Skip to main content

Table 6 Alternative measures of the “income/wealth” component of socio-economic status

From: The measure of socio-economic status in PISA: a review and some suggested improvements

 Original measure (HOMEPOS)Alternative 1 (HOMEPOS1)Alternative (HOMEPOS2)
National item parameters (all countries)Classic literature, books of poetry, national ST011 itemsClassic literature, books of poetryClassic literature, books of poetry, works of art, cars, rooms with a bath or shower, musical instruments, educational software
National item parameters (select countries)Educational software (JPN)aEducational software (JPN)a 
Supplementary items National ST011 itemsNational ST011 items
Validity (country-level evidence)
 Pearson correlation between mean index and country GNI per capita0.650.650.64
 Pearson correlation between share of students below a low threshold and WB absolute poverty rate (% of the population living on less than $5.50 a day)0.850.850.84
Student-level comparisons with original
 Number of non-missing observations468,671468,783468,169
 Number of missing observations818180698683
 OECD mean− 0.010.000.00
 OECD standard deviation1.001.001.00
 Range (min; max)− 9.5; 6.0− 8.8; 6.1− 24.1; 9.3
 Correlation with original measure in database1.001.000.98
Country-level comparisons with original
 Country means
  Pearson correlation with original1.001.000.98
  Spearman correlation with original1.001.000.97
  Mean absolute deviation with original0.000.050.18
Max positive deviation and country0.000.24 (Indonesia)0.64 (Indonesia)
  Min negative deviation and country0.00− 0.06 (Qatar)− 0.30 (United States)
 Relationship with science performance (R2)
  OECD average0.0810.0860.093
  Pearson correlation with original1.001.000.99
  Spearman correlation with original1.001.000.99
  Mean absolute deviation with original0.000.000.01
  Max positive deviation and country0.000.01 (Hungary)0.04 (France)
  Min negative deviation and country0.00− 0.01 (Belgium)0.00 (Spain)
 Relationship with science performance (beta)
  OECD average31.231.131.2
  Pearson correlation with original1.000.990.96
  Spearman correlation with original1.000.990.95
  Mean absolute deviation with original0.001.22.5
  Max positive deviation and country0.002.5 (Indonesia)6.3 (Peru)
  Min negative deviation and country0.00− 3.3 (Belgium)− 7.0 (Denmark)
  1. A comparison based on PISA 2015 data (Public use files, excluding Albania, Spanish regions’ sample, Massachusetts, North Carolina, Puerto Rico)
  2. Alternative 1 differs from the original variable in the database due to the use of a different scaling software [R package TAM; (Robitzsch et al. 2019)] and of a different calibration sample (in particular, different weights for Belgium and the United Kingdom, and different observations for Spain)
  3. a Also one item for Puerto Rico and one item for Albania