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NAEP Analysis and ScalingEstimation of NAEP Score ScalesNAEP Assessment IRT ParametersCivics Assessment IRT Parameters → IRT Parameters for Items in the Univariate Scale, Grade 8 Civics National Assessment, by Block and Item: 2018

NAEP Technical DocumentationIRT Parameters for Items in the Univariate Scale, Grade 8 Civics National Assessment, by Block and Item: 2018

IRT parameters for items in the univariate scale, grade 8 civics DBA national assessment, by block and item: 2018
BlockItemNAEP ID aj bj cj dj1 dj2 dj3 dj4
C11P0421690.88-0.520.31
2P0421700.44-0.610.22
3P0421710.58-0.031.05-1.05
4P0421720.601.240.19
5P0512010.53-0.890.22
6P0421740.781.840.60-0.60
7P0421750.49-1.350.24
8P0421760.371.010.28
9P0421770.65-1.10
11P0539011.050.260.21
12P0515010.83-0.190.14
13P0421810.520.490.90-0.90
14P0421820.91-1.580.34
15P0421830.821.050.39
16P0421840.51-0.340.65-0.65
17P0421850.910.900.29
18P0421861.35-0.870.33
19P0421870.810.490.19
20P0421880.93-0.300.25
21P0516011.240.270.22
23P0412020.660.270.37-0.37
24P0412100.79-0.270.24
25P0519010.801.050.20
26P0412141.441.800.32
C21P0421500.97-0.660.36
2P0421511.130.540.23
3P0421521.06-0.32
4P0421530.930.600.32
5P0421541.13-0.250.23
6P0495010.780.16
7P0421561.210.530.21
8P0421571.27-0.090.19
9P0421580.510.461.36-1.36
10P0529010.811.760.25
11P0421601.430.860.24
12P0421611.700.050.27
13P0421620.810.880.20-0.20
14P0421631.591.190.32
15P0421640.801.510.21
16P0421651.540.120.19
17P0421661.000.600.44
18P0421671.09-1.160.31
19P0421681.000.440.37
20P0412030.75-0.930.26
21P0412040.450.970.26
22P0514010.621.290.74-0.74
23P0507010.680.300.35
24P0551010.93-0.220.21
25P0499011.42-0.030.20
28P0412010.670.540.22
C31P0413011.470.580.33
2P0413021.130.560.30
3P0413031.620.190.32
4P0413041.19-0.680.25
5P0628021.341.050.21
6P0628010.92-0.940.23
7P0412050.42-2.69
8P0413081.801.410.17
9P0413090.791.34
10P0413101.610.760.25
11P0413110.371.190.29
12P0413120.721.860.20
13P0413130.65-0.800.25
14P0413141.020.700.17
15P0413150.44-0.310.54-0.54
16P0413161.060.540.25
17P0413171.290.660.21
18P0413180.900.230.22
19P0413190.580.610.24
20P0521010.421.731.060.31-1.36
21P0412170.561.310.29
22P0412151.21-0.450.21
23P0412161.510.330.15
24P0412060.950.340.13
25P0412091.590.890.32
26P0534011.301.040.26
C41P0409010.85-0.660.32
2P0409021.061.080.14
3P0409030.510.480.20-0.20
4P0409041.100.370.23
5P0537011.050.090.42
6P0409061.171.77
7P0409070.791.160.23
8P0409081.01-0.170.25
9P0409091.28-0.330.29
10P0409100.531.521.15-1.15
11P0409110.431.040.29
12P0409121.241.450.19
13P0409130.670.500.44-0.44
14P0409141.170.560.18
15P0409152.031.510.30
16P0409161.031.000.16
17P0505010.581.170.350.40-0.75
18P0523011.060.810.30
19P0409191.320.280.22
20P0538010.572.91
21P0549011.290.220.18
22P0533010.94-0.990.27
23P0487011.200.870.21
24P0494011.731.630.34
C51P0411010.66-0.650.32
2P0411020.561.420.28-0.28
3P0411030.840.440.16
4P0411040.642.140.28
5P0411050.621.270.29
6P0411060.510.41
7P0411071.100.100.32
8P0411081.24-0.180.21
9P0412181.420.640.36
10P0411100.601.650.27
11P0411111.011.170.21-0.21
12P0411120.45-1.120.32
13P0411130.780.400.35
14P0411141.092.140.11
15P0411151.081.270.22
16P0411160.830.910.48-0.48
17P0411171.00-1.130.33
18P0411182.101.310.23
19P0411190.900.010.33
20P0491011.261.410.29
22P0412191.02-0.460.26
23P0412080.860.300.31
24P0543011.021.210.43
C61P0652MS0.72-0.26
2P0655010.30-1.03-0.830.83
3P0636MS0.49-0.86
4P0694010.67-1.020.31
5P0642010.43-0.800.60-0.50-0.09
6P0663011.100.060.33
7P0680010.650.410.48-0.48
8P0657MS0.940.48
9P0708010.89-1.98
10P0709MS0.38-0.992.57-2.57
11P0665010.55-0.090.08-0.08
12P0676010.961.44
13P0687010.981.190.35
15P0689MS0.980.78
16P0647011.260.290.28
17P0703011.340.340.33
18P0702010.711.080.48-0.48
19P0677MS0.46-0.021.31-1.31
20P0666011.21-0.460.26
C71P0656MS0.37-1.53
2P0630010.86-0.960.26
3P0662010.36-1.39-1.261.26
4P0692010.611.430.28
5P0646010.571.370.68-0.68
6P0650MS0.66-0.740.76-0.76
7P0691010.630.040.15-0.15
8P0678MS0.670.86
9P0679MS0.660.74
10P0659CL0.530.801.010.57-1.58
13P0693011.12-0.260.20
14P0714MS0.63-0.560.41-0.41
15P0711011.190.450.30
16P0637CL0.631.17-0.070.07
17P0633011.550.860.35
18P0638010.870.360.29
19P0671010.670.47-0.130.13
20P0706011.210.230.22
† 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: 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 PDF File .
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2018 Civics Assessment.

IRT parameters for items in the univariate scale, grade 8 civics PBA national assessment, by block and item: 2018
BlockItemNAEP ID aj bj cj dj1 dj2 dj3 dj4
C31P0421690.68-1.210.27
2P0421700.39-0.720.21
3P042171 0.55-0.280.85-0.85
4P0421720.601.350.20
5P0421730.761.100.33
6P0421740.932.020.70-0.70
7P0421750.39-1.640.26
8P0421760.370.690.23
9P0421770.41-0.580.18-0.18
10P0421781.600.930.27
11P0421792.051.050.21
12P0421800.411.070.24
13P0421810.490.690.95-0.95
14P0421820.75-1.950.33
15P0421830.761.210.34
16P0421840.52-0.611.02-1.02
17P0421850.701.020.28
18P0421861.15-0.860.37
19P0421870.710.560.17
20P0421881.400.160.41
C41P0483011.471.190.37
2P0484010.79-0.430.53
3P0487011.430.710.24
4P0538010.331.92-0.800.80
5P0515010.76-0.290.25
6P0534011.080.570.20
7P0514010.571.120.98-0.98
9P0506010.620.060.23
10P0491011.601.000.26
11P0494011.501.210.31
12P0521010.431.701.230.00-1.23
13P0544011.241.730.47
14P0512010.56-0.560.22
15P0541010.640.101.15-1.15
16P0546010.760.390.26
17P0529010.951.510.27
18P0499011.44-0.160.19
C51P0409010.62-1.180.33
2P0409021.141.020.14
3P0409030.611.66
4P0409041.090.200.14
5P0409051.180.320.30
6P0409060.611.63-0.660.66
7P0409070.810.860.22
8P0409080.81-0.350.22
9P0409091.34-0.460.26
10P0409100.451.831.45-1.45
11P0409110.431.170.32
12P0409121.461.480.23
13 P040913 0.750.520.71-0.71
14P0409140.960.640.18
15P0409151.241.390.28
16P0409161.180.990.24
17P0409170.830.770.15
18P0409181.010.030.37
19P0409191.260.270.23
C61P0539011.220.420.24
2P0523010.720.810.26
3P0492010.57-0.170.73-0.73
4P0490010.660.780.29
5P0543010.840.930.40
6P0505010.490.870.300.36-0.66
7P0522011.080.010.23
8P0537010.79-0.260.33
9P0495010.680.860.28-0.28
10P0516011.310.220.17
11P0504011.320.870.32
12P0551010.77-0.150.24
13P0548010.550.78-0.880.88
14P0549011.130.030.22
15P0507010.610.650.36
16P0622010.680.830.79-0.79
17P0519010.981.090.24
18P0533010.97-1.120.27
19P0526011.05-0.280.34
C71P0411010.39-1.330.25
2P0411020.541.530.46-0.46
3P0411031.020.350.18
4P0411041.451.240.28
5P0411050.721.180.25
6P0411060.451.891.86-1.86
7P0411071.360.160.39
8P0411080.93-0.160.25
10P0411101.991.390.31
11P0411110.871.120.20-0.20
12P0411120.40-1.610.27
13P0411130.960.660.38
15P0411151.071.340.20
16P0411160.830.990.63-0.63
17P0411170.85-1.250.29
18P0411181.511.340.23
19P0411191.110.160.34
C81P0412010.550.130.25
2P0412020.700.190.50-0.50
3P0412030.47-1.820.28
5P0412050.23-1.67-1.391.39
6P0412061.030.220.17
7P0412071.211.000.23
8P0412080.770.190.30
9P0412091.190.580.30
10P0412100.53-0.200.25
11P0412110.691.790.27
12P0412120.960.210.26
13P0412130.541.691.180.75-1.93
14P0412141.711.390.32
15P0412151.03-0.430.23
16P0412161.470.520.18
17P0412170.531.470.27
18P0412181.410.780.34
19P0412190.96-0.560.21
C91P0413011.040.390.41
2P0413020.950.310.21
3P0413031.420.020.29
4P0413041.76-0.350.34
5P0628021.210.810.16
6P0628010.99-0.880.29
7P0413070.870.840.98-0.63-0.34
8P0413081.471.420.16
9P0413090.791.17
10P0413101.600.670.26
11P0413110.350.740.25
12P0413120.731.970.19
13P0413130.86-0.740.29
14P0413141.190.840.24
15P0413150.48-0.380.64-0.64
16P0413161.350.390.29
17P0413171.090.630.17
18P0413180.870.330.24
19P0413190.550.420.22
C101P0421500.82-0.910.40
2P0421511.300.310.24
3P0421520.640.220.66-0.66
4P0421531.270.720.36
5P0421541.16-0.370.25
6P0421550.60-0.040.920.48-1.41
7P0421561.460.440.17
8P0421571.390.020.24
9P0421580.440.491.54-1.54
10P0421591.391.480.19
11P0421600.990.900.30
12P0421611.480.040.22
13P0421620.830.880.19-0.19
14P0421631.501.020.28
15P0421640.791.560.21
16P0421651.290.090.17
17P0421660.840.500.34
18P0421671.01-1.090.42
19P0421680.960.220.35
† 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 PDF File .
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2018 Civics Assessment.


Last updated 26 January 2023 (ML)