your help. Regards, M. Nur Heriawan --- Graduate School of Science and Technology Kumamoto University Kurokami 2-39-1, Kumamoto 860-8555, JAPAN __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
[ai-geostats] fitting an ellipsoid model
Dear list, I am going to fit an ellipsoid model of anisotropy. The input are 4 ranges (scale parameters) and 4 main directions (0, 45, 90, 135 degree) from directional semivariogram model. Is there anybody have experience or a reference related to the algorithm for doing that? It is looked simple but make me confusing. I could do it by manual, but I want to obtain the precise ellipsoid anisotropy by writing a small routine. Many thanks for your attention. Regards, M. Nur Heriawan http://www.mining.itb.ac.id/heriawan __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
Re: [ai-geostats] autofitting variogram
Hello, The GSLIB itself gives the routine to draw a variogram model (vmodel), but unfortunately not by autofit. First, you have to define the fitting model, then set it into the parameter file in vmodel. Good luck Cheers, Nur Heriawan http://www.mining.itb.ac.id/heriawan --- samuel verstraete [EMAIL PROTECTED] wrote: Hello dear list, Is there anybody aware of software that can autofit a variogram to gslib output (gamv) gr, Samuel * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats Yahoo! Sports Rekindle the Rivalries. Sign up for Fantasy Football http://football.fantasysports.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
Re: [ai-geostats] Joint of two layer.
I did the same project 2 years ago using the same software. But on that time I worked with 2D variogram (of coal thickness). I think there is no direct relationship between the range of vertical variogram with the clay thickness, if the variogram you used was related to the coal thickness. OK made the smoothing in estimation result, that's why some parts of your intercalations were calculated as coal. This problem will be more clearly appeared if you have a nugget component in your variogram (of coal thickness). I think you can try to use other methods such as indicator kriging or conditional simulation. Cheers, Nur Heriawan http://www.mining.itb.ac.id/heriawan --- Tayfun Yusuf Yunsel [EMAIL PROTECTED] wrote: Dear list members, I am studying on a coal reserve calculation using OK procedure. I applied a 3D grid design to the composited data. So I have a horizontal and vertical variogram (two range). The grid size in the vertical direction is 4m and vertical variogram range is 16m. There are intercalations whose thickness varies between 0.50-6m in the coal layer. In the estimation process (OK), the clay layers (intercalations) were calculated as coal (due to clay thickness vertical variogram range). My question is that How can I seperate a thin intercalation layer (according to the coal layer (30-60m)) from the coal layer? Currently I am using the Isatis software. Thank you very much for your attention and time. Res. Assist. Tayfun Yusuf YNSEL Mining Engineering Department Engineering Faculty Cukurova University 01330, Balcali, Adana TURKEY * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
[ai-geostats] a linear coregionalization model
Dear All, I am working with a multivariate geostatistics. In determining whether the semivariogram or cross-semivariogram follows a linear coregionalization model or not...must the spatial range be the same? For instance, I have semivariogram and cross-semivariogram from 2 different variables as follow: gamma1(h) = 11 nug(h) + 39 sph(h/60) gamma1(h) = 9 nug(h) + 15 sph(h/100) gamma12(h)= 14.5 sph(h/80) If I consider only the variance-covariance components, such models follow the positive-semi definite condition. But how about the different spatial range I have in each semivariogram-cross semivariogram? Is it essential in a linear coregionalization model? Thank you for your attention. Regards, Nur Heriawan __ Do you Yahoo!? Yahoo! Small Business - Try our new resources site! http://smallbusiness.yahoo.com/resources/ * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
Re: [ai-geostats] Who is J. W. Merks???
Dear Perry, Please visit this website: http://www.geostatscam.com/index.htm You might know him better... :-) Regards, Nur Heriawan Dept. of Mining Eng. Institut Teknologi Bandung Jl. Ganesha 10 Bandung 40132 INDONESIA --- [EMAIL PROTECTED] wrote: Hi List I was searching for geostats books on www.amazon.com http://www.amazon.com and came across a reviewer by the name of J. W. Merks who has trashed every single geostatistical publication available. This is what he had to say about Geostatistics : Modeling Spatial Uncertainty (Wiley Series in Probability and Statistics) by http://www.amazon.com/exec/obidos/search-handle-url/index=booksfield-autho r=Jean-Paul%20%20Chil%E8s/103-9170296-4642251 Jean-Paul Chilès, http://www.amazon.com/exec/obidos/search-handle-url/index=booksfield-autho r=Pierre%20%20Delfiner/103-9170296-4642251 Pierre Delfiner : Geostatistics is a fatally flawed variant of mathematical statistics because it violates the requirement of functional independence and ignores the concept of degrees of freedom. Google bre-x bogus barren and look under Geostatistical Fiction to find out what the author and similarly challenged scholars know about degrees of freedom. Ironically, unbiased statistical inferences are impossible to obtain without taking degrees of freedom into account. The author has been asked to explain why the variance of a SINGLE distance-weighted average is replaced with the variance of a SET of distance-weighted averages. His reply will be posted ASAP. He said this about the GSLIB2 manual: Geostatistics is a fundamentally flawed variant of mathematical statistics because it violates the requirement of functional independence and ignores the concept of degrees of freedom. Each weighted average had its on variance wen Sir Ronald A Fisher was knighted in 1952 but when the distance-weighted average mutated into an honorific kriged estimate, it became the first and only weighted average to be reborn without its variance. Incredibly, kriging variances and kriging covariances of sets of kriged estimates are the cornerstones of geostatistics. Incredible indeed because the variance of a set of distance-weighted averages is as inane a measure for variability, precision and risk as its covariance is for spatial dependence. Hailed by pundits as a new science but dismissed by skeptics as a sham, geostatistics is applied to small data sets in large sample spaces by assuming spatial dependence, interpolation by kriging, perfect smoothing and rigging the rules of mathematical statistics. Statistics 101 ought to be compulsory for those who assume the requirement of functional independence can be violated a little but not a lot. Can anyone tell me what this guy is talking about? Is he a nutter? Does he need to get a life? Who is he anyway? Cheers Perry Perry Collier Senior Mine Geologist Ernest Henry Mine Xstrata Copper Australia * (07) 4769 4527 * (07) 4769 4555 * [EMAIL PROTECTED] http://www.xstrata.com http://www.xstrata.com/ PO Box 527 Cloncurry QLD 4824 Australia I like rich people. I like the way they live. I like the way I live when I'm with them... From Roger Hammerstein's Sound of Music __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com * By using the ai-geostats mailing list you agree to follow its rules ( see http://www.ai-geostats.org/help_ai-geostats.htm ) * To unsubscribe to ai-geostats, send the following in the subject or in the body (plain text format) of an email message to [EMAIL PROTECTED] Signoff ai-geostats
