#Background for re-analysis

Item naming was faulty in previous version. Some items were duplicated, and counted as two different items. The issue was with “Kopi.av.Kopi.av” etcetera

Booklets and items

A total number of 2054 students participated in this pilot-study, responding to a total of 378 items.

The the number of observations per item:
item1 observation1 item2 observation2 item3 observation3
ord_001_dag_2 259 ord_193_kort_2 487 ord_406_skrape_1 250
ord_003_dag_500 463 ord_193_kort_200 224 ord_408_skrape_200 248
ord_005_tak_2 259 ord_194_kort_1 259 ord_411_salve_500 336
ord_006_tak_1 245 ord_195_kort_500 250 ord_412_salve_200 484
ord_007_tak_500 248 ord_198_natt_1 250 ord_414_lykten_1 245
ord_010_sak_1 586 ord_199_natt_500 560 ord_416_lykten_200 259
ord_011_sak_500 248 ord_200_natt_200 498 ord_420_mynter_200 504
ord_012_sak_200 259 ord_202_uret_1 239 ord_422_drops_1 250
ord_013lam_2 259 ord_206_leke_1 259 ord_423_drops_500 245
ord_014lam_1 239 ord_207_leke_500 498 ord_424_drops_200 259
ord_015lam_500 336 ord_208_leke_200 336 ord_427_våren_500 253
ord_018_rar_1 586 ord_210_høne_1 336 ord_428_våren_200 224
ord_019_rar_500 472 ord_211_høne_500 492 ord_430_dukken_1 245
ord_020_rar_200 259 ord_212_høne_200 504 ord_431_dukken_500 248
ord_021_far_2 253 ord_213_tann_2 250 ord_432_dukken_200 253
ord_022_far_1 248 ord_215_tann_500 253 ord_435_sukker_500 239
ord_023_far_500 245 ord_216_tann_200 498 ord_436_sukker_200 504
ord_025_lat_2 253 ord_217_lang_2 336 ord_442_luktet_1 224
ord_027_lat_500 224 ord_218_lang_1 245 ord_443_luktet_500 245
ord_028_lat_200 239 ord_219_lang_500 487 ord_444_luktet_200 253
ord_029_hav_2 253 ord_220_lang_200 762 ord_451_dusten_500 224
ord_031_hav_500 493 ord_221_bart_2 253 ord_452_dusten_200 487
ord_034_lek_1 253 ord_223_bart_500 469 ord_455_skøyter_500 245
ord_035_lek_500 239 ord_224_bart_200 498 ord_456_skøyter_200 737
ord_038_mel_1 259 ord_226_bråk_1 224 ord_458_tenker_1 224
ord_039_mel_500 336 ord_227_bråk_500 586 ord_459_tenker_500 239
ord_042_pen_1 259 ord_228_bråk_200 487 ord_460_tenker_200 245
ord_043_pen_500 250 ord_230_brød_1 253 ord_462_krangle_1 259
ord_044_pen_200 245 ord_231_brød_500 581 ord_464_krangle_200 586
ord_046_fem_1 253 ord_232_brød_200 224 ord_467_trasket_500 757
ord_047_fem_500 248 ord_233_hest_2 224 ord_468_trasket_200 586
ord_049_ser_2 250 ord_234_hest_1 250 ord_470_vinduer_1 259
ord_050_ser_1 248 ord_235_hest_500 259 ord_471_vinduer_500 487
ord_051_ser_500 492 ord_236_hest_200 239 ord_472_vinduer_200 813
ord_053_les_2 484 ord_239_såpe_500 2054 ord_478_marsjerer_1 250
ord_055_les_500 253 ord_241_bord_2 250 ord_479_marsjerer_500 746
ord_057_fat_2 250 ord_242_bord_1 239 ord_480_marsjerer_200 253
ord_059_fat_500 259 ord_243_bord_500 248 ord_482_kantarell_1 250
ord_060_fat_200 253 ord_244_bord_200 253 ord_483_kantarell_500 245
ord_061_fin_2 224 ord_246_rote_1 224 ord_484_kantarell_200 512
ord_063_fin_500 336 ord_247_rote_500 825 ord_486_tallerken_1 336
ord_067_rir_500 250 ord_248_rote_200 477 ord_494_glitret_1 336
ord_068_rir_200 253 ord_254_klam_1 224 ord_495_glitret_500 245
ord_071_ris_500 336 ord_255_klam_500 507 ord_496_glitret_200 259
ord_072_ris_200 245 ord_256_klam_200 336 ord_499_praktisk_500 834
ord_073_lov_2 245 ord_257_fyre_2 224 ord_500_praktisk_200 743
ord_074_lov_1 224 ord_258_fyre_1 245 ord_503_speilet_500 734
ord_075_lov_500 253 ord_259_fyre_500 259 ord_504_speilet_200 819
ord_079_bil_500 495 ord_260_fyre_200 248 ord_506_planter_1 253
ord_080_bil_200 336 ord_262_slått_1 336 ord_516_kanonen_200 224
ord_082_kos_1 224 ord_263_slått_500 498 ord_519_fantastisk_500 487
ord_083_kos_500 250 ord_266_frosk_1 259 ord_520_fantastisk_200 477
ord_085_rop_2 248 ord_267_frosk_500 586 ord_523_transport_500 498
ord_087_rop_500 224 ord_268_frosk_200 245 ord_524_transport_200 224
ord_088_rop_200 239 ord_271_sykle_500 512 ord_530_prestene_1 245
ord_090_hun_1 239 ord_272_sykle_200 250 ord_531_prestene_500 1047
ord_091_hun_500 224 ord_274_lekser_1 248 ord_532_prestene_200 512
ord_092_hun_200 248 ord_275_lekser_500 512 ord_538_instrument_1 248
ord_093_bur_2 248 ord_278_klokke_1 224 ord_539_instrument_500 245
ord_095_bur_500 484 ord_279_klokke_500 504 ord_540_instrument_200 259
ord_096_bur_200 224 ord_280_klokke_200 250 ord_542_balansere_1 484
ord_097_dyr_2 250 ord_282_synge_1 248 ord_544_balansere_200 259
ord_098_dyr_1 245 ord_283_synge_500 336 ord_547_direkte_500 504
ord_099_dyr_500 336 ord_284_synge_200 512 ord_548_direkte_200 810
ord_103_sør_500 495 ord_287_arver_500 2054 ord_554_annerledes_1 253
ord_104_sør_200 224 ord_290_skolen_1 2054 ord_555_annerledes_500 498
ord_105_dør_2 484 ord_295_hunden_500 487 ord_556_annerledes_200 224
ord_107_dør_500 253 ord_296_hunden_200 810 ord_559_stativene_500 560
ord_108_dør_200 336 ord_299_padle_500 259 ord_560_stativene_200 498
ord_111_søl_500 259 ord_300_padle_200 484 ord_563_stranden_500 504
ord_113_bål_2 248 ord_302_esker_1 259 ord_564_stranden_200 560
ord_115_bål_500 239 ord_303_esker_500 560 ord_567_skjelett_500 253
ord_116_bål_200 250 ord_304_esker_200 498 ord_570_strutsene_1 224
ord_117_bra_2 336 ord_307_planke_500 504 ord_575_spraglete_500 560
ord_119_bra_500 253 ord_310_niste_1 336 ord_576_spraglete_200 239
ord_120_bra_200 248 ord_311_niste_500 498 ord_579_uhøflig_500 477
ord_121_arm_2 239 ord_312_niste_200 512 ord_580_uhøflig_200 586
ord_123_arm_500 259 ord_316_bamse_200 2054 ord_583_hemmelig_500 504
ord_124_arm_200 250 ord_318_hjerne_1 253 ord_584_hemmelig_200 498
ord_125_sol_2 2054 ord_319_hjerne_500 250 ord_588_slåsskamp_200 2054
ord_129_mus_2 560 ord_320_hjerne_200 813 ord_591_eksplosjon_500 253
ord_131_mus_500 259 ord_323_lappen_500 336 ord_592_eksplosjon_200 560
ord_133_bok_2 2054 ord_324_lappen_200 501 ord_599_pasning_500 504
ord_137_syn_2 560 ord_327_spruter_500 586 ord_600_pasning_200 224
ord_139_syn_500 259 ord_328_spruter_200 483 ord_606_ordentlig_1 224
ord_141_dele_2 259 ord_330_bukser_1 253 ord_607_ordentlig_500 253
ord_143_dele_500 711 ord_331_bukser_500 484 ord_608_ordentlig_200 248
ord_144_dele_200 245 ord_332_bukser_200 560 ord_611_konsentrasjon_500 224
ord_145_lege_2 248 ord_335_genser_500 487 ord_612_konsentrasjon_200 487
ord_146_lege_1 336 ord_336_genser_200 586 ord_622_kraftverk_1 245
ord_147_lege_500 469 ord_338_bakke_1 487 ord_623_kraftverk_500 224
ord_148_lege_200 751 ord_339_bakke_500 259 ord_624_kraftverk_200 248
ord_150_gate_1 259 ord_340_bakke_200 336 ord_626_overraskelsen_1 487
ord_151_gate_500 586 ord_342_hjelm_1 336 ord_627_overraskelsen_500 245
ord_152_gate_200 248 ord_343_hjelm_500 259 ord_628_overraskelsen_200 512
ord_153_hale_2 336 ord_344_hjelm_200 487 ord_634_kalenderne_1 253
ord_154_hale_1 245 ord_347_bilde_500 477 ord_638_systemene_1 239
ord_155_hale_500 512 ord_348_bilde_200 498 ord_639_systemene_500 512
ord_156_hale_200 250 ord_351_glade_500 253 ord_640_systemene_200 248
ord_157_møte_2 498 ord_352_glade_200 586 ord_644_kikkertene_200 245
ord_159_møte_500 463 ord_354_kosten_1 259 ord_650_skyskraperen_1 248
ord_160_møte_200 250 ord_355_kosten_500 560 ord_651_skyskraperen_500 586
ord_162_nyse_1 253 ord_356_kosten_200 239 ord_652_skyskraperen_200 253
ord_163_nyse_500 493 ord_359_visper_500 250 ord_654_tørklær_1 250
ord_164_nyse_200 586 ord_360_visper_200 336 ord_655_tørklær_500 512
ord_166_rope_1 2054 ord_362_kornet_1 250 ord_656_tørklær_200 487
ord_169_våte_2 239 ord_363_kornet_500 248 ord_658_forklærne_1 336
ord_170_våte_1 253 ord_367_silke_500 484 ord_659_forklærne_500 239
ord_171_våte_500 586 ord_371_slave_500 477 ord_660_forklærne_200 253
ord_172_våte_200 248 ord_372_slave_200 487 ord_670_kvalmende_1 224
ord_174_kino_1 250 ord_375_teller_500 253 ord_671_kvalmende_500 336
ord_175_kino_500 498 ord_376_teller_200 484 ord_672_kvalmende_200 253
ord_176_kino_200 245 ord_378_brøler_1 239 ord_690_alarmanlegg_1 253
ord_178_hjul_1 336 ord_379_brøler_500 498 ord_692_alarmanlegg_200 245
ord_179_hjul_500 725 ord_380_brøler_200 504 ord_699_avslappende_500 484
ord_180_hjul_200 239 ord_383_gnager_500 245 ord_700_avslappende_200 586
ord_181_peis_2 504 ord_384_gnager_200 477 ord_708_kontraktene_200 248
ord_182_peis_1 487 ord_387_eksem_500 250 ord_710_forvekslinger_1 259
ord_183_peis_500 250 ord_390_kloden_1 253 ord_712_forvekslinger_200 239
ord_184_peis_200 560 ord_391_kloden_500 245 ord_722_legetimene_1 259
ord_186_sand_1 248 ord_392_kloden_200 560 ord_723_legetimene_500 586
ord_187_sand_500 504 ord_394_flaske_1 239 ord_744_allsidighet_200 484
ord_188_sand_200 224 ord_395_flaske_500 224 ord_748_fyrstikkeske_200 484
ord_190_våge_1 248 ord_396_flaske_200 498 ord_750_skylde_1 245
ord_191_våge_500 253 ord_399_styrke_500 239 ord_750_skylde_500 224
ord_192_våge_200 336 ord_400_styrke_200 477 sand_188_sand_200 253

Level of difficulty

We have 378 dichotomous items, and 0 polytomous items. Here is the the distribution of percentage correct for the dichotomous items:

IRT modeling

Item estimation of model 2PL. The resulting test information curve is as follows:

Item parameters a (discrimination) and d (difficulty)
a d
ord_001_dag_2 1.6 -1.4
ord_003_dag_500 2.3 -0.8
ord_005_tak_2 2.1 -1.8
ord_006_tak_1 1.8 -1.9
ord_007_tak_500 1.5 -2.3
ord_010_sak_1 1.7 -1.9
ord_011_sak_500 0.9 -3.1
ord_012_sak_200 2.7 -0.9
ord_013lam_2 1.9 -1.7
ord_014lam_1 1.2 -1.9
ord_015lam_500 1.6 -2.0
ord_018_rar_1 1.5 -2.0
ord_019_rar_500 2.2 -1.3
ord_020_rar_200 3.6 -0.5
ord_021_far_2 1.7 -2.1
ord_022_far_1 1.5 -2.3
ord_023_far_500 2.7 -1.1
ord_025_lat_2 2.6 -1.4
ord_027_lat_500 2.2 -1.2
ord_028_lat_200 1.8 -0.5
ord_029_hav_2 1.5 -1.7
ord_031_hav_500 1.6 -1.5
ord_034_lek_1 0.4 -7.7
ord_035_lek_500 3.3 -1.3
ord_038_mel_1 2.0 -1.6
ord_039_mel_500 1.5 -1.9
ord_042_pen_1 1.8 -1.7
ord_043_pen_500 2.5 -1.4
ord_044_pen_200 1.3 -1.6
ord_046_fem_1 0.7 -3.8
ord_047_fem_500 1.0 -2.1
ord_049_ser_2 2.1 -2.1
ord_050_ser_1 1.5 -2.3
ord_051_ser_500 1.7 -1.4
ord_053_les_2 1.9 -2.1
ord_055_les_500 0.0 -88.0
ord_057_fat_2 1.4 -2.0
ord_059_fat_500 2.0 -1.2
ord_060_fat_200 2.0 -0.9
ord_061_fin_2 1.7 -2.3
ord_063_fin_500 1.4 -2.1
ord_067_rir_500 2.3 -1.3
ord_068_rir_200 1.6 -1.1
ord_071_ris_500 1.5 -2.2
ord_072_ris_200 2.5 -1.2
ord_073_lov_2 1.7 -1.9
ord_074_lov_1 1.6 -2.0
ord_075_lov_500 1.4 -2.2
ord_079_bil_500 1.3 -0.7
ord_080_bil_200 1.3 -0.6
ord_082_kos_1 1.7 -1.8
ord_083_kos_500 2.5 -1.3
ord_085_rop_2 0.7 -5.3
ord_087_rop_500 4.0 -1.2
ord_088_rop_200 3.3 -0.7
ord_090_hun_1 1.3 -1.8
ord_091_hun_500 2.1 -1.2
ord_092_hun_200 1.4 -1.2
ord_093_bur_2 2.1 -1.1
ord_095_bur_500 2.1 -0.8
ord_096_bur_200 4.1 -0.5
ord_097_dyr_2 1.6 -1.9
ord_098_dyr_1 1.6 -1.8
ord_099_dyr_500 2.3 -1.5
ord_103_sør_500 1.9 -1.3
ord_104_sør_200 3.0 -0.7
ord_105_dør_2 1.3 -2.1
ord_107_dør_500 1.5 -1.3
ord_108_dør_200 1.8 -1.2
ord_111_søl_500 2.2 -1.1
ord_113_bål_2 1.5 -1.6
ord_115_bål_500 2.3 -0.9
ord_116_bål_200 3.8 -0.4
ord_117_bra_2 1.6 -2.0
ord_119_bra_500 2.1 -1.2
ord_120_bra_200 2.8 -1.0
ord_121_arm_2 1.8 -1.9
ord_123_arm_500 2.9 -1.3
ord_124_arm_200 2.9 -0.7
ord_125_sol_2 1.5 -2.2
ord_129_mus_2 1.7 -2.1
ord_131_mus_500 2.5 -1.2
ord_133_bok_2 1.7 -2.2
ord_137_syn_2 1.3 -2.3
ord_139_syn_500 2.9 -1.2
ord_141_dele_2 2.0 -1.5
ord_143_dele_500 3.1 -0.8
ord_144_dele_200 3.8 -0.4
ord_145_lege_2 1.9 -1.6
ord_146_lege_1 1.4 -1.4
ord_147_lege_500 2.6 -1.0
ord_148_lege_200 2.6 -0.5
ord_150_gate_1 2.0 -1.6
ord_151_gate_500 1.9 -1.2
ord_152_gate_200 1.6 -1.1
ord_153_hale_2 1.5 -2.5
ord_154_hale_1 3.7 -0.9
ord_155_hale_500 2.0 -1.4
ord_156_hale_200 2.2 -0.7
ord_157_møte_2 0.9 -2.6
ord_159_møte_500 2.3 -0.8
ord_160_møte_200 2.7 -0.5
ord_162_nyse_1 2.1 -1.4
ord_163_nyse_500 3.7 -0.8
ord_164_nyse_200 3.3 -0.5
ord_166_rope_1 1.8 -1.8
ord_169_våte_2 1.4 -2.1
ord_170_våte_1 0.9 -2.9
ord_171_våte_500 2.7 -1.0
ord_172_våte_200 1.7 -1.2
ord_174_kino_1 1.7 -1.5
ord_175_kino_500 2.8 -0.9
ord_176_kino_200 2.1 -0.7
ord_178_hjul_1 1.0 -2.6
ord_179_hjul_500 2.1 -1.3
ord_180_hjul_200 3.4 -0.6
ord_181_peis_2 2.0 -1.6
ord_182_peis_1 1.8 -1.8
ord_183_peis_500 2.3 -1.1
ord_184_peis_200 3.0 -0.7
ord_186_sand_1 1.6 -1.5
ord_187_sand_500 2.9 -1.1
ord_188_sand_200 3.7 -0.5
ord_190_våge_1 2.6 -1.1
ord_191_våge_500 2.3 -0.8
ord_192_våge_200 3.2 -0.3
ord_193_kort_2 1.4 -2.0
ord_193_kort_200 2.8 -0.5
ord_194_kort_1 1.7 -1.4
ord_195_kort_500 3.5 -0.8
ord_198_natt_1 2.3 -1.7
ord_199_natt_500 2.6 -1.3
ord_200_natt_200 2.6 -0.7
ord_202_uret_1 1.5 -1.5
ord_206_leke_1 2.0 -1.4
ord_207_leke_500 1.9 -1.2
ord_208_leke_200 3.2 -0.4
ord_210_høne_1 1.3 -1.8
ord_211_høne_500 2.2 -0.9
ord_212_høne_200 2.8 -0.5
ord_213_tann_2 2.0 -1.8
ord_215_tann_500 1.2 -2.4
ord_216_tann_200 2.5 -0.7
ord_217_lang_2 1.2 -2.1
ord_218_lang_1 3.2 -1.0
ord_219_lang_500 2.4 -0.9
ord_220_lang_200 2.0 -0.7
ord_221_bart_2 1.9 -1.2
ord_223_bart_500 3.2 -0.6
ord_224_bart_200 2.9 -0.2
ord_226_bråk_1 1.4 -1.4
ord_227_bråk_500 2.1 -0.8
ord_228_bråk_200 2.6 -0.5
ord_230_brød_1 0.8 -5.1
ord_231_brød_500 2.0 -1.5
ord_232_brød_200 3.7 -0.6
ord_233_hest_2 1.5 -2.0
ord_234_hest_1 1.8 -1.4
ord_235_hest_500 2.8 -1.2
ord_236_hest_200 2.5 -0.8
ord_239_såpe_500 2.1 -1.0
ord_241_bord_2 1.3 -1.8
ord_242_bord_1 1.7 -1.2
ord_243_bord_500 4.4 -0.7
ord_244_bord_200 2.2 -0.7
ord_246_rote_1 1.7 -1.6
ord_247_rote_500 2.1 -1.2
ord_248_rote_200 3.2 -0.7
ord_254_klam_1 1.4 -1.2
ord_255_klam_500 2.2 -0.5
ord_256_klam_200 3.1 -0.2
ord_257_fyre_2 1.4 -1.8
ord_258_fyre_1 0.7 -3.6
ord_259_fyre_500 2.3 -1.3
ord_260_fyre_200 2.0 -1.0
ord_262_slått_1 1.3 -1.0
ord_263_slått_500 1.8 -0.4
ord_266_frosk_1 1.6 -1.1
ord_267_frosk_500 2.0 -0.6
ord_268_frosk_200 3.6 -0.3
ord_271_sykle_500 2.9 -1.1
ord_272_sykle_200 2.4 -0.6
ord_274_lekser_1 1.1 -1.1
ord_275_lekser_500 1.6 -1.0
ord_278_klokke_1 1.6 -0.7
ord_279_klokke_500 2.3 -0.3
ord_280_klokke_200 3.4 -0.1
ord_282_synge_1 2.3 -1.0
ord_283_synge_500 3.2 -0.5
ord_284_synge_200 3.3 -0.4
ord_287_arver_500 1.6 -0.8
ord_290_skolen_1 1.5 -1.3
ord_295_hunden_500 1.7 0.1
ord_296_hunden_200 2.7 0.2
ord_299_padle_500 2.6 -0.5
ord_300_padle_200 3.4 -0.3
ord_302_esker_1 1.2 -0.9
ord_303_esker_500 1.6 -0.3
ord_304_esker_200 1.6 0.2
ord_307_planke_500 2.0 -0.9
ord_310_niste_1 2.3 -0.8
ord_311_niste_500 2.5 -0.4
ord_312_niste_200 3.1 -0.2
ord_316_bamse_200 2.7 -0.5
ord_318_hjerne_1 2.3 -1.0
ord_319_hjerne_500 2.4 -0.4
ord_320_hjerne_200 2.2 -0.3
ord_323_lappen_500 1.8 -0.8
ord_324_lappen_200 1.4 -0.8
ord_327_spruter_500 2.1 0.6
ord_328_spruter_200 2.4 0.7
ord_330_bukser_1 1.9 -0.9
ord_331_bukser_500 2.6 -0.6
ord_332_bukser_200 2.9 -0.3
ord_335_genser_500 2.3 -0.5
ord_336_genser_200 2.4 -0.2
ord_338_bakke_1 1.7 -1.6
ord_339_bakke_500 2.4 -1.0
ord_340_bakke_200 2.0 -1.0
ord_342_hjelm_1 1.9 -0.5
ord_343_hjelm_500 1.6 -0.2
ord_344_hjelm_200 2.2 0.2
ord_347_bilde_500 1.7 0.2
ord_348_bilde_200 2.3 0.3
ord_351_glade_500 2.4 -0.9
ord_352_glade_200 3.3 -0.5
ord_354_kosten_1 2.1 -1.2
ord_355_kosten_500 1.9 -0.9
ord_356_kosten_200 1.5 -0.7
ord_359_visper_500 2.0 0.1
ord_360_visper_200 2.6 0.5
ord_362_kornet_1 1.4 -0.2
ord_363_kornet_500 1.6 0.2
ord_367_silke_500 1.2 0.0
ord_371_slave_500 2.2 0.0
ord_372_slave_200 2.5 0.3
ord_375_teller_500 2.8 -0.7
ord_376_teller_200 3.0 -0.4
ord_378_brøler_1 1.7 -1.2
ord_379_brøler_500 3.1 -0.5
ord_380_brøler_200 2.9 -0.3
ord_383_gnager_500 1.7 -0.1
ord_384_gnager_200 1.6 0.4
ord_387_eksem_500 1.6 -0.6
ord_390_kloden_1 2.3 -0.5
ord_391_kloden_500 3.0 -0.3
ord_392_kloden_200 3.0 0.1
ord_394_flaske_1 1.1 0.2
ord_395_flaske_500 2.6 0.3
ord_396_flaske_200 1.9 0.6
ord_399_styrke_500 2.1 0.0
ord_400_styrke_200 1.7 0.3
ord_406_skrape_1 0.9 -0.2
ord_408_skrape_200 1.4 0.8
ord_411_salve_500 1.8 0.2
ord_412_salve_200 1.9 0.5
ord_414_lykten_1 1.5 -1.2
ord_416_lykten_200 1.9 -0.6
ord_420_mynter_200 1.8 -0.8
ord_422_drops_1 1.5 -1.3
ord_423_drops_500 3.3 -0.8
ord_424_drops_200 3.2 -0.4
ord_427_våren_500 1.6 -1.1
ord_428_våren_200 3.1 -0.3
ord_430_dukken_1 1.4 -1.4
ord_431_dukken_500 1.2 -1.2
ord_432_dukken_200 2.0 -0.5
ord_435_sukker_500 3.2 -1.0
ord_436_sukker_200 2.3 -0.8
ord_442_luktet_1 1.2 -0.2
ord_443_luktet_500 1.6 0.0
ord_444_luktet_200 1.9 0.5
ord_451_dusten_500 2.0 -0.6
ord_452_dusten_200 1.6 -0.7
ord_455_skøyter_500 2.9 0.1
ord_456_skøyter_200 2.6 0.2
ord_458_tenker_1 1.8 -1.0
ord_459_tenker_500 4.2 -0.3
ord_460_tenker_200 3.8 -0.1
ord_462_krangle_1 2.1 -0.6
ord_464_krangle_200 3.5 -0.1
ord_467_trasket_500 2.6 0.1
ord_468_trasket_200 2.7 0.3
ord_470_vinduer_1 1.3 -1.0
ord_471_vinduer_500 2.1 -0.7
ord_472_vinduer_200 2.1 -0.2
ord_478_marsjerer_1 1.4 -0.7
ord_479_marsjerer_500 3.3 -0.2
ord_480_marsjerer_200 2.3 0.1
ord_482_kantarell_1 1.5 -1.0
ord_483_kantarell_500 2.0 -0.5
ord_484_kantarell_200 1.9 0.1
ord_486_tallerken_1 1.1 -1.3
ord_494_glitret_1 2.5 -0.5
ord_495_glitret_500 2.6 -0.2
ord_496_glitret_200 2.5 0.1
ord_499_praktisk_500 2.2 0.1
ord_500_praktisk_200 2.4 0.4
ord_503_speilet_500 2.0 -0.7
ord_504_speilet_200 2.8 -0.2
ord_506_planter_1 1.0 -0.7
ord_516_kanonen_200 1.8 0.9
ord_519_fantastisk_500 1.4 -0.3
ord_520_fantastisk_200 1.8 -0.1
ord_523_transport_500 2.4 -0.7
ord_524_transport_200 2.0 -0.5
ord_530_prestene_1 1.6 -0.4
ord_531_prestene_500 1.9 0.0
ord_532_prestene_200 2.0 0.4
ord_538_instrument_1 2.4 -0.6
ord_539_instrument_500 2.6 -0.2
ord_540_instrument_200 2.0 -0.1
ord_542_balansere_1 2.6 -0.4
ord_544_balansere_200 2.4 0.4
ord_547_direkte_500 2.6 -0.3
ord_548_direkte_200 3.0 -0.1
ord_554_annerledes_1 2.9 -0.5
ord_555_annerledes_500 2.5 -0.6
ord_556_annerledes_200 2.7 -0.1
ord_559_stativene_500 3.2 -0.1
ord_560_stativene_200 2.0 0.1
ord_563_stranden_500 2.8 -0.3
ord_564_stranden_200 2.7 -0.1
ord_567_skjelett_500 1.0 -0.5
ord_570_strutsene_1 1.5 -0.3
ord_575_spraglete_500 2.3 0.3
ord_576_spraglete_200 1.9 0.6
ord_579_uhøflig_500 3.4 0.0
ord_580_uhøflig_200 2.9 0.2
ord_583_hemmelig_500 2.9 -0.8
ord_584_hemmelig_200 2.7 -0.7
ord_588_slåsskamp_200 1.9 -0.2
ord_591_eksplosjon_500 2.1 0.1
ord_592_eksplosjon_200 2.7 0.4
ord_599_pasning_500 2.6 -0.6
ord_600_pasning_200 2.9 -0.2
ord_606_ordentlig_1 2.4 -1.1
ord_607_ordentlig_500 2.8 -0.7
ord_608_ordentlig_200 2.7 -0.6
ord_611_konsentrasjon_500 2.0 -0.1
ord_612_konsentrasjon_200 1.3 0.0
ord_622_kraftverk_1 3.1 -0.3
ord_623_kraftverk_500 3.1 0.0
ord_624_kraftverk_200 2.1 0.3
ord_626_overraskelsen_1 1.4 -0.8
ord_627_overraskelsen_500 1.4 -0.4
ord_628_overraskelsen_200 1.9 0.2
ord_634_kalenderne_1 2.6 -0.5
ord_638_systemene_1 2.6 -0.6
ord_639_systemene_500 2.8 -0.2
ord_640_systemene_200 2.5 0.1
ord_644_kikkertene_200 1.4 0.7
ord_650_skyskraperen_1 1.3 -0.2
ord_651_skyskraperen_500 1.6 0.3
ord_652_skyskraperen_200 1.5 0.9
ord_654_tørklær_1 1.9 -0.3
ord_655_tørklær_500 2.3 0.2
ord_656_tørklær_200 2.3 0.4
ord_658_forklærne_1 1.6 -0.8
ord_659_forklærne_500 2.8 -0.4
ord_660_forklærne_200 1.8 -0.1
ord_670_kvalmende_1 1.8 -0.6
ord_671_kvalmende_500 3.1 0.0
ord_672_kvalmende_200 2.9 0.2
ord_690_alarmanlegg_1 1.4 -0.7
ord_692_alarmanlegg_200 1.9 0.3
ord_699_avslappende_500 1.8 -0.7
ord_700_avslappende_200 1.8 -0.5
ord_708_kontraktene_200 1.3 1.2
ord_710_forvekslinger_1 1.4 0.2
ord_712_forvekslinger_200 1.8 0.5
ord_722_legetimene_1 1.3 0.1
ord_723_legetimene_500 2.0 0.3
ord_744_allsidighet_200 1.4 0.4
ord_748_fyrstikkeske_200 1.2 -0.5
ord_750_skylde_1 2.2 -0.8
ord_750_skylde_500 3.2 -0.8
sand_188_sand_200 2.3 -0.7

We might also look at this visually, with tracelines.

Removal of poor items and re-estimation of IRT model

We remove the 12 items with difficulty or discrimination less than -4 and 1, respectively. The removed items are

##  [1] "ord_011_sak_500"   "ord_034_lek_1"     "ord_046_fem_1"    
##  [4] "ord_055_les_500"   "ord_085_rop_2"     "ord_157_møte_2"   
##  [7] "ord_170_våte_1"    "ord_178_hjul_1"    "ord_230_brød_1"   
## [10] "ord_258_fyre_1"    "ord_406_skrape_1"  "ord_506_planter_1"

Next, we re-estimate the IRT model. Here are the discriminations vs difficulties:

List of recalibrated IRT pars

a d
ord_001_dag_2 1.6 -1.4
ord_003_dag_500 2.3 -0.8
ord_005_tak_2 2.1 -1.9
ord_006_tak_1 1.8 -2.0
ord_007_tak_500 1.5 -2.3
ord_010_sak_1 1.7 -1.9
ord_012_sak_200 2.7 -0.9
ord_013lam_2 1.9 -1.7
ord_014lam_1 1.2 -1.9
ord_015lam_500 1.6 -2.0
ord_018_rar_1 1.5 -2.0
ord_019_rar_500 2.2 -1.3
ord_020_rar_200 3.6 -0.5
ord_021_far_2 1.6 -2.2
ord_022_far_1 1.5 -2.2
ord_023_far_500 2.7 -1.1
ord_025_lat_2 2.6 -1.4
ord_027_lat_500 2.2 -1.2
ord_028_lat_200 1.8 -0.5
ord_029_hav_2 1.5 -1.7
ord_031_hav_500 1.6 -1.5
ord_035_lek_500 3.3 -1.3
ord_038_mel_1 2.0 -1.6
ord_039_mel_500 1.5 -1.9
ord_042_pen_1 1.8 -1.7
ord_043_pen_500 2.5 -1.4
ord_044_pen_200 1.3 -1.6
ord_047_fem_500 1.0 -2.1
ord_049_ser_2 2.1 -2.1
ord_050_ser_1 1.5 -2.3
ord_051_ser_500 1.7 -1.4
ord_053_les_2 1.9 -2.1
ord_057_fat_2 1.4 -2.0
ord_059_fat_500 2.0 -1.2
ord_060_fat_200 2.0 -0.9
ord_061_fin_2 1.7 -2.3
ord_063_fin_500 1.4 -2.1
ord_067_rir_500 2.3 -1.3
ord_068_rir_200 1.6 -1.1
ord_071_ris_500 1.5 -2.2
ord_072_ris_200 2.5 -1.2
ord_073_lov_2 1.7 -1.9
ord_074_lov_1 1.6 -2.0
ord_075_lov_500 1.4 -2.2
ord_079_bil_500 1.2 -0.7
ord_080_bil_200 1.3 -0.6
ord_082_kos_1 1.7 -1.8
ord_083_kos_500 2.5 -1.3
ord_087_rop_500 4.0 -1.2
ord_088_rop_200 3.3 -0.7
ord_090_hun_1 1.3 -1.8
ord_091_hun_500 2.1 -1.2
ord_092_hun_200 1.4 -1.2
ord_093_bur_2 2.1 -1.1
ord_095_bur_500 2.1 -0.8
ord_096_bur_200 4.1 -0.5
ord_097_dyr_2 1.6 -1.9
ord_098_dyr_1 1.6 -1.8
ord_099_dyr_500 2.2 -1.5
ord_103_sør_500 1.9 -1.3
ord_104_sør_200 3.0 -0.7
ord_105_dør_2 1.3 -2.1
ord_107_dør_500 1.5 -1.3
ord_108_dør_200 1.8 -1.2
ord_111_søl_500 2.2 -1.1
ord_113_bål_2 1.6 -1.6
ord_115_bål_500 2.3 -0.9
ord_116_bål_200 3.8 -0.4
ord_117_bra_2 1.6 -2.0
ord_119_bra_500 2.0 -1.2
ord_120_bra_200 2.8 -1.0
ord_121_arm_2 1.8 -1.9
ord_123_arm_500 2.9 -1.3
ord_124_arm_200 2.9 -0.7
ord_125_sol_2 1.5 -2.2
ord_129_mus_2 1.7 -2.1
ord_131_mus_500 2.5 -1.2
ord_133_bok_2 1.7 -2.2
ord_137_syn_2 1.3 -2.3
ord_139_syn_500 2.9 -1.2
ord_141_dele_2 2.0 -1.5
ord_143_dele_500 3.1 -0.8
ord_144_dele_200 3.8 -0.4
ord_145_lege_2 1.9 -1.6
ord_146_lege_1 1.4 -1.4
ord_147_lege_500 2.6 -1.0
ord_148_lege_200 2.6 -0.5
ord_150_gate_1 2.0 -1.6
ord_151_gate_500 1.9 -1.3
ord_152_gate_200 1.6 -1.1
ord_153_hale_2 1.5 -2.5
ord_154_hale_1 3.7 -0.9
ord_155_hale_500 2.0 -1.4
ord_156_hale_200 2.2 -0.7
ord_159_møte_500 2.3 -0.8
ord_160_møte_200 2.7 -0.5
ord_162_nyse_1 2.1 -1.4
ord_163_nyse_500 3.7 -0.8
ord_164_nyse_200 3.3 -0.5
ord_166_rope_1 1.8 -1.8
ord_169_våte_2 1.4 -2.1
ord_171_våte_500 2.7 -1.0
ord_172_våte_200 1.7 -1.2
ord_174_kino_1 1.7 -1.5
ord_175_kino_500 2.8 -0.9
ord_176_kino_200 2.0 -0.7
ord_179_hjul_500 2.1 -1.3
ord_180_hjul_200 3.4 -0.6
ord_181_peis_2 2.0 -1.6
ord_182_peis_1 1.8 -1.8
ord_183_peis_500 2.3 -1.1
ord_184_peis_200 3.0 -0.7
ord_186_sand_1 1.6 -1.5
ord_187_sand_500 2.9 -1.1
ord_188_sand_200 3.7 -0.5
ord_190_våge_1 2.6 -1.1
ord_191_våge_500 2.3 -0.8
ord_192_våge_200 3.2 -0.3
ord_193_kort_2 1.4 -2.0
ord_193_kort_200 2.8 -0.5
ord_194_kort_1 1.7 -1.4
ord_195_kort_500 3.5 -0.8
ord_198_natt_1 2.3 -1.7
ord_199_natt_500 2.6 -1.3
ord_200_natt_200 2.6 -0.7
ord_202_uret_1 1.5 -1.5
ord_206_leke_1 2.0 -1.4
ord_207_leke_500 1.9 -1.2
ord_208_leke_200 3.2 -0.4
ord_210_høne_1 1.3 -1.8
ord_211_høne_500 2.2 -0.9
ord_212_høne_200 2.8 -0.5
ord_213_tann_2 2.0 -1.8
ord_215_tann_500 1.2 -2.4
ord_216_tann_200 2.5 -0.7
ord_217_lang_2 1.2 -2.1
ord_218_lang_1 3.2 -1.0
ord_219_lang_500 2.4 -0.9
ord_220_lang_200 2.0 -0.7
ord_221_bart_2 1.9 -1.2
ord_223_bart_500 3.2 -0.6
ord_224_bart_200 2.9 -0.2
ord_226_bråk_1 1.4 -1.4
ord_227_bråk_500 2.1 -0.8
ord_228_bråk_200 2.6 -0.5
ord_231_brød_500 2.0 -1.5
ord_232_brød_200 3.7 -0.6
ord_233_hest_2 1.5 -2.0
ord_234_hest_1 1.8 -1.4
ord_235_hest_500 2.8 -1.2
ord_236_hest_200 2.5 -0.8
ord_239_såpe_500 2.1 -1.0
ord_241_bord_2 1.3 -1.8
ord_242_bord_1 1.7 -1.2
ord_243_bord_500 4.4 -0.7
ord_244_bord_200 2.2 -0.7
ord_246_rote_1 1.7 -1.6
ord_247_rote_500 2.1 -1.2
ord_248_rote_200 3.2 -0.7
ord_254_klam_1 1.4 -1.2
ord_255_klam_500 2.2 -0.5
ord_256_klam_200 3.1 -0.2
ord_257_fyre_2 1.4 -1.8
ord_259_fyre_500 2.3 -1.3
ord_260_fyre_200 2.0 -1.0
ord_262_slått_1 1.3 -1.0
ord_263_slått_500 1.8 -0.4
ord_266_frosk_1 1.6 -1.1
ord_267_frosk_500 2.0 -0.6
ord_268_frosk_200 3.6 -0.3
ord_271_sykle_500 2.9 -1.1
ord_272_sykle_200 2.4 -0.6
ord_274_lekser_1 1.1 -1.1
ord_275_lekser_500 1.6 -1.0
ord_278_klokke_1 1.6 -0.7
ord_279_klokke_500 2.3 -0.3
ord_280_klokke_200 3.4 -0.1
ord_282_synge_1 2.3 -1.0
ord_283_synge_500 3.2 -0.5
ord_284_synge_200 3.3 -0.4
ord_287_arver_500 1.6 -0.8
ord_290_skolen_1 1.5 -1.3
ord_295_hunden_500 1.7 0.1
ord_296_hunden_200 2.7 0.2
ord_299_padle_500 2.6 -0.5
ord_300_padle_200 3.4 -0.3
ord_302_esker_1 1.2 -0.9
ord_303_esker_500 1.6 -0.3
ord_304_esker_200 1.6 0.2
ord_307_planke_500 2.0 -0.9
ord_310_niste_1 2.3 -0.8
ord_311_niste_500 2.5 -0.4
ord_312_niste_200 3.1 -0.2
ord_316_bamse_200 2.7 -0.5
ord_318_hjerne_1 2.4 -1.0
ord_319_hjerne_500 2.4 -0.4
ord_320_hjerne_200 2.2 -0.3
ord_323_lappen_500 1.8 -0.8
ord_324_lappen_200 1.4 -0.8
ord_327_spruter_500 2.1 0.6
ord_328_spruter_200 2.4 0.7
ord_330_bukser_1 1.9 -0.9
ord_331_bukser_500 2.6 -0.6
ord_332_bukser_200 2.9 -0.3
ord_335_genser_500 2.3 -0.5
ord_336_genser_200 2.4 -0.2
ord_338_bakke_1 1.7 -1.6
ord_339_bakke_500 2.4 -1.0
ord_340_bakke_200 2.0 -1.0
ord_342_hjelm_1 1.8 -0.5
ord_343_hjelm_500 1.6 -0.2
ord_344_hjelm_200 2.2 0.2
ord_347_bilde_500 1.7 0.2
ord_348_bilde_200 2.3 0.3
ord_351_glade_500 2.4 -0.9
ord_352_glade_200 3.3 -0.5
ord_354_kosten_1 2.1 -1.2
ord_355_kosten_500 1.9 -0.9
ord_356_kosten_200 1.5 -0.7
ord_359_visper_500 1.9 0.1
ord_360_visper_200 2.6 0.5
ord_362_kornet_1 1.4 -0.2
ord_363_kornet_500 1.6 0.2
ord_367_silke_500 1.2 0.0
ord_371_slave_500 2.2 0.0
ord_372_slave_200 2.5 0.3
ord_375_teller_500 2.8 -0.7
ord_376_teller_200 3.0 -0.4
ord_378_brøler_1 1.7 -1.2
ord_379_brøler_500 3.1 -0.5
ord_380_brøler_200 2.9 -0.3
ord_383_gnager_500 1.7 -0.1
ord_384_gnager_200 1.6 0.4
ord_387_eksem_500 1.6 -0.6
ord_390_kloden_1 2.3 -0.5
ord_391_kloden_500 3.0 -0.3
ord_392_kloden_200 3.0 0.1
ord_394_flaske_1 1.1 0.2
ord_395_flaske_500 2.6 0.3
ord_396_flaske_200 1.9 0.6
ord_399_styrke_500 2.1 0.0
ord_400_styrke_200 1.7 0.3
ord_408_skrape_200 1.4 0.8
ord_411_salve_500 1.8 0.2
ord_412_salve_200 1.9 0.5
ord_414_lykten_1 1.5 -1.2
ord_416_lykten_200 1.9 -0.6
ord_420_mynter_200 1.8 -0.8
ord_422_drops_1 1.5 -1.3
ord_423_drops_500 3.3 -0.8
ord_424_drops_200 3.2 -0.4
ord_427_våren_500 1.5 -1.1
ord_428_våren_200 3.1 -0.3
ord_430_dukken_1 1.4 -1.4
ord_431_dukken_500 1.2 -1.1
ord_432_dukken_200 2.0 -0.5
ord_435_sukker_500 3.2 -1.0
ord_436_sukker_200 2.3 -0.8
ord_442_luktet_1 1.2 -0.2
ord_443_luktet_500 1.6 0.0
ord_444_luktet_200 1.9 0.5
ord_451_dusten_500 2.0 -0.6
ord_452_dusten_200 1.6 -0.7
ord_455_skøyter_500 2.9 0.1
ord_456_skøyter_200 2.6 0.2
ord_458_tenker_1 1.8 -1.0
ord_459_tenker_500 4.2 -0.3
ord_460_tenker_200 3.8 -0.1
ord_462_krangle_1 2.1 -0.6
ord_464_krangle_200 3.5 -0.1
ord_467_trasket_500 2.6 0.1
ord_468_trasket_200 2.7 0.3
ord_470_vinduer_1 1.3 -1.0
ord_471_vinduer_500 2.1 -0.7
ord_472_vinduer_200 2.1 -0.2
ord_478_marsjerer_1 1.4 -0.7
ord_479_marsjerer_500 3.3 -0.2
ord_480_marsjerer_200 2.3 0.1
ord_482_kantarell_1 1.5 -1.0
ord_483_kantarell_500 2.0 -0.5
ord_484_kantarell_200 1.9 0.1
ord_486_tallerken_1 1.1 -1.2
ord_494_glitret_1 2.5 -0.5
ord_495_glitret_500 2.6 -0.2
ord_496_glitret_200 2.5 0.1
ord_499_praktisk_500 2.2 0.1
ord_500_praktisk_200 2.4 0.4
ord_503_speilet_500 2.0 -0.7
ord_504_speilet_200 2.8 -0.2
ord_516_kanonen_200 1.8 0.9
ord_519_fantastisk_500 1.4 -0.3
ord_520_fantastisk_200 1.8 -0.1
ord_523_transport_500 2.4 -0.7
ord_524_transport_200 2.0 -0.5
ord_530_prestene_1 1.6 -0.4
ord_531_prestene_500 1.9 0.0
ord_532_prestene_200 2.0 0.4
ord_538_instrument_1 2.4 -0.6
ord_539_instrument_500 2.6 -0.2
ord_540_instrument_200 2.0 -0.1
ord_542_balansere_1 2.6 -0.4
ord_544_balansere_200 2.4 0.4
ord_547_direkte_500 2.6 -0.3
ord_548_direkte_200 3.0 -0.1
ord_554_annerledes_1 2.9 -0.5
ord_555_annerledes_500 2.5 -0.6
ord_556_annerledes_200 2.7 -0.1
ord_559_stativene_500 3.2 -0.1
ord_560_stativene_200 2.1 0.1
ord_563_stranden_500 2.8 -0.3
ord_564_stranden_200 2.7 -0.1
ord_567_skjelett_500 1.0 -0.5
ord_570_strutsene_1 1.5 -0.3
ord_575_spraglete_500 2.3 0.3
ord_576_spraglete_200 1.9 0.6
ord_579_uhøflig_500 3.5 0.0
ord_580_uhøflig_200 2.9 0.2
ord_583_hemmelig_500 2.9 -0.8
ord_584_hemmelig_200 2.7 -0.7
ord_588_slåsskamp_200 1.9 -0.2
ord_591_eksplosjon_500 2.1 0.1
ord_592_eksplosjon_200 2.7 0.4
ord_599_pasning_500 2.6 -0.6
ord_600_pasning_200 2.9 -0.2
ord_606_ordentlig_1 2.4 -1.1
ord_607_ordentlig_500 2.8 -0.7
ord_608_ordentlig_200 2.7 -0.6
ord_611_konsentrasjon_500 2.0 -0.1
ord_612_konsentrasjon_200 1.4 0.0
ord_622_kraftverk_1 3.1 -0.3
ord_623_kraftverk_500 3.1 0.0
ord_624_kraftverk_200 2.1 0.3
ord_626_overraskelsen_1 1.4 -0.8
ord_627_overraskelsen_500 1.4 -0.4
ord_628_overraskelsen_200 1.9 0.2
ord_634_kalenderne_1 2.5 -0.5
ord_638_systemene_1 2.6 -0.6
ord_639_systemene_500 2.8 -0.2
ord_640_systemene_200 2.5 0.1
ord_644_kikkertene_200 1.4 0.7
ord_650_skyskraperen_1 1.3 -0.2
ord_651_skyskraperen_500 1.6 0.3
ord_652_skyskraperen_200 1.5 0.9
ord_654_tørklær_1 1.8 -0.3
ord_655_tørklær_500 2.3 0.2
ord_656_tørklær_200 2.3 0.4
ord_658_forklærne_1 1.6 -0.8
ord_659_forklærne_500 2.8 -0.4
ord_660_forklærne_200 1.8 -0.1
ord_670_kvalmende_1 1.8 -0.6
ord_671_kvalmende_500 3.1 0.0
ord_672_kvalmende_200 2.9 0.2
ord_690_alarmanlegg_1 1.4 -0.7
ord_692_alarmanlegg_200 1.9 0.3
ord_699_avslappende_500 1.8 -0.7
ord_700_avslappende_200 1.8 -0.5
ord_708_kontraktene_200 1.3 1.2
ord_710_forvekslinger_1 1.4 0.2
ord_712_forvekslinger_200 1.8 0.5
ord_722_legetimene_1 1.3 0.1
ord_723_legetimene_500 2.0 0.3
ord_744_allsidighet_200 1.4 0.4
ord_748_fyrstikkeske_200 1.2 -0.5
ord_750_skylde_1 2.2 -0.8
ord_750_skylde_500 3.2 -0.8
sand_188_sand_200 2.3 -0.7

We might also look at the new estimates with tracelines.