TABLE 2.
Descriptive statistics for the numeracy skill groups at the 54-month assessment
| DCM attribute groups at the 54-month assessment |
||||
|---|---|---|---|---|
| NAP | C | CR | CRA | |
| N | 166 | 327 | 285 | 263 |
| %child race and ethnicity | ||||
| White | 0.53 (0.50) | 0.76 (0.43) | 0.87 (0.34) | 0.90 (0.30) |
| Black | 0.30 (0.46) | 0.14 (0.34) | 0.06 (0.24) | 0.01 (0.09) |
| Hispanic | 0.13 (0.33) | 0.05 (0.23) | 0.04 (0.19) | 0.04 (0.19) |
| Other | 0.04 (0.20) | 0.05 (0.21) | 0.03 (0.16) | 0.06 (0.23) |
| Mother’s education (in years) | 12.98 (2.24) | 13.87 (2.38) | 14.95 (2.26) | 15.49 (2.32) |
| Mother’s PPVT score | 86.78 (19.02) | 96.84 (15.84) | 102.88 (16.55) | 107.63 (17.26) |
| Partner in home (EC) | 0.74 (0.38) | 0.83 (0.32) | 0.89 (0.27) | 0.94 (0.19) |
| Stable income to needs (EC) | 2.23 (1.76) | 3.20 (2.35) | 3.94 (2.34) | 4.86 (3.54) |
| Average HOME score (EC) | 36.55 (5.36) | 39.93 (4.46) | 41.49 (3.59) | 42.50 (3.11) |
| Proportion Centre care (36–54 m) | 0.32 (0.36) | 0.39 (0.37) | 0.45 (0.39) | 0.46 (0.40) |
| Memory for sentences 54 m | 75.92 (14.24) | 88.02 (15.98) | 97.27 (15.60) | 101.07 (18.39) |
| Bayley MDI | 77.90 (13.45) | 89.92 (12.89) | 95.95 (12.37) | 101.69 (11.00) |
| Percentage correct | ||||
| Counting | 0.32 (0.18) | 0.79 (0.12) | 0.92 (0.08) | 0.95 (0.07) |
| Concrete representational arithmetic | 0.13 (0.16) | 0.23 (0.16) | 0.66 (0.17) | 0.70 (0.22) |
| Abstract arithmetic | 0.02 (0.07) | 0.03 (0.10) | 0.00 (0.00) | 0.48 (0.21) |
| Clocks | 0.07 (0.21) | 0.25 (0.39) | 0.55 (0.43) | 0.62 (0.43) |
| WJ-R applied problems (W score) | ||||
| 54 months | 391.84 (17.02) | 419.54 (7.25) | 434.51 (5.60) | 441.98 (8.37) |
| First grade | 454.65 (12.83) | 465.58 (13.29) | 472.80 (12.38) | 480.30 (13.01) |
| Third grade | 485.41 (16.02) | 494.82 (11.52) | 501.00 (8.59) | 504.22 (9.37) |
| Fifth grade | 499.58 (13.60) | 507.85 (10.43) | 513.69 (9.18) | 515.79 (9.66) |
| Age 15 | 512.78 (14.67) | 518.64 (13.25) | 528.68 (14.64) | 533.95 (15.96) |
| % high school highest math coursea | ||||
| Algebra 1 | 0.26 (0.45) | 0.07 (0.25) | 0.00 (0.00) | 0.01 (0.11) |
| Geometry | 0.05 (0.22) | 0.09 (0.29) | 0.04 (0.21) | 0.02 (0.13) |
| Algebra 2 | 0.33 (0.48) | 0.22 (0.42) | 0.26 (0.44) | 0.12 (0.33) |
| Advanced math | 0.31 (0.47) | 0.47 (0.50) | 0.36 (0.48) | 0.43 (0.50) |
| Calculus | 0.05 (0.22) | 0.15 (0.36) | 0.34 (0.47) | 0.42 (0.49) |
| % college enrollment | ||||
| Less than HS | 0.05 (0.23) | 0.02 (0.12) | 0.02 (0.07) | 0.01 (0.10) |
| HS graduate | 0.29 (0.46) | 0.17 (0.38) | 0.12 (0.33) | 0.11 (0.31) |
| Two-year college | 0.40 (0.49) | 0.28 (0.45) | 0.24 (0.43) | 0.12 (0.33) |
| Four-year college | 0.26 (0.44) | 0.53 (0.50) | 0.62 (0.49) | 0.76 (0.43) |
Note: Means are reported with standard deviations in parentheses.
Abbreviations: C, counting mastery; CR, counting and concrete representational arithmetic mastery; CRA, counting, concrete representational and abstract arithmetic mastery; DCM, diagnostic classification model; EC, average of the variable reported at 1-, 6-, 15-, 24-, 36- and 54-month interviews; HOME, home observation for measurement of the environment; m, months; MDI, mental developmental index; NAP, no applied problems mastery; PPVT, peabody picture vocabulary test; WJ-R, Woodcock-Johnson revised.
Due to sample attrition, the sample size for the high school’s highest math course variables was lower than that for the remaining variables. See Table 1 for a comparison of the full sample and the high school sample.