Who are those random responders on your survey? The case of the TIMSS 2015 student questionnaire

Large-scale Assessments in Education

An IERI – International Educational Research Institute Journal

Table 1 Percentage of fourth-grade students in each of covariates’ categories

Educational system	Gender: female	Gender: male	SES: 0–10 books	SES: 11–25 books	SES: 26–100 books	SES: 101–200 books	SES: > 200 books	SES: missing	Language: never/sometimes	Language: (almost) always	Language: missing	Migration: native-born parents	Migration: foreign-born parent	Migration: missing	Sample Size: n
ARE	48	52	19	30	27	10	9	4	45	52	4	25	61	15	21177
AUS	49	51	8	18	35	21	16	1	15	84	2	52	37	11	6057
BHR	50	50	20	29	25	11	11	3	31	66	3	52	36	12	4146
CAN	49	51	10	21	38	17	13	2	24	74	2	45	42	12	12283
CHL	49	51	31	33	22	6	5	3	10	87	3	84	8	8	4756
ENG	51	49	10	22	34	18	14	3	17	81	2	52	34	13	4006
HKG	46	54	14	20	32	18	16	1	29	70	1	36	47	17	3600
IRN	49	51	40	27	18	6	6	2	33	65	2	78	12	10	3823
IRL	47	53	9	20	33	20	16	1	12	83	5	69	26	5	4344
ITA	49	51	17	35	28	10	8	1	16	83	1	75	21	4	4373
JPN	50	50	12	29	37	13	8	0	2	98	0	94	3	3	4383
KOR	48	52	4	4	18	29	44	0	8	92	0	96	2	2	4669
KWT	51	49	28	31	17	7	6	10	65	25	10	50	30	20	3593
NZL	49	51	11	19	33	19	17	2	16	83	1	47	40	13	6322
NOR	49	51	7	22	38	19	12	2	15	84	1	70	27	4	4329
OMN	50	50	28	28	23	9	10	4	36	60	4	71	19	11	9105
QAT	51	49	20	28	27	11	11	3	46	52	1	30	56	14	5194
SAU	49	51	32	27	17	7	8	9	19	74	7	66	16	18	4337
SGP	48	52	10	21	37	18	13	0	51	49	0	47	44	9	6517
TUR	49	51	22	33	28	8	5	4	15	80	5	84	7	8	6456
TWN	49	51	19	25	29	13	13	0	40	59	1	65	13	22	4291
USA	51	49	13	23	33	15	13	3	20	76	3	51	27	22	10029