home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
CD ROM Paradise Collection 4
/
CD ROM Paradise Collection 4 1995 Nov.iso
/
science
/
simst35.zip
/
INSTALL._D2
/
INTRO.DOC
< prev
next >
Wrap
Text File
|
1994-05-07
|
23KB
|
461 lines
QUICK START
Startup Options
~~~~~~~~~~~~~~~
Three startup options are available to change the SIMSTAT default
settings. The following command line switches can be typed
following the program name when calling SIMSTAT:
/M (or -M) forces the program to run in black and white mode
rather than in color. This option is useful for use with a laptop
computer, or on a desktop computer with a monochrome or composite
monitor set on a color graphic adapter (CGA, EGA or VGA).
/E (or -E) sets the display to 43 lines on an EGA, or 50 lines
on a VGA graphics card.
/C (or -C) instructs SIMSTAT to use a compression procedure to
reduce the size of the output file sent to disk. This option is
useful for saving disk space when running SIMSTAT on a laptop, or
on a computer with limited disk space. The compressed output file
will take up to 75% less disk space than uncompressed. You can
browse through the listing file from within SIMSTAT; however you
cannot print or view this file outside the program. In order to do
this, you must first uncompress the file with the EXPAND.EXE
utility (see Appendix C).
/X (or -X) suppress the introductory screen.
You can use the SET command at DOS to include any of the above
options automatically when you start SIMSTAT. For example, the
following command:
SET SIMSTAT=/M
will cause the program to automatically run in black and white
mode.
Orientation through the screen
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
When you call up SIMSTAT, the first screen you see is the
introductory screen with product- version information. Pressing
any key will make this screen disappear and bring you to the
working screen (see figure 1) which is divided into three different
parts:
1) The main menu at the top of the screen gives access to
six pulldown menus from which commands can be invoked.
2) The status panel, located at the bottom of the screen,
displays information about the program's operation. This panel is
divided into three parts: The left side of the status panel
displays special function keys that can be pressed. The middle part
provides information about the destination of computer output
(printer or disk). The right side of the status panel displays the
data file name and the amount of memory available for analysis.
3) The central part of the screen is the output window, used
to display the results of your analysis.
Working with pulldown menus
~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following are basic instructions to help you navigate through
the menu system:
- To choose a menu command, type the first capital letter of the
command name. You can also use the <right arrow> or <left arrow>
keys to move to the command and press <Enter>.
- Once in a main menu, select a sub-menu command by typing the
first capital letter of the command name. You can also use the
<Up> and <Dn> arrow keys highlight the command and press <Enter> to
select your choice. Use the <right arrow> or <left arrow> keys to
move from one pulldown menu to another.
- You can press the <Home> key to go directly to the first
command on the menu or the <End> key to go to the last command.
- Press <Esc> to close pulldown menus.
Function keys
~~~~~~~~~~~~~
Some function keys provide quick access to often used commands. In
general, these keys can be activated from anywhere in the program.
<F1> Press the <F1> key to obtain context-sensitive help.
<F2> Pressing this key allows you to browse through the result
of analysis. The scope of action of this key depends on
whether or not the results are sent to disk. If the
listing is saved on disk, you will be able to browse
through the entire output file. If the disk log is off,
this key allows you to browse only through the results of
the most recent analysis.
<F3> Pressing this key allows you to select dependent and
independent variables (as shortcut for CHOOSE X-Y).
<F4> Pressing this key allows you to call an external text
editor in order to edit the output file. (See p.25 for
instruction on how to install a text editor).
<F6> Pressing this key makes SIMSTAT to pause between screens
of output.
<F7> Pressing this key toggles the printer log ON and OFF.
<F8> Toggles disk log ON and OFF (as shortcut for I/O
OPTIONS).
<F9> Pressing this key sends a formfeed to the printer. Use
this command to make sure that the next printing will
begin at the top of a new page. This command works only
if the printer log is ON.
<Esc> Pressing the <Esc> key cancels any operation in progress
(leaves a submenu or an options panel, aborts field
editing, interrupts statistical computation, etc.).
<F10> The <F10> key is often used to confirm the editing of a
panel and to proceed with the chosen command.
Options panels
~~~~~~~~~~~~~~
Some SIMSTAT commands in submenus are followed by three dots.
These dots indicate that an options panel appears when you choose
this command. These panels allow you to specify various options
used to adjust the program's operation, to customize the analysis
output, or to specify conditions to be fulfilled by an analysis.
To navigate through the options panels use the following keys:
<Tab>,<Dn> or <ENTER> move to the next field;
<Shift-Tab> or <Up> move to the previous field.
The action needed to edit the values of the various options depends
on the type of input field. Options panels can contain three
different types of input field:
Data entry fields - (numeric or alphanumeric) Data entry
fields are options where you must type a value using the keyboard.
They are used to enter a string of characters, a number, a
filename, etc.. When you are positioned on such a field, a blinking
text-cursor appears. The following table lists the keys that can be
used while editing a string field.
Key Effect
------------- -----------------------------------------------
<right arrow> Moves the cursor onto the character to the
right.
<left arrow> Moves the cursor onto the character to the
left.
<Ctrl-left> Moves the cursor to the beginning of the next
word.
<Ctrl-right> Moves the cursor to the beginning of the
previous word.
<Del> Deletes the character on which the cursor is
positioned.
<Backspace> Deletes the character to the left of the
cursor.
<Home> Moves the cursor to the first character of the
line.
<End> Moves the cursor to the last character of the
line.
<Ctrl-K> Delete from cursor postion to the end of the
line.
<Ins> Pressing this key toggles between insert and
overwrite mode. In insert mode, characters
are inserted at the cursor position pushing
existing text to the right of the cursor even
further right. When in overwrite mode,
characters at the cursor position are
overwritten. A blinking box cursor is used to
indicate that the insert mode is active, while
the overwrite mode is identify by a single
line cursor.
<Esc> Aborts the editing process and restore the
previous value.
Boolean fields - This type of field can take only two values
(e.g., Yes vs. No, One-tail vs. Two-tailed, etc.). When editing a
boolean field, no cursor appears. Use the <spacebar> to toggle
between the current and alternate values. You can also press the
first letter of the boolean value (e.g., Y for Yes, or N for No) to
choose it. Using this method immediately moves you to the next
field.
List fields - This type of field can take more than two
values. They can be recognized by the symbol on the right side
of the field when highlighted. By pressing the <left arrow> key, a
list box appears. You can then use the <Up> and <Dn> arrows to
highlight the proper choice and then press <Enter> to confirm it.
After the values have been edited to suit your needs, you have to
press the <F10> key to accept those values and proceed. If you
want to leave the options panel, restore the previous values, and
suspend the current operation, just press the <Esc> key.
Using the mouse
~~~~~~~~~~~~~~~
The mouse can also be used to navigate through the menus; select
and edit options; and activate some function keys. Only the left
button is used by SIMSTAT. Here are some guidelines on the way to
use the mouse.
Menus
~~~~~
- To open a menu, point to the menu name and click the left
button.
- To select a submenu command, point to the option and
click once.
- To close a submenu, position the pointer outside the menu
you want to close and click the left button.
Options panels
~~~~~~~~~~~~~~
- To select a specific field in an options panel, position
the mouse cursor on the field and click once.
- To change the value of a boolean field, position the
mouse cursor on the field and click once. If you are
currently on another field, double-clicking on the
boolean fields will achieve the same result: The first
click will position the cursor on the boolean field while
the second click will toggle its value.
- To select a value in a list field, select the list field
by clicking on it once, click again on it to bring up the
list window, position the pointer on the value you want
to choose, and click on it to confirm your choices.
- To escape from the options panel and restore the previous
values, click outside the panel.
- To accept the current values and continue, click anywhere
on the F10-to proceed expression.
Function keys
~~~~~~~~~~~~~
Most function keys appearing on the status panel or on
the border of windows can be activated with the mouse by simply
clicking anywhere on the command expression.
Getting help
~~~~~~~~~~~
No matter where you are in SIMSTAT, you can get more information
about the task you're working on by pressing <F1>. This function
key accesses SIMSTAT's context-sensitive help. When more that one
page of information is available on your current task, a PgDn or
PgUp message will appear at the bottom of the help window to tell
you that there are other pages of information. Use the
corresponding key to display those other pages. Pressing <F1>
another time accesses more general help. Press <ESC> to leave HELP
and return to your previous location.
Tutorial - Performing statistical analysis
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following section provides step-by-step instructions for
computing descriptive statistics and regression analysis on a
sample data file. The data is from an imaginary study about
various factors influencing children's aggressive behavior during
school recreational activities. This tutorial uses data stored in
the dBase III file named SAMPLE.DBF that come with your program
disk.
Step 1 - Opening a data file for analysis
The first step to performing a statistical analysis is to open a
data file that you want to analyse.
After calling up SIMSTAT, select the OPEN FILE command from the
FILE menu. This command pulls down a window that lists all valid
files and subdirectories (see Figure 2). Using the arrow keys,
position the highlighted bar on the SAMPLE.DBF (dBase) file then
press <Enter>. This opens the highlighted file. If the file is
not in the default directory, you can navigate through directories
by highlighting a subdirectory and pressing <Enter> to change to
that directory. To open a data file on a different drive, press
<F3> and select the appropriate drive letter.
If you want to perform the same operation using the mouse,
click with the left button on the FILE menu, then click on the OPEN
FILE submenu. To open the SAMPLE.DBF file, position the mouse
pointer on the file name and click twice with the left button. If
the file is not in the default directory, you can navigate through
directories by pointing to a subdirectory and double-clicking with
the left button to change to that directory.
When a file is successfully opened, its name appears at the right
end of the status panel at the bottom of the screen. The output
screen also gives information about the active file, including its
type, the number of variables and the number of cases.
Step 2 - Assigning variables
The next step is to choose the variable(s) on which you will
perform the analysis. Select the CHOOSE X-Y command from the
VARIABLE menu. The program now displays, in a window, the list of
all variables in the active file (see Figure 3). The first variable
is highlighted. Below the variable list, an information window
gives more detailed information about the highlighted variable.
Use the direction keys to move around the list and press either the
X, Y, or Z key to specify whether the variable is to be treated as
an independent variable, as a dependent variable, or as both. For
our example, highlight the AGE variable (age of the child) and
press X to select it as an independent variable. Notice that a
small x appears next to the variable name in the variable list. If
you select the wrong variable, simply move back to that variable
and press either the <DEL> key or the <SPACEBAR> to unselect it.
Next, move to the variable name HOURSTV (number of hours spent
watching TV programs with violent content) using the arrow keys,
and press X to select this variable as another independent
variable. Using the Y key, select AGRESS (number of agressive
behaviors observed) as a dependent variable.
To select a variable with the mouse, click on the variable you
want to choose, then move the mouse pointer to the status panel.
Position the mouse pointer over the definition you want to choose
and click once with the left button.
To activate the selection of variables and go back to the main
menu, press <F10>. If you want to cancel the operation and restore
the previous variable's definition, just press <Esc>.
Step 3 - Performing frequencies analysis
All the commands for statistical analyses are grouped in the four
right-most menus. We will now perform a frequency analysis on the
variables we have chosen. Select FREQUENCIES from the DESCRIBE
menu. An options panel appears on the screen. Using this panel,
we will instruct the program to print a barchart, descriptive
statistics, and a frequency table sorted by value. When the
options panel is opened, the TABLE option is highlighted. This
option is a boolean value that takes only two values: Yes or No.
You can toggle this value by pressing the space bar. You can also
type Y for yes and automatically move to the next field.
Using the proper keys, set the different options to the following
values:
Sort by: Value
Descriptive: Yes
Percentiles: No
Percentage: 90
Bar chart: Text
Pie chart: No
Pareto: No
Box-&-whiskers: Text
Cumul. chart: No
Histogram: Text
After selecting the options needed, you have to activate them and
tell SIMSTAT to perform the analysis by pressing the <F10> key, or
by clicking on the <F10> TO PROCEED statement at the lower-right
corner of the panel. SIMSTAT will calculate the necessary
statistics and display the output on your screen.
Step 4 - Viewing the results
As the results are displayed on screen, the first portion of it may
scroll out of sight at the top of the screen so that only the last
portion of the results remain visible. To browse through the
entire results press the <F2> key. This command give you access to
the BROWSE mode. To scroll backward through your results file,
press the <PgUp> key. Use the <PgDn> key to move forward through
the listing. The <Home> and the <End> keys can also be used to
move to the beginning and to the end of the file. For finer
movements, use the <Up> and <Dn> key. You can also scroll
horizontally by using the <left arrow> and <right arrow> keys.
Press <Esc> to leave the BROWSE mode and return to the main
program.
Step 5 - Selecting a subset of cases
For our second analysis, we will perform a regression analysis
using the previously selected variables. However, we will restrict
the analysis to the male subjects.
To select this subgroup, choose the SELECTION command from the
VARIABLES menu. This command displays a status panel that includes
two fields. The highlighted field allows you to specify a
condition that must be met in order to include the case in the
analysis. The sex of the child has been stored in a numeric
variable named SEX using 1 to designate boys and 2 for girls. To
select the boys for the next analysis, type the following
condition:
SEX = 1
Then press <enter> to go to the next field.
In order for the program to apply the specified selection, the
ACTIVATE SELECTION option needs to be set to Yes. If this field's
value is set to No, SIMSTAT will hold the condition in memory
without using it. Press <F10> to proceed.
Step 6 - Performing regression analysis
Choose the REGRESSION command from the COMPARE menu. An options
panel appears and the first option, TYPE, is highlighted. Note the
symbol at the right end of this option. This arrow indicates
that a list of choices is available. To examine the choices
available under this field, press the <right arrow> key on the
keyboard. SIMSTAT offers eight different types of regression. For
this example, select LINEAR by highlighting this choice and
pressing <Enter>. The cursor is now positioned on the DIRECTION
option that allows you to specify whether the significance test
should be 1 or 2-tailed. Select a 2-tailed test. To obtain a
scatterplot that will allow you to visualize the relation between
the dependent and independent variables, set the SCATTERPLOT option
to Text (for a scatterplot in ASCII characters) or Graphic (for an
high resolution graphic). At the CONF. INTERVAL option, edit the
numeric field to 90 to obtain a 90% confidence interval on beta
weights. Set the RESIDUAL PLOT to No and the STANDARDIZE RESIDUAL
to None.
When you press <F10>, SIMSTAT will calculate two separate linear
regression equations with AGRESS as the dependent variable and AGE
and HOURSTV as predictors. You can now press the <F2> key to browse
through the results.
Creating a hard-copy of analysis results
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
By default, analysis results are not preserved. Once you're out of
the program, they cannot be seen, edited or used. SIMSTAT provides
two different means for generating hard copy output of analysis
results for later use. They could be saved on disk or sent to the
printer. This section introduces you to the operations necessary
to producing a hard copy on disk and on the printer.
Saving the results on disk
The last analysis results you obtained are normally sent to a
temporarily file. This file is automatically erased when you exit
the program. If you want to keep the results in a text file, you
have to tell SIMSTAT to save those results in a listing file. One
way to do this is to choose the I/O OPTIONS command from the FILE
menu and to set the ON DISK option to YES. By default SIMSTAT
saves the listing in a file called SIMSTAT.LIS. You can change the
default filename used by the program by editing the value under the
FILENAME field. You can also toggle the disk-capture ON and OFF at
any time by pressing the <F6> key. If the disk-capture is ON, the
following result will be appended to the listing file. If the
disk-capture is OFF, they won't. In order to inform you of the
state of disk-capture, the status line will show the word disk when
the disk log is ON.
Sending the results to the printer
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Before using the print command, be sure that a printer is connected
to the computer, turned on, and supplied with paper. Also, make
sure that the program is properly configured to work with your
printer. The program's initial setting allows printing on an IBM
compatible dot-matrix printer connected to the LPT1 printer port.
(refer to the I/O OPTIONS command at page 35 to adjust the printer
setup). If you want your results sent to the printer, one way to
do it is to indicate it in the I/O OPTIONS command of the FILE
menu. However, doing this does not print results already on the
screen. You can also toggle the printer ON and OFF at any time by
pressing the <F7> key. The status line will keep you informed of
the printer status by displaying the word Printer on the status
panel when the printer log is ON.