Change in average science scores of 4th-grade students, by education system: 2007�2011 and 1995�2011
Score is higher than U.S. score.
Score is lower than U.S. score.
Change from 2007 to 2011.
Change from 1995 to 2011.
# Rounds to zero.
*p<.05. Change in average scores is significant. 1 The change in average score is calculated by subtracting the 2007 or
1995 estimate, respectively, from the 2011 estimate using unrounded numbers. 2 National Defined Population covers 90 to 95 percent of National Target
Population for 2011 (see appendix A). 3 Met guidelines for sample participation rates only after replacement
schools were included for 2011. 4 National Target Population does not include all of the International
Target Population for 2011 (see appendix A). 5 Nearly satisfied guidelines for sample participation rates after replacement
schools were included for 2011. 6 Exclusion rates for Georgia are slightly underestimated
as some conflict zones were not covered and no official statistics were available
for 2011. 7 The TIMSS International Study Center has reservations about the reliability
of the average achievement score because the percentage of students with
achievement too low for estimation in 2011 exceeds 15 percent, though it is less
than 25 percent.
NOTE: Education systems are ordered by 2011 average scores. Italics indicate participants
identified and counted in this report as an education system and not as a separate
country. All education systems met international sampling and other guidelines in
2011, except as noted. Data are not shown for some education systems because comparable
data from previous cycles are not available. Participants that did not administer
TIMSS at the target grade are not shown; see the international report for their
results. All U.S. state data are based on public school students only.
For 1995, Korea, Portugal, and Ontario-CAN had National Defined Population covering
90 to 95 percent of National Target Population; England-GBR had National Defined
Population that covered less than 90 percent of National Target Population (but
at least 77 percent); England-GBR, Netherlands, Australia, and Austria did not satisfy
guidelines for sample participation rates. For 2007, the United States, Quebec-CAN,
Ontario-CAN, and Alberta-CAN had National Defined Population covering 90 to 95 percent
of National Target Population; the United States and Denmark met guidelines for
sample participation rates only after replacement schools were included; the Netherlands
and Dubai-UAE nearly satisfied guidelines for sample participation rates after replacement
schools were included; Georgia had a National Target Population that did not include
all of the International Target Population; Dubai-UAE tested the same cohort of
students as other countries, but later in the assessment year at the beginning of
the next school year.
All average scores reported as higher or lower than the U.S. average score are different
at the .05 level of statistical significance. The tests for significance take into
account the standard error for the reported difference. Thus, a small difference
between averages for one education system may be significant, while a large difference
for another education system may not be significant. Detail may not sum to totals
because of rounding. The standard errors of the estimates are shown in table E-24
available at http://nces.ed.gov/pubsearch/pubsinfo.asp?pubid=2013009.
SOURCE: International Association for the Evaluation of Educational Achievement
(IEA), Trends in International Mathematics and Science Study (TIMSS), 1995, 2007,