CH.7 True Experiments II
Substantive Theme: Social and Emotional Influences on Thinking and Perceiving
- Factorial designs: an experimental design in which all conditions of the independent
variable are combined with all conditions of the other independent variable. The
main effects of each independent variable a well as the interaction effects btwn and
among the independent variables can be statistically tested
- Multifactorial- experiments that vary two or more independent variables and provides
direct tests of the main effects of each independent variable as well as the interaction
effects btwn and among the independent variables. Factorial experiments can vary the
independent variables btwn subjects, others can vary them within subjects and still
others can combine btwn subjects and within subjects manipulation of the independent
- In a multifactorial experiment, an altogether new independent variable is devised and
incorporated in to the rsrch design. Single factor experiment you just add a level but in a
multifactorial experiment you devise a new and distinct independent variable together.
Ex: idea behind the study is an interesting one of hoe emotion (mood induction) might
influence thinking (cognitive exercises) and whether a particular mood state might be
better for performing a particular cognitive exercise.
- There are many advantages to a multifactorial rsrch design. More complex than a single
factor experiment, a multifactorial design provides a more realistic model of rich psych
- Independent variables relationships can be shown, they interact; the influence of the
independent variable of mood induction differed depending upon the level of the 2 nd
Notations and Terms
- The simplest multifactorial experimental design contains 2 independent variables, each
with 2 levels or values. Factorial experiments are typically designated or identified by a
numbering notation. Ex: 2X2 factorial design has 2 ind variables, with 2 levels or values.
The number or numbers tells hw many factors or ind variables there are the number
values tell how many levels o the ind variables. A 3X4, indicates 2 indp variables, one
with 3 lrvels and the other with 4 levels.
- The order of the numbers mkes no difference. 3X4 means there are total of 12 levels of
Theory and Experimentation
- Theories of embodied cognition can be used as a conceptual model for us to understand
how we experience, perceive, and communicate emotional information - Eye gaze direction and facial expressions are 2 features that are important in conveying
- These 2 features can be an approach-avoidance motivation. Ex: Adams and Kleck cited
evidence tht has long linked anger and direct eye gaze with approach motivation. Fear
and averted gaze, they emphasized its associated with avoidance motivation. Also
further showed amygdala is known to be responsive to threat and angry facial displays
of emotion with direct or averted eye gaze.
- Adams and Kleck constructed a theory which proposes that facial expressions of
emotions and gaze direction operate as a social signaling system that governs our basic
evolved behavioural tendencies for approach or avoidance.
Decoding Facial Expressions of Emotions
- Adams and Kleck investigated 2 aspects of the face tht they thought would be
particularly important for emtnl expressions. These were facial muscle contractions tht
form diff emtnl expressions such as anger or fear and gaze direction such as direct or
averted eyes. Their challagne was to devise a way to separate these 2 conditions to study
- A and K formulated a 2 prong hypothesis: a) anger faces with direct gaze would be more
readily perceived than anger faces with averted gaze and b) fear faces with averted gaze
would be more readily perceived than fear faces with direct gaze. To test thir
hypothesis, rsrchrs had to create experimental stimuli to construct facial stimuli that
varied in expression and gaze direction
- During the experimental task, all subjects received all the treatments (within subjects
design). Advantage is that individual differences tht could figure very prominently in
processing emotions are automatically controlled, individual differences are held
constant. The second advantage is tht within subject designs are more economical than
btwn subject designs as fewer participants are needed to perform the experimental task.
- Main effect is the effects of each independent variable on a dependent variable
- A main effect can be calculated for each independent variable
- Gaze direction and emotional expression example: gaze direction didn’t influence
response rates to the facial expressions regardless of their emotional expression, faces
with direct gaze were labeled as quickly as aces with averted face. However, main effect
of emotional expression did influence response rates regardless of their gaze direction,
anger faces were correctly labeled more quickly than were fear faces.
- Interaction between the 2 ind. Variables. A statistical interaction occurs when the
effects on one level of the independent variable depend on the particular level of the other independent variable. From the example the effect of emotional expression
depended on gaze direction of the face.
Interpreting results of multifactorial designs
- This design provides 2 distinct sources of info: 1. Main effect of each independent
variable by itself 2. Interaction effect of th