N. JAKOBSSON ET AL.
mathematics skills, while girls are underconfident. The results
regarding mathematics therefore seem to be generalizable
across cultures. Mathematics is regarded as a masculine typed
task while social science is regarded as gender neutral. The
present study shows that both girls and boys are overconfident
in their social science abilities, but girls less so than boys. We
thereby conclude that gender typedness of task does matter.
This is especially true for girls, for whom the confidence bias is
reversed across tasks. That is, girls are overconfident in the
gender neutral typed task, although less so than boys, while
they are underconfident in the masculine typed task. Further-
more, we show that girls from the all-girls school are more
underconfident in their mathematics abilities than girls in the
co-ed school. This contrasts results found for competition and
risk taking (Booth & Nolen, 2012a, 2012b), where girls in sin-
gle-sex schools are more competitive and risk taking than are
girls in mixed schools. Our finding that girls from the sin-
gle-sex school are underconfident while mixed school girls are
overconfident in the masculine typed task may suggest that
single-sex environments reinforce stereotypes of gender typed-
ness. On the other hand, since girls from the single-sex school
are less confident than girls in the mixed school in both tasks, it
may be a matter of an effect on self-confidence in general.
Thus, single sex schooling seems to affect self-confidence
differently than it affects risk taking and competitive behavior.
It may, however, also be the case that the effects differ among
countries. The results may also be driven by selection into
schools based on unobserved characteristics. Both schools are
public schools (free of charge) in Santa Tecla in El Salvador.
All children come from very poor conditions and parents are
free to register their kids at either school. We may have a prob-
lem if attendance in one of the schools is correlated with confi-
dence. If so, we cannot identify the effect of being in an
all-girls school or a co-ed school. Another potential problem is
that the children in the co-ed school answered the confidence
questions the day before their tests, while the children in the
all-girls school answered the questions two weeks before the
test. If for example time inconsistency is of importance, this
may be what drives the results. Furthermore, it is interesting to
note that the differences, especially between the different
schools, are driven by differences in results rather than differ-
ences in expectations. Taken together with the result in Hoxby
(2000) that both males and females perform better in mathe-
matics in classes with more females, this may imply that sin-
-gle-sex environments affect results without affecting confi-
dence. More research, from different contexts, is definitely
warranted to shed light on these issues.
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