Experimenter Expectancy Effect On Children in a Classroom Setting


	Rosenthal and Jacobson (1966) sought to test the experimenter expectancy effect by 
examining how much of an outcome teachers' expectancies could have on a group of children.  
Earlier investigations in this area were also conducted by Rosenthal (1963).  He worked with 
children in a research lab, giving each one a rat and telling them it was either bred for 
intelligence or for dullness.  The children were put in charge of teaching the rats how to learn 
mazes.  Rosenthal's results showed that the rats that were believed by the students to be smart, 
were able to learn the mazes much quicker.  What the children did not know, i.e., what 
Rosenthal had kept hidden, was that the rats were chosen at random.  There were no rats that
were especially bright or dull.  Another case of the experimenter expectancy effect was that of 
the horse known as "Clever Hans".  It seemed to be able to read, spell, and solve math problems 
by kicking his leg a number of times.  The horse was tested and passed, but what the experts did 
not realize was that their own hopes for the horse to answer the questions, were giving the horse 
signs on which he based his answers.  That is, if someone on the committee raised his/her 
eyebrows in anticipation of the oncoming correct answer, the horse would stop stomping.  Once 
again, the experimenter's cues decided the outcome of the tests.  Acting on these results,
Rosenthal and Jacobson hypothesized that teacher's expectancies would cause them 
unintentionally to treat the students they thought to be bright in a different manner than those 
they thought to be average or even less bright.  	
	Rosenthal and Jacobson used some materials that were important in the completing their 
investigation.  The experimenters used students and their teachers as the subjects of their study. 
As part of their experiment, they even chose which grades the students would be in.  They also
used Flanagan's Tests of General Ability as a disguise to predict academic expectancies.  The 
experimenters did not use anything else in their experiment but instead let their subjects do the 
rest.  Rosenthal and Jacobson's goal was to see how teachers would treat students whom they 
thought were of above average intelligence in comparison to how they treated students whom 
they believed were of below average intelligence.
	As with all experiments, there needed to be variables.  In trying to test teacher's 
expectancies, Rosenthal and Jacobson used labels for children as their independent variable.  
The labels used were "bloomers" for children who were expected to be above average, while the 
other group of children were labeled as average.  Rosenthal and Jacobson wanted to see how 
children being labeled as dull or bright would contribute to how teachers would react to them.  
The teacher's reaction tended to be in the form of giving the bright children more attention and 
expecting them to score higher grades and perform better in class.  Because the teacher's 
reaction depends on how the children were labeled, it was dependent on the first variable.  The 
teacher's reactions to the children's labels, was the experimenter's dependent variable.  
	Rosenthal and Jacobson controlled every aspect of the experiment.  They chose which 
children would be seen as dull or bright by having scores from Flanagan's Test of General 
Ability sent to the teachers.  They also chose which grades of children would be used and which 
teachers would be in the experiment.  The experimenters maintained a high degree of control, 
and they told no one else of what they were really studying.
	The children in the experimental group averaged 12.2 points of improvement in their 
intellectual growth.  The students in the control group averaged 8.2 points of intellectual growth.  
Reporting the average is not an accurate way of showing the difference in IQ point increases 
though.  The third through sixth grade reported almost no difference in the gains, but the first 
and second grades differed as much as 15 points.  The difference in scores shows the effect that 
teachers can have on their students.  Particularly in the first and second grades, the amount that 
teachers expect from their students is the amount they will receive.
	This study could be improved in a few ways.  First, the students were tested at the end of 
the school year with the same test they had been given to initially decide their IQs.  A different 
test of intelligence should be given to the students.  Being given the same test, some of the 
students may be given the same questions which is an unfair advantage to them because they will 
know the answers from the previous test.  Another way to improve the study would be by  having 
the study performed in both private and public schools and by starting it in preschool  and ending 
it at eighth grade in stead of sixth.  
	Because of this survey, a consequent study was performed by Chaiken, Sigler, and 
Derlega (1974).  They set up a camera in a classroom in which teachers had been informed  that 
some of the students were gifted while others were dull.  The recording showed that teachers 
tended to smile more at the supposedly gifted students, acted more favorably to their comments 
in class, and made more eye contact with them.  Other new research that could be performed 
would be a study to see what would happen if a teacher was told his/her entire class was either 
gifted or dull and see how they react to an entire class like that.
	I have learned a lot from this article.  Having a desire to become a teacher, this article has 
shown me just how much of a reaction my attention to students may have on them.  I would like 
to become a high school or college professor.  Even though Rosenthal and Jacobson's 
experiment revealed that the older the children, the less they were affected by the teacher's 
expectancies, I would like to see the same experiment performed on high school children.  This 
would reinforce Rosenthal and Jacobson's findings and take some pressure away from how 
teachers feel they have to react to older students.