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Changes psurvey.design Version 2.2.1 (12/31/05)
Download psurvey_changes2_2_1 (pdf 35 KB, 3 pp)
Version 2.2.1 (Released December 31, 2005)
Modified functions framesum and dsgnsum to print the output list plus labeling information to the console and to ensure that multidensity category (mdcaty) is not used for summarizing when the type of random selection (seltype) is equal to "Continuous" for any stratum.
Modified functions grts and irs to ensure that the variable which identifies panel names in the output object is created without error when the actual size of the sample is less than the desired size.
Modified function grts to ensure that argument att.frame contains valid values in the mdcaty column, which identifies the unequal probability category for each element in the frame.
Version 2.2 (Released November 30, 2005)
Created functions irs, irspts, irslin, and irsarea that implement independent random sample (IRS) survey designs for finite, linear, and area resources. Also, created C functions named linSampleIRS and getShapeBox that support creation of IRS survey designs.
Modified function grtsarea to remove sample points that failed to fall within the defined areal frame.
Created a C function named pickGridCells to select grid cells that get a sample point for GRTS survey designs. Previously, R code was used to select the grid cells.
Modified the C function ranho to replace use of the C function rand with the R function runif, which allows control over the random number generator seed that is used in the C function.
Version 2.1 (Released August 31, 2005)
Modified function summary.SurveyDesign to use an sp package object as input and renamed the function to dsgnsum. Also, renamed the function summary.SurveyFrame to framesum.
Modified function read.shape to output an sp package object.
Modified function grts to output an sp package object.
Modified the C function writeDbfFile to ensure that sufficient precision is used so that small values are not written as zero.
Modified function summary.SurveyDesign to eliminate summarizing by mdcaty (the unequal probability category for each element in the frame) when seltype (the type of random selection) is "Continuous".
Modified functions grts, grtspts, grtslin, and grtsarea to ensure that argument maxlev (the maximum number of hierarchical levels to use for the GRTS grid) does not exceed 12 and to define 12 as the default value for maxlev. Also, modified functions grtspts, grtslin, and grtsarea, and the C function numLevels to ensure that the initial number of hierarchical levels is at least one.
Modified function grts to ensure that the oversample is not included in the sample size for the weight adjustment calculation that occurs when an oversample is present.
Modified functions grtspts, grtslin, and grtsarea to correct an error that occurred when creating the randomized hierarchical address for grid cells.
Modified the three demonstration programs to improve clarity of the material that is presented.
Modified function grts to ensure that the values specified by caty.n (the vector of sample sizes for each category in mdcaty, which is required for each element of the design list for which the selection type is "Unequal") occur among the levels of mdcaty (the variable in the attributes data frame that specifies the unequal probability category for each element in the frame).
Modified function grts to obtain the stratum name from the design list when a design is unstratified.
Version 2.0 (Released April 30, 2005)
Created the following demonstration programs, i.e., programs invoked using the
demo function, that illustrate using the library to create survey designs:
(1) Finite - survey designs for a finite population (discrete points)
(2) Linear - survey designs for a linear resource
(3) Area - survey designs for an areal (polygonal) resource
Created an R method for summary applied to an object of class "SurveyFrame", i.e., an object created by the read.dbf and read.shape functions, that will print information regarding the frame and tables containing the cross-tabulation of extent for the survey design variables multidensity category (mdcaty), panel, and stratum plus an optional set of user-specified attributes.
Created an R method for summary applied to an object of class "SurveyDesign", i.e., an object created by the grts function, that will print information regarding the design and tables containing the cross-tabulation of number of sites for the survey design variables multidensity category (mdcaty), panel, and stratum plus an optional set of user-specified attributes.
Used the R and C programming languages to create a function that will read an ESRI GIS (ArcView) shapefile.
Used the R and C programming languages to create a function that will read the attribute (dbf) file of an ESRI GIS (ArcView) shapefile.
Modified the function selectpts (select a sample of size one or larger from a set of cells based on inclusion probabilities) to ensure that sample size does not exceed frame size. Note: selectpts is used for creating a survey design for a finite resource.
Modified the grts, grtspts, grtslin, and grtsarea functions so that names used in the output objects are consistent with expectations of the psurvey.analysis library.
Used the C programming language to create a function that calculates either the length or area, as appropriate, of each record in ArcView shapefiles of types linear and polygon.
Used the R and C programming languages to modify the library so that the user can control both the initial number of levels and the maximum number of levels of the survey design grid.
Used the R and C programming languages to replace numerical integration with intersection of polygons for calculating polygon area in each cell of the survey design grid.
Version 1.2 (Released November 30, 2004)
Modified the functions grtspts (GRTS sample of a finite resource) and grtslin (GRTS sample of a linear resource) and associated support functions to use the cell-based approach for sample selection that was used for function grtsarea.
Created C language support functions for grtspts, grtslin, and grtsarea.
Created C language functions that improved speed of the sample selection process and allowed creation of survey designs of larger size.
Created C language functions for reading and writing shapefiles.
Version 1.1 (Released August 31, 2004)
Created a function named grtsarea and associated support functions that added the capability to select a GRTS sample of an area resource.
Version 1.0 (Released April 30, 2004)
This is the original version of the library.