search for: sediments

Displaying 20 results from an estimated 22 matches for "sediments".

Did you mean: sediment
2012 Sep 18
2
Formula in a data-frame
Hello all, I'm new in R, and I have a data-frame like this (dput information below): Specie Fooditem Occurrence Volume 1 Schizodon vegetal 1 0.05 2 Schizodon sediment 1 0.60 3 Schizodon vegetal 1 0.15 4 Schizodon alga 1 0.05 5 Schizodon sediment 1 0.90 6 Schizodon
2012 Oct 19
1
Optimization in R similar to MS Excel Solver
Dear Colleagues, I am attempting to develop an optimization routine for a river suspended sediment mixing model. I have Calcium and Magnesium concentrations (%) for sediments from 4 potential source areas (Topsoil, Channel Banks, Roads, Drains) and I want to work out, based on the suspended sediment calcium and magnesium concentrations, what are the optimal contributions from each source area to river suspended sediments. The dataset is as follows:...
2013 Jan 16
1
Mean calculation by two variables
Hello All, I have a data frame (dput information below) with food item weight for fish species. I need to calculate the Mean proportion by weight of each food item for each specie, as show in solution data frame (dput information below). I use the ddply function (plyr package) in two steps. First calculate the proportion of weight for each individual: step1 = ddply (example, .(ID), transform,
2005 Apr 13
1
barplot usage
Hi, I?m trying to make a barplot with the following dataframe, with information on relative frequency per sediment type (ST) for some species: Species ST1 ST2 ST3 SP_A 10 60 30 ... At x-axis are (should be ...) the species names and at y-axis the frequency per sediment, in stacked bars. I tried to use barplot command but with no results. Could anyone help me on this? Thanks in
2005 Jun 01
0
StructTS and arima and missing values
Dear List, I am thinking about ways in which I might analyse some stratigraphic data. The nature of the data series I have generates a number of issues: 1) The data I have in mind come from a sediment core sequence taken from the bottom of a lake. The sequence is sliced into a priori defined slices, in this case 0.2cm per slice. in this way a sequence of 0.2cm slices is produced for the
2011 Dec 30
3
vertically stacked area plot?
Dear all, I would like to create a vertically stacked area chart in R. The data are presented in the attached text file. I would like to see the trend in values for the different groups with sediment depth (that's why I would like to create a vertically stacked chart; normally sed_depth should be = x, but I want it plotted on the y-axis). In the packages available to create stacked area
2010 Oct 13
2
vertical kites in KiteChart (plotrix)
Dear everyone, I would like to create a kite chart in which I plot densities (width of the vertical kites) in relation to sediment depth (on reversed y-axis) for 6 different locations (Distances from seep site, on x-axis on top of the plot). The dataset I would like to use is: Distance_from_seep_site Sedimentdepth Density 1100 0 107.8 1100 1 264.6 1100 2 284.2
2010 Dec 21
2
please Help me on a repeated measures anova
I currently work on a draft of an aquatic bioassessment. The conditions tested are the following: ER river water T dechlorinated water control 0.5 + 0.5mg / L of malate T + 1 dechlorinated water control + 1g / L of malate T ED dechlorinated water control SED + ER + river water sediment SED ED + sediment + water dechlorinated. It is the result of AChE in muscle (fillet of fish). The production of
2009 Feb 03
1
axes
Hello there, Is there a functionality or command that generates axes in the shape of a capital Greek letter gamma (upside down L) ? I use these for making sediment profiles. I have read through help-lists, tried different things and asked several people but never got a satisfactory result. I've tried the following: xx <- c(2,4,6,5.8,5,4,3,1.5,0, 0, 0, 0) yy <- (0:-11) plot(NULL,
2011 May 27
1
continuous time AR(1)
Dear R helpers, I would like to model temporal trend of biological remains in sediment cores. All samples are temporally auto-correlated and I would like to take this effect into account. Initially I thought that I could use AR(1) or ARIMA functions but these functions only work with regular temporal intervals between samples. Hence I would like to use a continuous time AR(1) that allow
2007 Feb 27
3
rpart minimum sample size
Is there an optimal / minimum sample size for attempting to construct a classification tree using /rpart/? I have 27 seagrass disturbance sites (boat groundings) that have been monitored for a number of years. The monitoring protocol for each site is identical. From the monitoring data, I am able to determine the level of recovery that each site has experienced. Recovery is our
2004 May 24
2
Tramo-seats
Working - among other things- in the field of (short & long term) electricity forecast, we are now using too many & too expensive pieces of licensed software: SAS, SPSS, EViews. This "sedimentation" is due to the fact that my predecessors in the past used different consultant companies to manage each procedure. Having attended the useR2004! Conference with the aim of assessing
2011 Aug 24
1
R (&stats) newcomer.... help!
Hi all, I hope that i've posted this in the correct place. if not, please accept my apologies (where should this go?) I have carried out experimental removal of bivalves at 2 intertidal shores. Bivalves were removed by raking of surface sediments. I wish compare the biomass values of for a total of 8 species between the 2 shores My 3 treatments are: Undisturbed Controls (Cont), Procedural Controls (Proc) and Experimetnally Fished (Fished). As Fished and Proc have both experienced disturbance, I set the model using 2 factors as follows:...
2013 Feb 20
0
Bayesian mixing model
Fellow R users, I'm using the BCE {BCE} function to run a Bayesian sediment mixing model. The aim is to find the optimum % contribution from each of the 4 source areas that can yield the target geochemistry. I have geochemistry for 4 source areas called Rat: Rat<-read.table(text="CaO MgO Na2O Al2O3 Topsoils 2.511250 0.7445500 0.7085500 14.10375 ChannelBanks
2007 Nov 14
1
reading tables from url
...13694 Global Ocean Sampling Expedition Metagenome 2 20823 13696 5-Way (CG) Acid Mine Drainage Biofilm Metagenome 3 - 13699 Waseca County Farm Soil Metagenome 4 - 13702 Methane-Oxidizing Archaea from Deep- Sea Sediments 5 - 13729 Pacific Beach Sand Metagenome Thanks for your help. Hopefully this is something simple that I missed in the documentation/help. Chris -- ------------------- Chris Stubben Los Alamos National Lab BioScience Division MS M888 Los Alamos,...
2010 Mar 24
3
help in matlab - r code
Dear list members, I need to translate 3 lines of matlab code to R (a loop, to be specific), and I don't know what would be the results in matlab or how to do it in R-- I don't realise if they are doing to the col, vector or what. if the results are a vector or a value or a matrix :-( Anyone with matlab, can run it and give me the result? Any ideias what am I doing wrong? The code is
2003 Jun 03
0
GLM(...,start,...) question
I am trying to use the glm.nb proceedure in the new MASS library. I have count data (of snails) taken from a number of habitats (artesian springs). I want to model the abundances, including an effect of the organic content of the sediment. When I try to fit a model like: nb.model.p <- glm.nb(abundance~Organics.per.wt) I get the error message: Error: no valid set of coefficients has been
2007 Feb 16
2
cluster analysis under contiguity constraints with R ?
Hello, I would like to know if there is a function in an R library that allows to do cluster analysis under contiguity constraints ? Thank you very much for your answer ! Lise Bellanger -- Lise Bellanger, Universit? de Nantes D?partement de Math?matiques, Laboratoire Jean Leray UMR CNRS 6629 2, Rue de la Houssini?re BP 92208 - F-44322 Nantes Cedex 03 T?l. : (33|0) 2 51 12
2010 Dec 29
2
HELP for repeated measure ANCOVA with varying covariate
Dear All, I am a researcher doing research in plant growth and I have a statistical problem that seems to not be able to handle. Recently, I conducted an experiment about plant growing in three different nutrient-level sediments. I harvested these every three week (three harvests in all). Some growth traits of these plants were recorded (e.g. total biomass, leaf biomass and stem biomass). In addition, I found that the total plant biomass may also influence these traits. So, I am going to use total biomass as covariate...
2012 Oct 21
1
Linear discriminant function analysis based median as group centroid and nonparametric scale estimators???
Dear All, I am using a specific approach for my master thesis. In essence, a supervised reclassification is used as an intermediate step to find chemical parameters which are able to reclassify defined groups. These variables will be used in a next step where location and scale estimators of the groups are important. Traditionally linear discriminant analysis is used for reclassification which