# GS+ Featured Statistics

Spatial Autocorrelation Analysis

• Semivariance Analysis, including
• Isotropic and anisotropic (direction-dependent) variograms
• 4 types of isotropic and anisotropic variogram models
• Automatic model fitting, and / or user-specified
• Anisotropy maps, for quickly identifying anisotropy
• h-Scattergrams and Cloud variograms, for finding variogram outliers fast
• Other autocorrelation measures
• Correlograms
• Drift
• Covariograms
• Rodograms
• Standardized Variograms
• General Relative Variograms
• Pairwise Relative Variograms
• Moran’s I
• Fractal Analysis
• Cross-variogram analysis, for covariate analysis prior to co-kriging
• Full control over lag class (separation distance) intervals and extent

Interpolation

• Kriging, for optimal interpolation based on spatial dependence
• Block kriging, for interpolating a discrete area around interpolation points
• Punctual kriging, for interpolating discrete points
• Cokriging (both block and punctual), for more precise interpolations when a covariate is present
• Conditional Simulation
• Inverse and Normal Distance Weighting for classic nearest neighbor analysis
• Cross-validation (Jackknife) analysis, for comparing interpolated to known sample values
• Polygon masks of unlimited number and complexity
• Interpolation grids of any size
• 1D interpolation for temporal (time) data and linear transects
• Output compatible with ArcView® and other GIS and mapping programs (e.g. Surfer®)

Parametric Statistics

• Sample means and variance
• Skewness and kurtosis, for determining departure from normality
• Frequency distributions
• Normal probability plots
• Cumulative frequency plots
• Frequency histograms
• Transformations for returning the data to normality
• Quantile scattergrams, to display values for sampled locations
• Regression analysis (variate vs. covariate)

Mapping

• 2D and 3D projections of maps
• 1D graphs for transects and temporal data
• Maps of kriging estimation error
• Zata postings
• Full control of size, axis labels, colors, contour intervals
• Rotation and zooming

Data Handling

• Integrated data worksheet
• Huge data capacity – up to 2 billion records x 64 fields/columns
• Assign x, y, z, z2 columns easily among 64 possible columns
• Flexible input formats
• GeoEas, ArcView, Surfer formats
• Excel, DBase, Access files
• ASCII text files in user-defined format
• Flexible output formats
• ArcView, Surfer interpolation output formats for interpolation
• Graphics printed to any Windows device
• JPEG, GIF, PNG, Metafile graph output formats
• Missing values
• Permanent missing values handled gracefully
• Temporary missing values toggled on and off by user
• Data filter to exclude data ranges