Carl Hovland and persuasion research
Background
1929 - Rockefeller funds "Institute of Human Relations" at Yale
1936 - Hovland gets PhD at Yale, joins faculty
1941 - US joins "WWII"
1942 - Hovland takes leave to study Army morale
1942 - Frank Capra recruited to make films
when he sees Laz, Capra says "he could make 10 times that [as an actor]"
"Why We Fight" series (15 million soldiers)
Twelve 50-minute documentaries
Method
Experiments (pre/post)
200,000 soldiers
Experimental designs
Advantages:
complete control over other factors -- random assignment
temporal ordering -- experimenter "tweeks" just one thing
(Can still examine multiple factors simultaneously, though)
but must be built into the design
Example: 2 by 2 design
findings (more than 50 experiments)
"Main effects"
Big effects: soldiers learned information
Moderate effects: soldiers attitudes changed about the enemy
Small effects: soldiers were no more eager to die for their country
"Interactions"
soldiers who were smarter:
learned more
analyzed the ideas more thoroughly
were more persuade by "two sided"
with soldiers who initially agreed, one-sided was more persuasive
but with soldiers who initially disagreed, two-sided
was more persuasive
Conclusions:
media can teach factual material,
but different people have different reactions
so the effects depend on other factors
including:
the audience member's intelligence
their previous beliefs...
Publication -
day after VEday - data were "moved"
resulted in 4 books
Return to Mass Media effects syllabus
On to lecture #8