investigator has no clear prediction beforehand of what this relationship might
be. If the study finds that high self-e steem people help more than low self-
esteem people, the researcher might conclude that this is because people who
feel good about themselves maintain th at positive evaluation by doing good
things. The explanation sounds reasonable, but do the data support the hypothe-
sis? From a scientific standpoint, the answer is “No”because the hypothesis was
generated after the results were seen. With that sequence, there is no way the hy-
pothesis would not be supported. If the study found that low self-esteem peoplehelp more, the same researcher might conclude that this is because these people
are trying to improve their self-image by doing good things. With no possibility
that the hypothesis might not be supported, the hypothesis has not really been
tested. This is not to say researche rs should ignore findings they haven ’tp r e -
dicted. On the contrary, such findings a re often the basis for future hypotheses
and further research. But explaining ever ything after the results are in explains
nothing.
Replication
When investigators conduct a well-designed study and uncover statistically
significant results, they usually report the findings in a journal or perhaps at
a professional conference. Sometimes the findings are cited as something re-searchers know about the topic. But psychologists are becoming increasingly
cautious about relying on one research finding when drawing conclusionsabout human behavior.
There are many reasons a researcher might find a statistically significant
effect in a given study. There could be something peculiar about the peoplein the sample. There might be something special about the time the researchwas conducted —perhaps an unusual mood in the country or on campus,
caused by an important event. Or the finding could be the result of some un-known and inadvertent aspect of the particular experimental procedure.Whatever the reason, it is dangerous to assume that a significant finding
from one study provides reliable evidence of an effect.
The way to deal with this problem is through replication. The more often
an effect is found in research, the more confidence we have that it reflects a
genuine relationship. Replications often examine participant populations dif-
ferent from those used in the original research. This helps to determine
whether the effect applies to a larger number of people or is limited to the
kind of individuals used in the original sample. Yet determining the strength
of an effect by how often it is replicated is not always easy. One difficulty
has been called the “File Drawer ”problem (Rosenthal, 1979). That is, inves-
tigators tend to publish and report research only when they find significant
effects. When an attempt at replication fails, the researcher may decide some-
thing has gone wrong —perhaps the wrong materials were used, perhaps
something was not done the way the original researcher did it, and so on.
And so the research is stored away in a file drawer and never reported. The
result is that a well-known research finding may, in fact, be difficult to repli-
cate. But because the failures at replication are stored away in file drawers,
we might not realize the problem exists.The Hypothesis-Testing Approach 27