ECOLOGICAL VALIDITY Flashcards
HISTORICAL ROOTS
Hermann von Ebbinghaus (1850-1909)
aim: general laws of memory
method: 2,300 nonsense syllables, methods of saving
finding: forgetting curve
the first 20 mins minutes had the fastest drop in retention
-A logarithmic relationship between time & forgetting
- A rapid forgetting initially, less additional forgetting at longer
delays
was scientific which made it popular
NEISSER
CRITICISMS (Neisser)
1. No new discoveries established, not advanced/trivial
2. Lack of ecological validity
3. “If X is an interesting or socially significant aspect of
memory, then psychologists have hardly ever
studied X.
10 yrs later: COUNTER ATTACK OF NEISSER’S (Banaji & crowder)
1. no theories that have unprecedented
2. explanatory power has been produced
3. no new principles of memory has been discovered
4.no methods of data collection have been developed that add
sophistication or precision”
PROBLEMS WITH THE DEFINITION OF ECOLOGICAL VALIDITY
- the importance of realistic materials and tasks
- generalisability of results
- applicability of results
CONCEPTS
TWO ASPECTS OF EV:
*GENERALISABILITY: findings reflect what’s happening in the real world
*REPRESENTATIVENESS: stimulus and tasks are similar to task and materials encountered in daily life
Generalisability + responsiveness= ecologically valid
Generalisability + non-responsive= ecologically valid
non- Generalisable + responsiveness= low EV
non- Generalisable + non-responsiveness= not ecologically valid
EXAMPLES OF STUDIES WITH GENERALISABILITY BUT NO RESPONSIVENESS
Ebbinghaus (1913)
– Forgetting Curve (Logarithmic or power function)
– A rapid forgetting initially, less additional forgetting at longer delays
Bahrick et al. (1975)
– Tested 400 high school graduates on their ability to recognize and
name classmates after delays of up to 30 years
• Similar forgetting curve for the ability to recall names from a person’s picture
Bahrick & Phelps (1984)
– Knowledge of Spanish Vocabulary over 50 year period
Meeter, Murre & Jannsen (2005)
- Tested 14,000 participants assessing recall and recognition of 1000 public events (TV news, broadcasts)
EXAMPLES OF STUDIES WITH RESPONSIVENESS BUT NO GENERALISABILITY
Early field experiments on Prospective Memory: Subjects were asked to remember to carry out simple tasks at pre-arranged times/dates. (Meacham & Leiman, 1982; see Harris, 1984).
Internal validity in question: no control of possible confounds, e.g. external mnemonic aids, low motivation
So, although the task is representative, ecological validity could be questioned.
QUESTIONS
- Which is more important for ecological validity:
Generalisability or representativeness? - Is there any difference in the concept of
generalisability within the concepts of
external validity and ecological validity?
CONT.
Jost (1897)
– Superiority of distributed practice over massed practice, i.e., The spacing effect
– Recall of nonsense syllables better where 24 repetitions over 12 days than 24 reps over 3 days
Rea & Modigliani (1985)
– Spelling lists and multiplication facts
Smith & Rothkopf (1984)
– Statistics lectures
In retrospect, Ebbinghaus and Jost’s studies appear to be no less ecologically valid than subsequent studies conducted on highly representative materials and/or settings
CONCLUSION
In retrospect, Ebbinghaus and Jost’s studies appear to be no less ecologically valid than subsequent studies conducted on highly representative materials and/or settings
Growing evidence to show that results from laboratory studies can generalize to everyday contexts and materials/tasks.
Review of this evidence in Anderson et al. (1999) and more recently in Mitchell (2012)
Ihlebak et al. (2003) – tested directly Ecological Validity of laboratory research on Eyewitness Testimony
RESULTS: Performance levels better in Video Condition
(e.g., number of details recalled, age, height, clothes)
METHOD: Memory questionnaire after the robbery or
watching the video of robbery
DV: duration of crime
characteristics of robbers (age, height, clothes, etc) and weapons used
HOWEVER, patterns of errors similar across
conditions (time estimation, correct identification of weapons)
McVay, Kane & Kwapil (2009)Psychonomic
A study of mind-wandering (daydreaming) in laboratory and everyday life
RESULTS
1. Positive relationship between mind-wandering in the
lab and everyday life
2. In both contexts mind-wandering was linked to
reduced performance on ongoing activity
role of confounding variable
Role of confounding variables?
Parrot & Sabini (1990) – Effects of mood on AMs
Journal of Personality & Soc. Psychol. 59, 321-336.
-,Found mood incongruency effect on Autob. Memories
- Happier memory was recalled on a rainy day than on
a sunny day
Contradicts mood congruency obtained in the lab studies using various mood induction
techniques
