EVIEWS TUTORIALS Johnson P. Asiama (Dr.)

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Econometric Software • Software packages for econometric analyses:

– Autobox - Automatic Box-Jenkins (ARIMA and Transfer Function Modeling)

– EViews - Econometric Views

– GAUSS (software)

– gretl - Gnu Regression, Econometrics and Time-series Library

– OxMetrics - Ox Based Econometrics

– PcGive, see OxMetrics

– RATS - Regression Analysis of Time Series

– Stata - all purpose package

– SAS System - all purpose tool

– TSP - Time Series Processor, econometric package and programming language

– TSM (Time Series Modeling)

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EVIEWS - Getting Started

• Eviews window

• Creating a workfile

• Importing data

• View and plot data

• Run simple regression

• Performing basic tests

• Generate new variables

• Working with Commands 6/28/2011 3

1. Open Eviews Window

• Click on the Eviews icon

• Main Eviews window: title bar: at the top, inlcluding menus such as “File”, ”Edit”, etc.

command window: immediately below the title bar. You can execute commands either by clicking on command buttons or by typing equivalent command into the command window.

status line: at the bottom, providing additional information on the status of various settings of the program.

work area: between the command window and the status line, where the results of operations will be displayed.

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Eviews Window

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The Main Menu

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The Command Window

• Below the menu bar is an area called the command window. EViews commands may be typed in this window.

• The vertical bar in the command window is called the insertion point.

• It shows where the letters that you type on the keyboard will be placed.

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The Status Line

• At the very bottom of the window is a status line which is divided into several sections.

• The left section will sometimes contain status messages sent to you by EViews. These status messages can be cleared manually by clicking on the box at the far left of the status line

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The Work Area

• The area in the middle of the window is the work area where EViews will display the various object windows that it creates.

• Think of these windows as similar to the sheets of paper you might place on your desk as you work.

• The windows will overlap each other with the foremost window being in focus or active.

• Only the active window has a darkened titlebar.

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2. Creating a Workfile • Workfile: The most important object container

in Eviews, which can be used to store data and results.

• Create a workfile: Click on the File menu, then on New, and on Workfile

In the window appeared: 1) Choose the type of your data. For example, you can select

“Dated-regular frequency” for time-series data; 2) Input the start and end dates of your data; entering dates –

June 1997 to September 2010 will be entered as 1997:2 or 2010:3. First quarter of 1999 to June 2006 will be entered as 1999:1 2006:2, etc.

3) Name the workfile (optional). 4) Click OK.

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2. Creating a Workfile contd • The workfile now contains two entries:

• c – constant, where Eviews saves the intercept of the regression.

• resid – residuals, where Eviews saves the residuals of last regression

• You can then import data into this workfile.

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2. Creating a Workfile contd • Workfile

Central place to keep

all of your work

• Objects

– Series (Numeric or Alpha)

– Equations

– Graphs

– Groups

*Always comes with series for a constant, c, and residuals, resid

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2. Creating a Workfile Contd

• Creating a Workfile

– File → New → Workfile

• Data Structure

Time Series → Dated/Regular → Frequency + Date Range

Cross-Sectional → Undated/Unstructured → # of observations

Panel → Balanced Panel

• Save & Name

• New Pages

– By clicking on the “New Page” label at the bottom of the Workfile you can create new pages

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Exercise #1

• Open the Excel file Waifemtrial.csv. The file contains data on a number of macroeconomic variables of a country.

• Create a new Workfile in Eviews

• We now want to get the data into Eviews

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3. Importing Data • Import from excel file:

– Simply copy/cut and paste into EVIEWS, or – Open the file, make sure the observations for different

variables are arranged in columns, with names on top. Copy the names of the variables, and remember the Upper left data cell (location of first data, i.e., A2), then close the spreadsheet.

– In main Eviews window, after creating the workfile, click File, Import , then Read Text-Lotus-Excel, and specify the location of data file.

– In the opened dialog box, fill in the Upper left data cell, then paste the names of the variables, click OK.

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3. Importing Data contd • Enter data manually:

– click on Quick in the title bar, and then on Empty Group (Edit Series).

– Next enter the variables, starting with the name, in the grey box to the immediate right of “obs.”

• Import ASCII data from a textfile: – Make sure the observations for different variables are

arranged in columns, with names on top. – In the Eviews workfile window, click Procs, and Read

Text-Lotus-Excel, then browse for location the text file. – In the dialog box, select from a range of input options.

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3. Importing Data contd • Edit data: click the Edit+/- button on the

series toolbar, move to the observation in question, enter the correct value, and press Enter.

• Paste data into word file: click freeze, then you can copy and paste.

• Print data: click Print button. • Save data: Save an entire workfile: click Save in the workfile toolbar,

or click on File and then SaveAs in the main menu.

Store individual series: click Store in the workfile toolbar. If you need to retrieve the series, you can simply click on Fetch in the workfile toolbar.

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3. Importing Data

• Copy/Paste Method 1. Open new “Empty Group”

• Quick → Empty Group • Click on Cell 1 and press the “Up” arrow on keyboard

→

2. Open Excel

• Make sure variable names are one constant “String” (no spaces!)

• Troubleshoot for other problems

3. Copy Data 4. Paste into Eviews Cell 1 6/28/2011 18

3. Importing Data • Import Directly

1. Count the number of variables and CLOSE Excel file 2. Proc →Import →Read Text-Locus-File 3. Browse for Excel file 4.

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4. View and Plot Data-1 • View data

– One variable – double click on variable in workfile window, click on view, then spreadsheet;

– Multiple variables – in workfile window, select the name of variables needed, right click and choose “open selected/one window/open group”

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4. View and Plot Data-2 • Plot data

– One variable – double clicking on the name of the variable, then click on View /Graph/Line in the resulting series window.

– Multiple variables – open the variables as a group, then click View /Multiple Graph/Line.

– Edit: Right click on the graph or click on Options button to edit.

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5. Descriptive Statistics

• Group

– Stores select series together

– Object → New Object → Group → Select Series → Name

• Descriptive Statistics

– When group spreadsheet is open:

– View → Descriptive Statistics → Common Sample

→ Covariance

→ Correlations

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Exercise #2

• Create a group of variables

• Find the Standard Deviation for each variable

• Run a correlation matrix of independent variables to determine if you might have multicollinearity (hint: look if off-diagonal absolute values are bigger than 0.5)

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6. Generate New Variables

• In the workfile window, click Genr button, then specify the new variable using equation formula.

• Alternatively, in the command line, use command “genr” to generate new variables. For example,

– natural logs: genr lcpi=log(cpi)

– genr loilpq = loilp*loilp

– lagged variable: genr lprice=price(-1)

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7. Run Simple Regression-1 • In main Eviews window, click Quick, then

Estimate Equation. Alternatively, in Workfile window, click Object, and New Object, then click Equation.

• Equation Speciation: write down the equation, then choose the method (usually least squares) and sample period.

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7. Run Simple Regression-2

• Saving equation: using Name Option

• Note: If run linear regression, you may just input the name of the variables instead of the whole formula. First is the dependent variable, then write down all independent variables. (e.g: Y c X1 X2 … Xk)

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7. Run Simple Regression-3

• The interpretation of the coefficients:

– It indicates the effect of a unit change in the relevant variable on the dependent variable, holding all other factors constant (“ceteris paribus”).

• Exporting table of results:

– Save table using Freeze/Name

– Open table, select all, then copy and choose “formatted”, thus paste in word file.

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7. Run Simple Regression-4

• Test:

Click View/Coefficient Tests/Wald-Coefficient Restrictions.

• View results in the equation window:

Regression output: click View, then Estimation output

Residuals: click View, then Actual, Fitted redisual

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• Create a new Equation

– In your Workfile:

– Object → New Object → Equation

Separated by spaces: *Dependent variable *Constant, c *Independent variables (or Group)

8. Regression Tests and Fixes

Sample Range

Type of Regression

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• Output

• Name = Save to Workfile

8. Regression Tests & Fixes

Estimate: Modify Regression

This View

Useful to Create Model

To Run Tests

Regression Summary

Coefficient Summary

Statistics

SAVE!

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• Looking at Residuals

– In Equation View:

– View → Actual, Fitted, Residual → Actual, Fitted, Residual Table

• Plotting Resid Vs. Fitted Values

– Generate fitted values

– In Equation View: “Forecast” → OK (is named “variable”f)

– In Workfile: Object → New Object → Graph

• Graph: resid “variable”f

• Options → Type → Scatter

8. Regression Tests & Fixes

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• Heteroskedasticity

– In Equation View:

– View → Residual Tests → Heteroskedasticity Tests…

– Choose test

– Look at Chi-square value from a table

– Fix: Click on “Estimate” • Click on “Options” → check box for “Heteroskedasticity consistent

coefficient covarariance” → OK

8. Regression Tests & Fixes8.

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• Normality

– View → Residual Tests → Histogram-Normality Test

– Look at Jarque-Bera stat

– Fix: Depending on skew, you can adjust variables (ex: square, log, etc) or add/delete variables

8. Regression Tests & Fixes

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• Correlation & Multicolinearity

– Create Correlation Matrix:

– Select Group of independent variables

– View → Covariance Analysis… • Select “Correlations” (unselect “Covariance”)

– Off-diagonal values should be less than 0.5

– Fix: ?

8. Regression Tests & Fixes

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Exercise #3

• Plot fitted values vs. residuals

• Check for Heteroskedasticity and fix if necessary

• Check for Multicolinearity

• Check for Normality

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9. Changing/Creating Variables

• Edit Mode

– In Spreadsheet: Toggle “Edit+/-”

– CAREFUL! No “undo”

• Generate new variable

– In Workfile:

• Click on “Genr”

• Enter equation:

“new variable name” = equation

• Regular math function keys

• Lag: variable(-1)

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10. Commands

• Top, Left-Hand “Command Box”

• Single commands

• Batch (program)

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10. Commands

• Frequently Used Commands:

– show variable

– genr variable = equation

– sample n1 n2

• n1 and n2 represent the start and end of range

• Or qualifiers such that:

sample variable if >15

• Statistical Operations:

– equation name .ls(h) dependent c independent variables

– cor variables

– group variables

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Help!

• For general instruction or commands:

– EViews PDFs !

– Start → Programs → EViews6

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All Done! Practice, Practice, Practice and Practice!

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