The Treasury

Global Navigation

Personal tools

Appendix (continued)

Table A.3 – Models for singles and sole parents with alternative fixed cost of working
  Single men Single women Sole parents
  Estimated coefficient z-valueb Estimated coefficient z-valueb Estimated coefficient z-valueb
  Estimated coefficient z-valueb Estimated coefficient z-valueb Estimated coefficient z-valueb
  Single men Single women Sole parents
Quadratic terms            
Income 100,000 -0.1241 -3.55 -0.2948 -4.96 -0.0505 -1.66
Labour supply × 100 -0.8778 -12.02 -0.6814 -11.81 -0.2794 -4.74
Cross product            
Inc. & lab. sup. × 10,000 -1.6333 -9.73 -1.8331 -8.67 -0.5342 -2.69
Linear terms            
Income × 100            
constant 0.9509 7.42 1.5547 9.62 0.5902 2.97
Youngest child <1 yr         0.1221 1.92
Youngest child 1-3 yrs old         0.0514 1.70
Youngest child 4-5 yrs old         0.0030 0.13
Youngest child 6-9 yrs old         -0.0201 -1.17
Number of children         0.0138 1.60
Age/10 0.1430 2.67 0.0568 0.76 -0.0973 -1.61
Age squared/100 -0.0118 -1.61 -0.0052 -0.54 0.0120 1.55
Vocational education -0.0469 -1.74 -0.0204 -0.49 -0.0570 -2.33
Certificate -0.0542 -2.14 -0.0324 -0.80 -0.0516 -2.33
Bursary/scholarship -0.1022 -3.83 -0.0883 -2.08 -0.0102 -0.44
Postgraduate degree/other -0.1611 -2.99 0.0758 0.90 -0.0177 -0.45
Bachelor degree -0.0423 -1.13 0.1971 3.19 0.0602 1.59
Postgraduate 0.0528 0.83 0.3318 3.31 0.0487 0.92
Live with parents 0.0352 4.38 0.0682 3.20    
female         -0.1629 -3.71
Labour supply            
constant 0.4866 9.07 0.3600 8.65 0.2089 2.83
Youngest child <1 yr         -0.0117 -0.43
Youngest child 1-3 yrs old         -0.0213 -1.72
Youngest child 4-5 yrs old         -0.0398 -3.39
Youngest child 6-9 yrs old         -0.0357 -4.18
Number of children         0.0025 0.61
Age/10 0.0487 3.44 0.0336 3.39 -0.0071 -0.22
Age squared/100 -0.0056 -2.91 -0.0053 -4.12 0.0005 0.12
Vocational education 0.0109 1.59 0.0236 4.45 0.0117 1.37
Certificate 0.0052 0.79 0.0167 3.26 -0.0068 -0.73
Bursary/scholarship -0.0100 -1.46 0.0190 3.57 0.0283 2.50
Postgraduate degree/other -0.0220 -1.61 0.0317 3.28 0.0317 1.69
Bachelor degree 0.0020 0.21 0.0453 6.06 0.0702 4.74
Postgraduate 0.0206 1.39 0.0586 4.79 0.0610 2.55
female         -0.0836 -5.22
Time trend 0.0000 -0.03 -0.0001 -0.19 0.0018 1.84
Unemployment rate -0.0013 -1.78 -0.0011 -0.99 0.0003 0.21
Aged over 60 -0.0153 -1.82 -0.0204 -2.37 -0.0261 -0.46
Eligible for NZ superannuation -0.0339 -2.51 -0.0259 -2.37 -0.1545 -2.09
Live with parents         0.0085 1.28
Fixed costs/100            
0-10 hours 7.5338 12.98 4.1489 12.91 13.4319 3.19
11-20 hours 11.2123 12.04 5.8588 11.78 17.7789 3.16
21-30 hours 14.1347 12.22 7.1534 11.54 21.3914 3.09
>30 hours 13.7870 11.56 6.8353 10.58 20.2658 3.00
Unobserved heterogeneity            
Variance income 0.0000 0.25 0.0000 0.16 0.0000 0.06
Variance labour supply 0.0000 0.33 0.0000 0.77 0.0000 0.19
Variance fixed cost 0.0021 0.42 0.0010 0.78 0.0078 0.52
Covariance inc. & labour supply 0.0000 0.29 0.0000 0.20 0.0000 0.09
Covariance inc. & fixed cost -0.0001 -0.25 -0.0001 -0.20 0.0000 -0.05
Covariance lab.sup. & fixed cost 0.0000 -0.31 0.0000 0.54 0.0000 -0.04
Log likelihood -7434   -7093   -2775  
  1. Eleven discrete points of labour supply are distinguished for each person: 0 hours for non-participants and people working less than 2.5 hours, 5 hours for people working from 2.5 to 7.5 hours, 10 hours for people working from 7.5 to 12.5 hours, 15 hours for people working from 12.5 to 17.5 hours, 20 hours for people working from 17.5 to 22.5 hours, 25 hours for people working from 22.5 to 27.5 hours, 30 hours for people working from 27.5 to 32.5 hours, 35 hours for people working from 32.5 to 37.5 hours, 40 hours for people working from 37.5 to 42.5 hours, 45 hours for people working from 42.5 to 47.5 hours, and 50 hours for people working more than 47.5 hours.
  2. The z-value indicates the level of significance of the estimated coefficients. A value of 1.96 or more means that the parameter is significantly different from zero at the 5% level at least. The higher the z-value the more precise the estimated coefficient.
  3. For sole parents people with a degree are categorized in a group with those having a diploma, because of the limited number of observations on sole parents with a higher level of education.
Page top