Stephen Krashen
Published in: iLeader: Journal
of School Library Association of New South Wales 1(4): 3-6 (2012)
Poverty is by
far the most powerful predictor we have of school performance. This has been
established in study after study over several decades. One of the best studies showing the impact of
poverty comes from Australia: Perry and McConnery (2010) reported that both
individual levels of poverty (socio-economic status, or SES) and the poverty
level of the school have strong effects on performance, and the combination of
the two is overwhelming. Table one
presents the impact of both of these factors on performance on the PISA 2003
test of reading comprehension given to 15 year olds (math and science tests
show a similar pattern). Note that
students living in the worst poverty score 70 to 90 points lower than the most
privileged students, and students attending low SES schools score about 50 to 60
points lower than those in wealthier schools.
But low SES students in low SES schools score nearly 150 points lower
than high SES students in high SES schools.
Table One: Influence
of individual levels of socio-economic status and the socio-economic status of
the school
|
SCHOOL
SES
|
|
|
|
|
INDIVIDUAL
SES
|
1st
(lowest)
|
2nd
|
3rd
|
4th
|
5th
|
1st
(lowest)
|
459
(n=984)
|
466
(n=690)
|
472
(n=490)
|
503
(n=231)
|
516
(n=88)
|
2nd
|
486
(n=591)
|
496
(n=681)
|
503
(n=596)
|
531
(n=425)
|
544
(n=195)
|
3rd
|
498
(n=416)
|
504
(n=492)
|
515
(n=639)
|
542
(n=568)
|
561(n=348)
|
4th
|
520
(n=213)
|
525(n=377)
|
530
(n=516)
|
557
(n=682)
|
577
(n=693)
|
5th
|
548
(n=99)
|
543
(n=199)
|
549
(n=362)
|
576
(n=602)
|
602
(n=1212)
|
SES
= social economic status, based on parental occupational status, parental
education, economic and cultural resources in the home.
The
average PISA score is 500, standard deviation = 100.
From:
Perry and McConnery (2010)
SES includes a
number of factors that influence school performance. On the individual level,
students living in poverty have inferior diets and health care (Coles,
2008/2009; Berliner, 2009; Rothstein, 2010) and low SES schools lack the
facilities high SES schools do, and tend to have fewer qualified teachers. Both individual students and schools from low
SES backgrounds, however, suffer from a lack of access to books. Students from low SES families have fewer
books in the home and live in neighborhoods with inferior public libraries and
fewer bookstores, and SES schools have inferior classroom and school libraries
(Krashen, 2004).
The one source
of books that can be easily improved is the school library. In recent years two
studies have confirmed that investing in the school library can not only make a
difference, it can actually offset the impact of poverty on reading
achievement.
The California Study
Achterman’s
analysis (Achterman 2008) is based on scores on the California Standards Tests
given in 2006-2007 provided by the State of California, the California
Department of Education Library Survey, and other data provided by California
schools. Achterman used three predictors
of academic achievement: (1) “library quality,” a combination of hours the
school library is open, collection size, budget, total staff hours, total
services, and total technology, (2) a “community factor,” a combination of
parent education, the percentage of students eligible free and reduced lunch,
student ethnicity, and the percentage of English learners, and (3) a “school
factor,” the average teacher salary, which correlated with the percentage of
teachers who hold teaching credentials.
Table two presents
the results of a multiple regression analysis, a very useful statistical
procedure that allows researchers to examine the impact of individual
predictors holding other predictors constant. For example, it is likely that
community factors and library factors are related: Schools in wealthier
communities might spend more on libraries, especially in the US where local
taxes are used to pay for schools. Multiple regression allows us to pretend
that this isn’t so, that each factor is independent of the others.
The numbers in
table two are “betas.” A larger beta means a greater impact, and betas from
different predictors can be compared with each other. Table two tells us that for high school
students in California, the impact of “community” was strong on tests of both
language arts and history (beta = -.51 for language arts), consistent with the
results of studies that show the impact of poverty on school achievement. The
impact of school was positive but weak. Of great interest to us is the finding
that the effect of school library quality was strong on both tests and nearly
as strong as the effect of community, or poverty. This suggests that a strong
school library can make up for the effect of poverty in several aspects of
school achievement.
Table 2: Multiple
regression analysis: Impact of community, school, and library quality on
achievement, grade 11
|
Language Arts
|
US History
|
Community
|
-0.51
|
-0.47
|
School
|
0.14
|
0.16
|
Library
|
0.46
|
0.48
|
r2 = .57 (Language
Arts), r2 = .58 (US History)
From: Achterman (2008)
Table two
indicates that r2 = .57 for Language Arts and .46 for History. This means that
if we know the poverty level of a school (the community factor), the quality of
the teaching staff (as reflected by salaries or credentialing), and the quality
of the school library, we have 57% of the information we need to predict
Language Arts test scores for 11th graders at that school.
Confirming the
effect of the library, Achterman reported clearly positive correlations between
the size of the collection and test scores (for English language arts, r = .44)
and between the number of hours the library was open and test scores (for
English language arts, r = .52).
It must be
noted that Achterman did not find similar results for grades 4 and 8: The
effect of the library was much weaker than in grade 11. The weaker correlations
found for younger students could be due to the lack of library services in
lower grades in California, which results is limited variability and therefore
lower correlations. Achterman noted that only 1.2% of California elementary
schools have a full-time clerk and full-time librarian. This improves to 8.5%
at the middle school and 30.3% at the high school level.
The PIRLS Study
The PIRLS
organization (Progress in International Reading Literacy Study) administers a
reading test to fourth graders in many countries every few years. Students are
tested in the language of the country, and all tests are of equal difficulty.
We (Krashen, Lee and McQuillan, 2012) analyzed the 2006 PIRLS results for 40
countries.
Our analysis
included countries for which complete data was available for all factors. Most
countries tested about 4000 students from about 150 schools.
Table 3
presents one of our analyses, which examined the impact of factors considered
to be related to reading achievement. As in Achterman’s study, we used multiple
regression, which allowed us to determine the impact of each predictor
uninfluenced by the other predictors.
Table 3: Multiple Regression Analysis:
predictors of achievement on the PIRLS reading test
|
Reading
|
SES
|
-.42
|
Independent Reading
|
.19
|
Library
|
.34
|
Instruction
|
-.19
|
r2 = .63
From:
Krashen, Lee and McQuillan, 2012
According to
table 3, the strongest predictor of reading achievement among ten-year olds is
SES, socio-economic class, defined here as a combination of education, life
expectancy and wealth in each country. In agreement with many other studies, we
found that lower SES meant lower performance.
“Independent
reading” in table 3 stands for the percentage of students in each country who
participated in independent reading programs in school: Students in countries
that provided time for independent reading in school every day or almost every
day tended to do better in reading (beta = .19). This result fell just short of
the usual standard for statistical significance, but the positive relationship
between independent reading and reading proficiency is consistent with the
results of in-school self- selected reading programs (Krashen, 2004).
“Library,” in
table 3, means the percentage of school libraries in each country with over 500
books. This was a strong predictor of reading achievement. As was the case in
Achterman’s study, the library predictor was nearly as strong as social class
(similar to Achterman’s community factor).
The final
predictor in table 5, instruction, means the average hours per week devoted to
reading instruction in each country. According to our analysis, the effect of
instruction was modest and negative, that is, more instruction tended to be
related to lower performance on the reading test (beta = -.19). This predictor
fell just short of statistical significance. It may be the case that a little
reading instruction is beneficial, but after a point it is ineffective and
counterproductive.
Table 5
indicates that r2 = .63: The four variables considered here account for 63% of
the variability in reading test scores. In other words, if we know the SES
level of a country, the percentage of children who do independent reading in
school, the percentage of children who have access to a library of 500 books or
more, and the amount of instruction, this is 63% of the information we need to
predict their reading score. This r2 is quite high, and is similar to the r2
reported by Achterman.
Both Achterman’s
and our results are consistent with the results of other studies showing that
access to books from other sources can make up for the effect of poverty (Evans,
Kelley, Sikora, and Treiman, 2010; Schubert and Becker, 2010).
Conclusion
A plausible
explanation for the results of these studies and others is:
Access >
FVR > Literacy
There is very
strong evidence supporting this formula: More access to books has been shown to
lead to more self-selected reading and more self-selected reading leads to
higher levels of literacy (Krashen, 2004). There is also substantial research
connecting the ends of the formula: Better libraries are related to higher levels
of literacy (Krashen, 2004; see especially studies by Keith Curry Lance and
others at http://www.lrs.org/impact.php).
Those living in
poverty have little access to books, which explains their low levels of
literacy development. I suspect that this relationship will continue until
ereaders and ebooks are far less expensive and far more available than they are
now. The library can supply this access
immediately.
References
Achterman, D.
2008. Haves, Halves, and Have-Nots: School Libraries and Student Achievement in
California. PhD dissertation, University of North Texas. http://
digital.library.unt.edu/permalink/meta-dc-9800:1
Berliner, D.
2009. Poverty and Potential:
Out-of-School Factors and School Success. Boulder and Tempe: Education and the Public
Interest Center & Education Policy Research Unit. http://epicpolicy.org/publication/poverty-and-potential
Coles, G. 2008/2009. Hunger, academic success, and the
hard bigotry of indifference. Rethinking Schools 23 (2). http://www.rethinkingschools.org/archive/23_02/hung232.shtml;
Evans, M,
Kelley, J. Sikora, J. and Treiman, D. (2010). Family scholarly culture and
educational success: Books and schooling in 27 nations. Research in Social
Stratification and Mobility, 28 (2): 171-197.
Krashen, S.,
Lee, SY., and McQuillan, J. 2012. Is the library important? Multivariate
studies at the national and international level. Journal of Language and
Literacy Education, 8(1)? 26-36.
Perry, L. B.
& McConney, A. (2010). Does the SES of the school matter? An examination of
socioeconomic status and student achievement using PISA 2003. Teachers College
Record, 112 (4).1137-1162.
Rothstein, R. (2010). How to fix our schools. Economic Policy Institute, Issue Brief #286. http://www.epi.org/publications/entry/ib286.
Schubert,
F. and Becker, R. (2010). Social inequality of reading literacy: A longitudinal
analysis with cross-sectional data of PIRLS 2001and PISA 2000 utilizing the
pair wise matching procedure. Research in Social Stratification and Mobility
29, 109-133.
And yet funding for libraries continue to be cut. Libraries are no less important in todays world as they were in the 1800s and 1900s. People need to use them more, yet we gravitate toward computers that too often leave us aimlessly clicking from one article to another (at best) or from one game to another (at close to worst).
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