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NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Assessment IRT Parameters → Geography Assessment IRT Parameters → IRT Parameters for Items in the Space and Place Subscale, Grade 8 Geography National Assessment, by Block and Item: 2018
NAEP Technical DocumentationIRT Parameters for Items in the Space and Place Subscale, Grade 8 Geography National Assessment, by Block and Item: 2018
| Block | Item | NAEP ID | aj | bj | cj | dj1 | dj2 | dj3 | dj4 | dj5 |
|---|---|---|---|---|---|---|---|---|---|---|
| G1 | 1 | G018901 | 0.83 | -0.56 | 0.14 | † | † | † | † | † |
| 2 | G019001 | 0.75 | -2.36 | 0.21 | † | † | † | † | † | |
| 4 | G0190MS | 0.36 | 0.10 | † | -6.04 | 6.04 | † | † | † | |
| 7 | G019301 | 1.22 | -0.05 | 0.14 | † | † | † | † | † | |
| 8 | G019401 | 1.21 | 0.66 | 0.17 | † | † | † | † | † | |
| 9 | G019402 | 0.55 | 0.11 | † | 0.05 | -0.05 | † | † | † | |
| 10 | G019403 | 0.46 | 0.72 | 0.25 | † | † | † | † | † | |
| 11 | G019501 | 0.62 | -0.90 | 0.18 | † | † | † | † | † | |
| 12 | G019601 | 0.64 | 0.17 | 0.25 | † | † | † | † | † | |
| 13 | G019701 | 0.56 | 0.61 | 0.23 | † | † | † | † | † | |
| 14 | G019702 | 0.51 | -0.62 | 0.20 | † | † | † | † | † | |
| 15 | G019703 | 0.88 | 0.80 | 0.28 | † | † | † | † | † | |
| 16 | G019801 | 0.71 | -0.54 | 0.21 | † | † | † | † | † | |
| 19 | G020101 | 0.71 | 0.41 | 0.24 | † | † | † | † | † | |
| G2 | 1 | G046101 | 0.68 | 1.64 | 0.26 | † | † | † | † | † |
| 2 | G046201 | 0.23 | -1.59 | 0.22 | † | † | † | † | † | |
| 3 | G049001 | 0.49 | -0.70 | † | † | † | † | † | † | |
| 8 | G049201 | 0.64 | 0.63 | 0.25 | † | † | † | † | † | |
| 9 | G048901 | 0.69 | 0.51 | 0.20 | † | † | † | † | † | |
| 13 | G050101 | 1.09 | 0.04 | 0.23 | † | † | † | † | † | |
| 14 | G050102 | 0.93 | 2.62 | 0.15 | † | † | † | † | † | |
| 17 | G048201 | 1.05 | 0.81 | 0.18 | † | † | † | † | † | |
| G3 | 1 | G013301 | 0.85 | -1.62 | 0.19 | † | † | † | † | † |
| 2 | G013302 | 0.48 | -0.95 | 0.22 | † | † | † | † | † | |
| 3 | G013401 | 0.71 | -1.48 | 0.18 | † | † | † | † | † | |
| 7 | G013601 | 0.64 | -1.46 | 0.21 | † | † | † | † | † | |
| 8 | G013602 | 0.42 | -0.19 | 0.21 | † | † | † | † | † | |
| 9 | G013701 | 0.79 | -0.66 | 0.19 | † | † | † | † | † | |
| 13 | G014101 | 0.50 | 2.22 | 0.15 | † | † | † | † | † | |
| 16 | G0144MS | 0.53 | 1.33 | † | 2.65 | -2.65 | † | † | † | |
| 17 | G014501 | 0.43 | 2.51 | 0.21 | † | † | † | † | † | |
| 20 | G020401 | 0.43 | -0.90 | 0.18 | † | † | † | † | † | |
| G4 | 4 | G033201 | 0.57 | 0.42 | 0.20 | † | † | † | † | † |
| 11 | G033901 | 0.87 | 1.34 | 0.20 | † | † | † | † | † | |
| 15 | G034301 | 0.41 | 1.09 | 0.21 | † | † | † | † | † | |
| 16 | G034401 | 0.58 | 0.35 | 0.25 | † | † | † | † | † | |
| 18 | G034501 | 0.69 | 0.36 | 0.20 | † | † | † | † | † | |
| G5 | 2 | G050001 | 0.52 | 2.01 | † | 1.39 | -0.87 | -0.52 | † | † |
| 3 | G046701 | 0.51 | -0.12 | † | 1.02 | -1.02 | † | † | † | |
| 5 | G051301 | 0.38 | 3.04 | 0.19 | † | † | † | † | † | |
| 6 | G048701 | 0.52 | 0.44 | 0.18 | † | † | † | † | † | |
| 12 | G048601 | 0.44 | 1.54 | 0.18 | † | † | † | † | † | |
| 15 | G047001 | 1.06 | 0.44 | 0.25 | † | † | † | † | † | |
| 17 | G049801 | 0.88 | -0.64 | 0.27 | † | † | † | † | † | |
| G6 | 1 | G0636MS | 0.50 | -3.22 | † | † | † | † | † | † |
| 2 | G0611MS | 0.44 | -1.67 | † | -1.50 | 1.50 | † | † | † | |
| 3 | G0672MS | 0.83 | -0.60 | † | 1.53 | -1.53 | † | † | † | |
| 6 | G061601 | 0.55 | 0.89 | 0.26 | † | † | † | † | † | |
| 9 | G064601 | 0.55 | -0.22 | 0.20 | † | † | † | † | † | |
| 10 | G063801 | 0.42 | 0.57 | 0.21 | † | † | † | † | † | |
| 11 | G0598MS | 0.55 | -1.41 | † | 1.57 | -1.57 | † | † | † | |
| 12 | G0660MS | 0.59 | 0.91 | † | † | † | † | † | † | |
| 13 | G062501 | 0.70 | -0.53 | 0.25 | † | † | † | † | † | |
| 14 | G062401 | 0.36 | -1.62 | 0.21 | † | † | † | † | † | |
| 16 | G066501 | 0.53 | 0.60 | 0.20 | † | † | † | † | † | |
| 17 | G060801 | 1.03 | 0.66 | 0.12 | † | † | † | † | † | |
| 18 | G066201 | 0.85 | 1.61 | 0.12 | † | † | † | † | † | |
| 20 | G066901 | 0.85 | -1.16 | 0.21 | † | † | † | † | † | |
| 21 | G067001 | 1.00 | -0.18 | 0.22 | † | † | † | † | † | |
| G7 | 2 | G0613MS | 0.66 | 0.03 | † | † | † | † | † | † |
| 4 | G0618MS | 0.97 | -1.38 | † | 0.25 | -0.25 | † | † | † | |
| 6 | G063201 | 0.58 | 2.04 | 0.19 | † | † | † | † | † | |
| 7 | G062001 | 0.60 | -0.07 | † | † | † | † | † | † | |
| 8 | G067501 | 0.51 | -1.09 | 0.19 | † | † | † | † | † | |
| 9 | G065101 | 0.38 | -0.84 | 0.21 | † | † | † | † | † | |
| 11 | G061501 | 0.99 | 0.14 | 0.16 | † | † | † | † | † | |
| 12 | G062701 | 0.43 | -1.92 | 0.20 | † | † | † | † | † | |
| 17 | G065501 | 0.62 | -0.65 | 0.21 | † | † | † | † | † | |
| 18 | G0603MS | 0.43 | 0.55 | † | † | † | † | † | † | |
| 19 | G068301 | 0.94 | 0.53 | 0.09 | † | † | † | † | † | |
| 22 | G064801 | 0.40 | 0.37 | 0.19 | † | † | † | † | † | |
| 23 | G0664MS | 0.93 | -1.07 | † | 1.04 | -0.16 | -0.88 | † | † | |
| † Not applicable;
c parameters are not estimated for the two-parameter logistic or generalized partial credit models, and
d parameters are not estimated for two-parameter or three-parameter logistic models. NOTE: DBA = Digitally based assessment. For item j, aj represents the discriminatory power of the item, bj represents a location parameter related to item difficulty, cj represents the guessing parameter, and dji represents the category threshold parameter for category i. The c parameter value is assumed to be exactly zero and is not estimated for items scaled with the two-parameter logistic model. For item j, dji may not sum to zero because of rounding. The block naming conventions used in this table are described in the document 2018 Block Naming Conventions in Data Products and TDW  .SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2018 Geography Assessment. | ||||||||||
| Block | Item | NAEP ID | aj | bj | cj | dj1 | dj2 | dj3 | dj4 | dj5 |
|---|---|---|---|---|---|---|---|---|---|---|
| G3 | 1 | G013301 | 0.73 | -1.60 | 0.24 | † | † | † | † | † |
| 2 | G013302 | 0.49 | -1.02 | 0.27 | † | † | † | † | † | |
| 3 | G013401 | 0.82 | -1.11 | 0.24 | † | † | † | † | † | |
| 7 | G013601 | 0.70 | -1.48 | 0.23 | † | † | † | † | † | |
| 8 | G013602 | 0.52 | -0.37 | 0.20 | † | † | † | † | † | |
| 9 | G013701 | 0.78 | -0.54 | 0.22 | † | † | † | † | † | |
| 13 | G014101 | 0.92 | 1.47 | 0.15 | † | † | † | † | † | |
| 16 | G014401 | 0.60 | 2.28 | † | 2.38 | -2.38 | † | † | † | |
| 17 | G014501 | 0.54 | 2.26 | 0.22 | † | † | † | † | † | |
| G4 | 4 | G033201 | 1.08 | 0.77 | 0.33 | † | † | † | † | † |
| 11 | G033901 | 1.33 | 1.19 | 0.24 | † | † | † | † | † | |
| 15 | G034301 | 0.72 | 0.95 | 0.28 | † | † | † | † | † | |
| 16 | G034401 | 0.79 | 0.39 | 0.38 | † | † | † | † | † | |
| G5 | 2 | G050001 | 0.43 | 1.20 | † | 0.37 | -0.37 | † | † | † |
| 3 | G046701 | 0.55 | -0.19 | † | 0.89 | -0.89 | † | † | † | |
| 5 | G051301 | 0.81 | 1.56 | 0.20 | † | † | † | † | † | |
| 6 | G048701 | 0.67 | 0.58 | 0.24 | † | † | † | † | † | |
| 12 | G048601 | 0.88 | 1.30 | 0.25 | † | † | † | † | † | |
| 15 | G047001 | 1.02 | 0.64 | 0.31 | † | † | † | † | † | |
| 17 | G049801 | 1.18 | -0.41 | 0.36 | † | † | † | † | † | |
| G6 | 1 | G034501 | 0.57 | -0.42 | 0.23 | † | † | † | † | † |
| 11 | G035501 | 0.74 | 1.86 | † | 0.70 | 0.22 | -0.92 | † | † | |
| G7 | 1 | G051801 | 0.98 | -0.28 | 0.22 | † | † | † | † | † |
| 2 | G051601 | 0.31 | -0.86 | † | -2.99 | 0.60 | 2.39 | † | † | |
| 3 | G051501 | 0.70 | -0.41 | 0.15 | † | † | † | † | † | |
| 4 | G052101 | 0.39 | -1.65 | 0.23 | † | † | † | † | † | |
| 5 | G052901 | 0.61 | -0.52 | † | 0.48 | -0.48 | † | † | † | |
| 6 | G052601 | 1.02 | -0.45 | 0.24 | † | † | † | † | † | |
| 7 | G053201 | 1.05 | 0.53 | 0.11 | † | † | † | † | † | |
| 8 | G052501 | 0.77 | 1.46 | † | -0.65 | 0.65 | † | † | † | |
| 12 | G052701 | 1.10 | 1.59 | 0.24 | † | † | † | † | † | |
| 15 | G053801 | 1.65 | 0.50 | 0.31 | † | † | † | † | † | |
| G8 | 1 | G046101 | 0.59 | 1.67 | 0.22 | † | † | † | † | † |
| 2 | G046201 | 0.36 | -1.00 | 0.23 | † | † | † | † | † | |
| 3 | G049001 | 0.53 | -0.95 | † | † | † | † | † | † | |
| 8 | G049201 | 0.91 | 0.61 | 0.35 | † | † | † | † | † | |
| 9 | G048901 | 0.76 | 0.51 | 0.23 | † | † | † | † | † | |
| 13 | G050101 | 1.02 | -0.17 | 0.17 | † | † | † | † | † | |
| 14 | G050102 | 1.03 | 2.94 | 0.17 | † | † | † | † | † | |
| 17 | G048201 | 0.99 | 0.85 | 0.20 | † | † | † | † | † | |
| G9 | 1 | G018901 | 0.87 | -0.69 | 0.20 | † | † | † | † | † |
| 2 | G019001 | 0.86 | -2.52 | 0.24 | † | † | † | † | † | |
| 3 | G019002 | 0.27 | 0.24 | † | -7.55 | 7.55 | † | † | † | |
| 9 | G019301 | 0.95 | 0.08 | 0.14 | † | † | † | † | † | |
| 10 | G019302 | 0.47 | -0.10 | † | 1.18 | -1.18 | † | † | † | |
| 11 | G019401 | 1.70 | 0.81 | 0.14 | † | † | † | † | † | |
| 12 | G019402 | 0.62 | 0.15 | † | 0.16 | -0.16 | † | † | † | |
| 13 | G019403 | 0.33 | 0.47 | 0.22 | † | † | † | † | † | |
| 14 | G019501 | 0.56 | -0.87 | 0.21 | † | † | † | † | † | |
| 15 | G019601 | 0.65 | -0.29 | 0.25 | † | † | † | † | † | |
| 16 | G019701 | 0.65 | 1.43 | 0.30 | † | † | † | † | † | |
| 17 | G019702 | 0.54 | -0.35 | 0.28 | † | † | † | † | † | |
| 18 | G019703 | 0.54 | 0.53 | 0.25 | † | † | † | † | † | |
| 19 | G019801 | 0.55 | -0.78 | 0.22 | † | † | † | † | † | |
| 22 | G020101 | 0.80 | 0.49 | 0.25 | † | † | † | † | † | |
| 26 | G020401 | 0.32 | -1.48 | 0.22 | † | † | † | † | † | |
| † Not applicable;
c parameters are not estimated for the two-parameter logistic or generalized partial credit models, and
d parameters are not estimated for two-parameter or three-parameter logistic models. NOTE: PBA = Paper-based assessment. For item j, aj represents the discriminatory power of the item, bj represents a location parameter related to item difficulty, cj represents the guessing parameter, and dji represents the category threshold parameter for category i. The c parameter value is assumed to be exactly zero and is not estimated for items scaled with the two-parameter logistic model. For item j, dji may not sum to zero because of rounding. The block naming conventions used in this table are described in the document 2018 Block Naming Conventions in Data Products and TDW .SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2018 Geography Assessment. | ||||||||||
Last updated 31 January 2023 (ML)