User`s guide

E-Prime User’s Guide
Chapter 1: Introduction
Page 9
Because the two products are fundamentally different, it is strongly recommended that even the
most experienced PsyScope user work through the Getting Started Guide as an introduction to E-
Prime. PsyScope users who have spent a few hours working with Windows programs will quickly
realize that many aspects of the E-Prime interface are simply echoes of Windows metaphors.
This is particularly true for the system of window control, and navigation in E-Studio and the
Structure view. We designed these components using metaphors from Windows utilities such as
Windows Explorer, which are familiar to Windows users. For the Mac user, who is unfamiliar with
Windows, some of these approaches, such as manipulation of the Structure view, will seem
unnatural and clumsy. However, after a bit of exploration, they become easy to use.
The biggest improvement that E-Prime makes over PsyScope is in the way that it avoids deep
embedding of actions in the user interface. In PsyScope, it was often necessary to click down
three or four levels to link objects between the Factor Table and a stimulus list. In addition, the
properties of levels of the design as realized in the Factor Table were only accessible by going
through the template for each cell and then down to the individual lists. In E-Prime, the various
views allow greater access to properties (e.g., Workspace, Properties window, Attributes viewer),
and the highlighting of attribute references through color-coding visually indicates to the user
which properties are varying.
E-Prime’s second major advance over PsyScope, which we discussed earlier, is the fact that
users can embed blocks of E-Basic code virtually at will directly within the visual environment. In
PsyScope, one had to choose between using the graphic environment or using PsyScript. In E-
Prime, one can have scriptability within the graphic environment using E-Basic. E-Basic is an
object-based language that encapsulates both data and the methods used to manipulate that
data into units called objects. E-Basic is almost identical to Visual Basic for Applications, with
additional commands used to address the needs of empirical research. E-Basic is extensible to
allow an experienced programmer to write Windows DLLs to expand E-Prime’s functionality with
C/C++ code.
The third major advance in E-Prime is its stability. As users are well aware, PsyScope was prone
to bugs and crashes. Many of these problems were caused by complex interactions between the
windowing environment and the operating system. Typically, users would build up complex
designs in a factor table and then not be able to consistently apply local changes to particular
levels. Eventually, PsyScope would lose track of objects and the whole experiment would crash.
E-Prime has conquered these problems. However, one casualty of this clean-up has been
elimination of the flexible system of PsyScope windows, including the modal windows, the
expandable Factor Table, dynamic script updating, and the “ports” dialog for building screen
displays. These same facilities are available in E-Prime, but they are less dynamic. For
example, while the PsyScope script was active and displayed modifications immediately, E-Prime
is more of a graphical user interface, and requires the user to regenerate the script in order for
changes to be viewed. At the same time, the overall interface is much more stable and less
prone to crashing.
The fourth major advance in E-Prime is its significantly improved system of display and response
time measurement. Although timing was accurate in PsyScope, few tools were provided to the
user that would allow them to verify timing. E-Prime provides these tools along with careful
documentation on how to maximize precision and test for accuracy. Many of these tools are
automated. For example, one can turn on time audit variables in logging and the accuracy of
presentation will be continually recorded and stored in the data output file.
The fifth major advance in E-Prime is its tighter linkage to data output. In PsyScope, researchers
could use PsyDat, PsySquash, or their own scripts to control the movement of data to statistical
programs. E-Prime handles data movement and processing through the E-Merge and E-DataAid