大学生市场营销诺丁汉大学E-PRIME教程

Learning to use E-prime

By the end of this tutorial you should:

-

understand lists, procedures, text displays, feedback displays and

image displays;

-

be able to randomise lists of stimuli, add new stimuli to an experiment

(text and images), specify a correct response for stimuli;

-

alter the duration of a stimulus

-

collate data and obtain means for different conditions.

Step 1. Open E-prime from Start>programs>E-prime>e-studio. You will be

presented with the start screen:

This is the tool box where

text displays, feedback

etc. can be selected.

This is the structure window.

This contains a hierarchical

description of your experiment

These are the Properties of

whatever object you have

selected in the structure

window

This is the workspace. Selecting

an object in the structure window

brings up a representation in the

workspace for you to work upon.

Step 2. You are going to design an experiment with the following instructions:

You are going to see a series of pictures and words. Each stimulus will be

preceded by a fixation cross. Please stare at the cross before the stimulus

appears. When the stimulus appears press Z if it is an animal, and M if it is

furniture.

First you should type in the instructions. Double click on Session Proc in the

structure window. This opens a procedure line in the workspace. Drag a text

display from the toolbox onto the procedure line:

Then double click on the text display icon in either the procedure line or the

structure window. This opens the text display in the workspace. Type in the

instructions.

Now we need to tell the computer to display those instructions until the

subject presses the space bar. Click on the property pages icon of the text

display. This opens the properties of the text display that you are working with:

Change the back colour to black and the

fore colour to white (or colours of your

choice).

Then click on the duration tab

The duration of the stimulus can be set to anything in ms.

In this instance we want it to be dependant on the subject

pressing a button. In these cases you should put –1 in the

duration box. If you wanted it to last for a second, you

would put 1000.

Click on the ‘add’ button to add a response. Choose

keyboard.

The default is {ANY} button, but if you wanted to be more

specific you would type {SPACE}. Normal alphanumeric

keys are entered into this box without parentheses.

Step 3: Create a list. Lists are created when you have one or more blocks of

stimuli that need to be repeated in a series of trials. This experiment has two

blocks, one using words and one using pictures. We will need three lists in

total. The first list will contain the ‘wordblock’ and the ‘imageblock’. Both of

these blocks need a list of their own that will be subordinate to the first list.

Drag a list icon from the tool box and place it on the procedure line after the

text display. Double click on the list in the procedure line to open it in the

workspace.

The list opens with only one row. Add another row

by clicking the ‘add row’ button.

In the Procedure column type ‘wordblock’ for one

row and ‘imageblock’ for the second row.

Notice that two new procedures have now appeared

in the structure window. Now double click on the first

procedure to open up the line in the workspace.

Drag your second list icon from the toolbox and

place it on this line. Double click on this second list

icon to open it up in the workspace.

Step 4: creating a subordinate procedure.

In this new list you first need to add three extra rows and two

extra columns using the buttons at the top of the window.

Each row is a trial. The ‘weight’ reflects how many times the

trial is run in that experiment. For this experiment change the

weight to 3 for each row. This results in 12 trials for this block.

Type ‘wordproc’ in the Procedure column for each row.

Name the first extra column ‘Stimulus’. This is where you tell

the computer what to present. Type Tiger, Horse, Chair and

Table in the four rows of this column.

Name the second column ‘CorrectAnswer’. The first two rows

should be Z and the last two rows should be M (small letters

–

not capitals).

Next, double click on wordproc to open the procedure line in the workspace.

Drag two text displays onto the line and one feedback display. The first text

display will be our fixation cross at the start of each trial. Double click on the

first text display and simply type a plus sign (+) in the text box. Click on the

property pages icon in the top corner of the box in the workspace and click on

the duration tab (see Step 2). Alter the duration to 500. This means that the

fixation cross will appear for half a second.

Now open the second text display in the workspace. This text display will be

used to display the stimuli. In the text box type [stimulus]. Adding the square

brackets means that e-prime will access the text from the list (i.e. it will

present ‘Tiger’, ‘Horse’, ‘Table’ or ‘Chair’ depending on what row of the list e-

prime is accessing). Click on the property pages and select duration:

a)

e)

c)

d)

b)

Now double click on the feedback display item in the structure window to open

it up in the workspace:

Ensure that the Feedbackdisplay1 is

selected.

Click on the property pages icon.

a). Change the duration to –1. The stimulus

will be presented until the subject makes a

response.

b). Add a keyboard response

c). The allowable keys that subjects can press

are Z and M. Both should be entered here.

d). In order to give the subject feedback e-

prime needs to know what the correct answer

is. Here, you can tell the computer that the

correct answer can be found in the list. Enter

[correctanswer] and e-prime will check the

appropriate column.

e). Make sure that data logging is set to

standard, otherwise e-prime will not record

whether the subject was correct or not.

In the Input Object Name slot you need to

enter the name of the object to which you

want to attach feedback (i.e. the one they

respond to). The drop down menu shows you

what’s available. If you haven’t changed the

names of any of the objects in the structure

window, then the entry should be

TextDisplay3.