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NAEP Analysis and ScalingEstimation of NAEP Score ScalesNAEP Assessment IRT ParametersMathematics Assessment IRT Parameters → IRT Parameters for Items in the Algebra Subscale, Grade 12 Mathematics National Assessment, by Item and Block: 2015

NAEP Technical DocumentationIRT Parameters for Items in the Algebra Subscale, Grade 12 Mathematics National Assessment, by Item and Block: 2015

IRT parameters for items in the algebra subscale, grade 12 mathematics national assessment, by item and block: 2015
BlockItemNAEP ID aj bj cj dj1 dj2 dj3 dj4
M1
3M1836010.570.820.76-0.76
5M1965010.640.470.30
9M1764011.111.740.22
11M1861012.300.850.25
13M1858012.291.640.13
M2
5M3052011.451.110.18
7M3029010.950.460.23-0.23
9M3066010.910.820.12
11M3059CL0.511.591.72-3.492.83-1.06
14M3075010.551.35-0.150.15
M3
1M1971011.250.700.13
8M1934010.941.450.08-0.08
11M1751010.544.060.17
12M1833010.911.730.17
14M1792011.521.820.41-0.41
M4
6M1904010.98-0.450.15
8M1976010.841.000.50-0.50
10M1977011.311.290.18
14M1979011.240.090.09
M5
3M1773010.960.640.07-0.07
9M1826010.990.540.23
13M1852010.74-0.53
14M1980011.551.080.22
M6
3M1982012.04-0.540.33
4M1982021.360.220.08
5M1982032.63-0.310.29
7M1767011.041.420.13
14M1747011.591.280.17
M7
3M3110010.510.200.22
7M3077011.61-0.320.17
9M3115010.901.350.24
12M3096011.041.600.33
M8
1M1876011.33-0.270.14
7M1884012.261.160.15
9M1880010.780.19-0.600.60
M9
2M1929011.16-0.560.22
9M1923011.140.080.24
10M1988010.940.520.25
13M1855011.210.400.25
M10
7M1991011.991.240.17
8M1992010.511.33-4.154.15
9M1909010.620.960.10
10M1993011.921.910.28
11M1908010.900.981.21-1.21
M11
1M1843010.96-1.260.20
4M1807011.26-0.050.18
10M1765CL0.540.810.80-0.07-0.55-0.18
12M1892011.110.970.24
13M1831011.951.55
M12
2M1998011.120.880.20
6M1821010.781.930.32
7M1821021.441.640.07
10M2001010.980.410.17
12M1779011.121.570.36
M13
2M3062010.26-0.310.23
6M3011011.180.850.22
10M3016011.031.190.26
13M3021010.732.27-0.12-0.660.78
14M3030011.291.350.16
M14
2M3088010.830.260.16
4M3098010.96-0.350.19
10M3113011.551.850.21
† Not applicable; c parameters are not estimated for the two-parameter logistic model or generalized partial credit models, and d parameters are not estimated for two-parameter or three-parameter logistic models.
NOTE: 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.
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2015 Mathematics Assessment.

Last updated 01 December 2021 (ML)