Recodes, dummy variables, and product terms can be generated temporarily within the program itself, so that the user will not have to create such variables before running a regression.
Ordinarily this program is invoked by the Web interface for the SDA programs, and the user does not have to deal with the keywords given in this document. Output from the program is in HTML, which can be viewed with a Web browser.
It is also possible to run the program directly by preparing a batch command file, which specifies the variables to be analyzed and the options to use. This document explains how to prepare such a file. The name of this batch command file is specified to the program after the `-b' option flag.
Keyword Possible Specification Default (if no keyword) _____________________________________________________________________ STUdy= path(s) of dataset(s) Look for variables in the current directory only DEP= name of dependent variable REQUIRED INDep= names of independent vars REQUIRED (separated by spaces/commas) Weight= name of weight variable No weighting Filter= name(s) and codes of filter No filter variable(s) STRatum= name of variable giving No stratification for sample stratum computing standard errors $1: Force one stratum CLuster= name of variable giving No cluster variable for sample cluster computing standard errors NDECimals= number of decimals for main 3 decimal places results (coefficients, SE's) SAvefile= filename to receive output Output sent to screen (overwrite existing file) (standard output) DUMMYgenmax= A number between 1 and 100 Max of 25 dummy vars can be (max dummy vars) generated by the "m:" syntax for a single categorical var GVARCase= LOWER or UPPER No force to lower/upper case
Keyword Possible Specification Default (if no keyword) _____________________________________________________________________ COLORcoding= Yes No color coding of cells or colored headings LAnguagefile= Name of file with non-English English labels on labels and messages output RUNtitle= Title or comments for run No title or comments SHORTlist= Yes (omit list of Output list of all indep vars at top) independent variables TExt= Yes No text for variables
Note that the `otherstats=' keyword can be repeated on subsequent lines if necessary.
Keyword Possible Specification Default (if no keyword) _____________________________________________________________________ OTHERstats= TTests (ndec) No T-tests FTest (ndec) No Global F-test UNIvariate (ndec) No univariate stats BPRODuct (ndec) No B*coefficent stats CORel (ndec) No correlation matrix COVar (ndec) No covariance matrix COEFF (ndec) No covar of coefficients matrix CONF (90, 95, or 99) No confidence intervals ('CONF' alone gives 95% CI)
The statistic charted is each regression coefficient and its confidence interval.
Keyword Possible Specification Default (if no keyword) _____________________________________________________________________ TBLProperties= PATHNAME for chart properties REQUIRED for charts file Required location for SDA 4 is: SDAROOT/tmpdir/xxx.cht where 'SDAROOT' is the pathname of the SDA installation on your server, and where 'xxx' is any name. (See the last example below) (This is a temporary filename, to be passed on to the charting servlet.) CH_URL= URL of chart-generation REQUIRED for charts servlet on the server. Required URL for SDA 4 is: http://SDAURL/sdaweb/charts where 'SDAURL' is the hostname of the SDAWEB application on your server. (See the last example below) CH_COEFF= Coefficient to chart none (B or BETA or NONE) CH_INDEPVARSmax=Number of independent vars all to include in the chart (first N variables, where N is an integer) CH_RANGEOPT= Set the range of the chart auto either to: AUTO (set by the program) or CUSTOM (use specified low/high) if CH_RANGEOPT=CUSTOM, the following two options can be used: CH_RANGELOW= Lower bound of the range (can have decimals) CH_RANGEHIGH= Upper bound of the range (can have decimals) CH_FONT= Font to use in the chart SansSerif CH_WIdth= Width of chart in pixels 600 CH_HEight= Height of chart in pixels 400
For the other (optional) statistics, the default numbers of decimals are as follows:
This appending feature applies to the keywords for specifying the independent variables, the filter variables, and the 'otherstats=' keyword. It also applies to the 'study=' keyword, for specifying the locations of the SDA dataset directories. If other keywords are repeated, the program will print an error message and stop.
dep = spend indep = age, educ gender savefile = myregress.htm
Also request descriptive text for the variables.
dep = spend indep = age(18-30) educ gender weight= wtvar filters= var21(1-3) var30(1) text = yes savefile = myregress.htm
dep = spend indep = age, educ gender stratum = stratvar cluster = psuvar savefile = myregress.htm
Also request some optional statistics, most with a specified number of decimals.
study = /sa/testdata study = /sa/testdata/newvars dep = spend indep = age educ gender recodedvar otherstats = ttests ftest(4) univar(3) correl(3) savefile = myregress.htm
study = /sa/sdatest dep = vardep indep = spend1 spend2 spend3 spend4 age educ gender tblproperties = /var/www/sda/tmpdir/testing.cht ch_url=http://sda.berkeley.edu/sdaweb/charts ch_coeff = beta ch_indepvarsmax = 4 ch_rangeopt = custom ch_rangelow = -1.0 ch_rangehigh = 1.0 savefile = mymeans.htm