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# coefficient for reading of B = .19 (p <.001) is less than half the size of the 3^{rd }quartile

coefficient for reading in the original study, B = .49 (p < .001). For the combined

math/reading variable the coefficient of B = .38 (p < .001) in the new study is

approximately one-third the size of the standardized coefficient for the combined

math/reading variable in the original study, B = 1.07 (p < .001). Dropping to the 2^{nd }SES

quartile yields a standardized coefficient for reading scores of B = .11 (p < .001) in the

new study compared with a coefficient of B = .28 (p < .001) in the original study.

# While none of the standardized regression coefficients in this model are particularly

strong, it is worth noting that standardized regression coefficients are reduced by half for

each progressively lower SES quartile, relative to the reference group. There is a near

linear trend for SES on math achievement. Unstandardized coefficients for the 1^{st }wave

follow-up math score are b = 4.41, (p < .001) for the 2^{nd }quartile, b = 7.53 (p < .001) for

the 3^{rd }quartile, and b = 12.42 (p < .001) for the 4^{th }quartile. For those in the 4^{th }quartile,

each one point increase on the SES scale is associated with an increase of 12.42 points on

the 1^{st }wave follow-up math score, after controlling for all other independent variables in

the regression model.

# Parental Involvement

With standardized regression coefficients that are very similar to the original study,

parental checking-up on their students’ academic activities yields statistically significant,

negative effects. For the parental checking-up variable, standardized coefficients include

# B = -.05 (p < .001) for the math score; B = -.04 (p < .001) for the combined math/reading

score; and B = -.03 (p < .001) for the reading score.