METplus Practical Session Guide (Version 5.0) | Session 3: Analysis Tools > MET Tool: Stat-Analysis

Stat-Analysis Tool: General

Stat-Analysis Functionality

The Stat-Analysis tool reads the ASCII output files from the Point-Stat, Grid-Stat, Wavelet-Stat, and Ensemble-Stat tools. It provides a way to filter their STAT data and summarize the statistical information they contain. If you pass it the name of a directory, Stat-Analysis searches that directory recursively and reads any .stat files it finds. Alternatively, if you pass it an explicit file name, it'll read the contents of the file regardless of the suffix, enabling it to the optional _LINE_TYPE.txt files. Stat-Analysis runs one or more analysis jobs on the input data. It can be run by specifying a single analysis job on the command line or multiple analysis jobs using a configuration file. The analysis job types are summarized below:

  • The filter job simply filters out lines from one or more STAT files that meet the filtering options specified.
  • The summary job operates on one column of data from a single STAT line type. It produces summary information for that column of data: mean, standard deviation, min, max, and the 10th, 25th, 50th, 75th, and 90th percentiles.
  • The aggregate job aggregates STAT data across multiple time steps or masking regions. For example, it can be used to sum contingency table data or partial sums across multiple lines of data. The -line_type argument specifies the line type to be summed.
  • The aggregate_stat job also aggregates STAT data, like the aggregate job above, but then derives statistics from that aggregated STAT data. For example, it can be used to sum contingency table data and then write out a line of the corresponding contingency table statistics. The -line_type and -out_line_type arguments are used to specify the conversion type.
  • The ss_index job computes a skill-score index, of which the GO Index (go_index) is a special case. The GO Index is a performance metric used primarily by the United States Air Force.
  • The ramp job processes a time series of data and identifies rapid changes in the forecast and observation values. These forecast and observed ramp events are used populate a 2x2 contingency table from which categorical statistics are derived.

Stat-Analysis Usage

View the usage statement for Stat-Analysis by simply typing the following:

stat_analysis
Usage: stat_analysis  
  -lookin path Space-separated list of input paths where each is a _TYPE.txt file, STAT file, or directory which should be searched recursively for STAT files. Allows the use of wildcards (required).
  [-out filename] Output path or specific filename to which output should be written rather than the screen (optional).
  [-tmp_dir path] Override the default temporary directory to be used (optional).
  [-log file] Outputs log messages to the specified file
  [-v level] Level of logging
  [-config config_file] | [JOB COMMAND LINE] (Note: "|" means "or")
  [-config config_file] STATAnalysis config file containing Stat-Analysis jobs to be run.
  [JOB COMMAND LINE] All the arguments necessary to perform a single Stat-Analysis job. See the MET Users Guide for complete description of options.

At a minimum, you must specify at least one directory or file in which to find STAT data (using the -lookin path command line option) and either a configuration file (using the -config config_file command line option) or a job command on the command line.