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Sophisticated Data Management
Powerful
analytic tools are only useful if you can easily work with your data.
EViews provides the widest range of data management tools available in
any econometric software. From its extensive library of mathematical,
statistical, date, string, and time series operators and functions, to
comprehensive support for numeric, character, and date data, EViews
offers the data handling features you’ve come to expect from modern
statistical software.
Extensive Function Library
EViews includes an extensive library of functions
for working with data. In addition to standard mathematical and
trigonometric functions, EViews provides functions for descriptive
statistics, cumulative and moving statistics, by-group statistics,
special functions, specialized date and time series operations,
workfile, value map, and financial calculations.
EViews also provides random number generators (Knuth, L'Ecuyer or
Mersenne-Twister), density functions and cumulative distribution
functions for eighteen different distributions.These may be used in
generating new series, or in calculating scalar and matrix expressions.
Sophisticated Expression Handling
EViews' powerful tools for expression handling
mean that you can use expressions virtually anywhere you would use a
series. You don't have to create new variables to work with the
logarithm of Y, the moving average of W, or the ratio of X to Y (or any
other valid expression). Instead, you can use the expression in
computing descriptive statistics, as part of an equation or model
specification, or in constructing graphs.
When you forecast using an equation with an expression for the
dependent variable, EViews will (if possible) allow you to forecast the
underlying dependent variable and will adjust the estimated confidence
interval accordingly. For example, if the dependent variable is
specified as LOG(G), you can elect to forecast either the log or the
level of G, and to compute the appropriate, possibly asymmetric,
confidence interval.
Links, Formulas and Values Maps
Link objects
allow you to create series that link to data contained in other
workfiles or workfile pages. Links allow you to combine data at
different frequencies, or match merge in data from a summary page into
an individual page such that the data is dynamically updated whenever
the underlying data change. Similarly, within a workfile, formulas can
be assigned to data series so that the data series are automatically
recalculated whenever the underlying data is modified.
Value labels (e.g., "High", "Med", "Low", corresponding to 2, 1, 0) may
be applied to numeric or alpha series so that categorical data can be
displayed with meaningful labels. Built-in functions allow you to work
with either the underlying or the mapped values when performing
calculations.
Data Structures and Types
EViews can handle complex data structures, including regular and irregular dated data, cross-section data with observation identifiers, and dated and undated panel data.
In addition to numerical data, an EViews workfile can also contain alphanumeric (character string) data, and series containing dates, all of which may be manipulated using an extensive library of functions.
EViews also provides a wide range of tools for working with datasets
(workfiles), data including the ability to combine series by complex
match merge criteria and workfile procedures for changing the
structure of your data: join, append, subset, resize, sort, and reshape
(stack and unstack).
File Import and Export
Exchanging data with other programs is easy, since EViews reads and writes over 20 popular data formats
(including Excel, formatted and unformatted ASCII/Text, SPSS, SAS
(transport), Stata, SPSS, Html, Microsoft Access, Gauss Dataset,
Rats, GiveWin/PC Give, TSP, Aremos, dBase, Lotus, and binary files).
Simply drag-and-drop your foreign file onto EViews and your data will
automatically appear in an EViews workfile. Or use the easy-to-use
dialogs and wizards to cutomize the importing of your data.
EViews Databases
EViews provides sophisticated built-in database features.
An EViews database is a collection of EViews objects maintained in a
single file on disk. It need not be loaded into memory in order to
access an object inside it, and the objects in the database are not
restricted to being of a single frequency or range. EViews databases
offer powerful query features which can be used to search through the
database for a particular series or select a set of series with a
common property.
Series contained in EViews databases may be copied (fetched) into a workfile, or they may be accessed and used
by EViews procedures without being fetched into workfiles. In both
cases, EViews will automatically perform frequency conversion if
necessary. Automatic search capabilities allow you to specify a list of
databases to be searched when a series you need cannot be found in the
current workfile.
Frequency Conversion
When
you import data from a database or from another workfile or workfile
page, it is automatically converted to the frequency of your current
project.
EViews offers many options for frequency conversion,
and includes support for the conversion of daily, weekly, or
irregular-frequency data. Series may be assigned a preferred conversion
method, allowing you to use different methods for different series
without having to specify the conversion method every time a series is
accessed.
You can even create links so that the frequency converted data series
are automatically recalculated whenever the underlying data is modified.
© Copyright 2009 QMS


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