| Gretl Manual: Gnu Regression, Econometrics and Time-series Library | ||
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Reading left to right along the main window's menu bar, we find the File, Utilities, Session, Data, Sample, Variable, Model and Help menus.

: Open a native gretl data file or import from other formats. See Chapter 4.
: Add data to the current working data set, from a gretl data file, a comma-separated values file or a spreadsheet file.
: Save the currently open native gretl data file.
: Write out the current data set in native format, with the option of using gzip data compression. See Chapter 4.
: Write out the current data set in Comma Separated Values (CSV) format, or the formats of GNU R or GNU Octave. See Chapter 4 and also Appendix D.
: Clear the current data set out of memory. Generally you don't have to do this (since opening a new data file automatically clears the old one) but sometimes it's useful (see the Section called Creating a data file from scratch in Chapter 4).
: See the Section called Binary databases in Chapter 4 and the Section called Creating a data file from scratch in Chapter 4.
: Initialize the built-in spreadsheet for entering data manually. See the Section called Creating a data file from scratch in Chapter 4.
: Open a window containing a record of the commands executed so far.
: Open a file of gretl commands, either one you have created yourself or one of the practice files supplied with the package. If you want to create a command file from scratch use the next item, .
: Set the paths to various files gretl needs to access. Choose the font in which gretl displays text output. Select or unselect "expert mode". (If this mode is selected various warning messages are suppressed.) Activate or suppress gretl's messaging about the availability of program updates. Configure or turn on/off the main-window toolbar. See Chapter 12 for details.
: Quit the program. If expert mode is not selected you'll be prompted to save any unsaved work.
: Look up critical values for commonly used distributions (normal or Gaussian, t, chi-square, F and Durbin–Watson).
: Open a window which enables you to look up p-values from the Gaussian, t, chi-square, F or gamma distributions. See also the pvalue command in Chapter 13.
: Calculate test statistics and p-values for a range of common hypothesis tests (population mean, variance and proportion; difference of means, variances and proportions). The relevant sample statistics must be already available for entry into the dialog box. For some simple tests that take as input data series rather than pre-computed sample statistics, see "Difference of means" and "Difference of variances" under the Data menu.
: Open a "console" window into which you can type commands as you would using the command-line program, gretlcli (as opposed to using point-and-click). See Chapter 13.
: Start R (if it is installed on your system), and load a copy of the data set currently open in gretl. See Appendix D.
: Check the numerical accuracy of gretl against the reference results for linear regression made available by the (US) National Institute of Standards and Technology.
: Open a window showing the current gretl session as a set of icons. For details see the Section called The Session concept in Chapter 3.
: Open a previously saved session file.
: Save the current session to file.
: Save the current session to file under a chosen name.
: pops up a window with a simple (not editable) printout of the values of the variables (either all of them or a selected subset).
: pops up a spreadsheet window where you can make changes, add new variables, and extend the number of observations.
: Rearrange the listing of variables in the main window, either by ID number or alphabetically by name.
: Gives a choice between a time series plot, a regular X–Y scatter plot, an X–Y plot using impulses (vertical bars), an X–Y plot "with factor separation" (i.e. with the points colored differently depending to the value of a given dummy variable), boxplots, and a 3-D graph. Serves up a dialog box where you specify the variables to graph. See Chapter 8 for details.
: Show a collection of (at most six) pairwise plots, with either a given variable on the y axis plotted against several different variables on the x axis, or several y variables plotted against a given x. May be useful for exploratory data analysis.
, : "Read info" just displays the summary information for the current data file; "Edit info" allows you to make changes to it (if you have permission to do so).
: opens a window containing a full account of the current dataset, including the summary information and any specific information on each of the variables.
: shows a fairly full set of descriptive statistics for all variables in the data set.
: shows the pairwise correlation coefficients for the variables in the data set.
: calculates the t statistic for the null hypothesis that the population means are equal for two selected variables and shows its p-value.
: calculates the F statistic for the null hypothesis that the population variances are equal for two selected variables and shows its p-value.
gives a sub-menu of standard transformations of variables (logs, lags, squares, etc.) that you may wish to add to the data set. Also gives the option of adding random variables, and (for time-series data) adding seasonal dummy variables (e.g. quarterly dummy variables for quarterly data). Includes an item for seeding the program's pseudo-random number generator.
Sometimes gretl commands generate new variables. The "refresh" item ensures that the listing of variables visible in the main data window is in sync with the program's internal state.
: Select a different starting and/or ending point for the current sample, within the range of data available.
: self-explanatory.
: invokes a series of dialog boxes which allow you to change the structural interpretation of the current dataset. For example, if data were read in as a cross section you can get the program to interpret them as time series or as a panel. See also Chapter 7.
: For time-series data of higher than annual frequency, gives you the option of compacting the data to a lower frequency, using one of four compaction methods (average, sum, start of period or end of period).
: Given a dummy (indicator) variable with values 0 or 1, this drops from the current sample all observations for which the dummy variable has value 0.
: Similar to the item above, except that you don't need a pre-defined variable: you supply a Boolean expression (e.g. sqft > 1400) and the sample is restricted to observations satisfying that condition. See the help for genr in Chapter 13 for details on the Boolean operators that can be used.
: Drop from the current sample all observations for which at least one variable has a missing value (see the Section called Missing data values in Chapter 4).
: Give a report on observations where data values are missing. May be useful in examining a panel data set, where it's quite common to encounter missing values.
: Set a numerical value that will be interpreted as "missing" or "not available".
: Prompts for the name of a text file containing "case markers" (short strings identifying the individual observations) and adds this information to the data set. See Chapter 4.
: Allows the conversion of a panel data set in stacked cross-section form into stacked time series or vice versa. (Unlike the menu item above, this one actually changes the organization of the data.)
Most items under here operate on a single variable at a time. The "active" variable is set by highlighting it (clicking on its row) in the main data window. Most options will be self-explanatory. Note that you can rename a variable and can edit its descriptive label under "Edit attributes". You can also "Define a new variable" via a formula (e.g. involving some function of one or more existing variables). For the syntax of such formulae, look at the online help for "Generate variable syntax" or see the genr command in Chapter 13. One simple example:
foo = x1 * x2will create a new variable
foo as the product of the existing
variables x1 and x2.
In these formulae, variables must be referenced by name, not
number.For details on the various estimators offered under this menu please consult the Section called Estimators and tests: summary in Chapter 13 and Chapter 13 below, and/or the online help under "Help, Estimation". Also see Chapter 9 regarding the estimation of nonlinear models.
Please use this as needed! It gives details on the syntax required in various dialog entries.