Index of Real Wages from 2003 to 2014

APPENDIX A

Table 1A. Summary statistics for those who work more than 20 hours (All observations)
Males (N=3375) / Females (N=3620) / Overall (N=6995)
Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within / Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within / Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within
Sleep duration / 6.900 / .917 / .889 / .333 / 7.046 / .920 / .883 / .366 / 6.976 / .922 / .890 / .351
Sleep difficulties / .208 / .406 / .385 / .186 / .319 / .466 / .438 / .210 / .265 / .442 / .417 / .199
Sleep medicine / .067 / .249 / .241 / .105 / .107 / .310 / .296 / .131 / .088 / .283 / .272 / .119
ln (Real wages) / .830 / .461 / .454 / .162 / .643 / .486 / .469 / .186 / .733 / .483 / .471 / .175
Female / .518 / .500 / .500
Age / 46.951 / 12.793 / 13.365 / 1.454 / 44.719 / 11.971 / 12.385 / 1.423 / 45.795 / 12.424 / 12.897 / 1.438
Urban area (>5000 residents) / .660 / .474 / .466 / .097 / .685 / .465 / .457 / .108 / .673 / .469 / .461 / .103
Urban area (1000-4999 residents) / .195 / .396 / .384 / .095 / .178 / .382 / .374 / .096 / .186 / .389 / .379 / .096
Urban area (200-999 residents) / .071 / .258 / .243 / .080 / .061 / .240 / .242 / .069 / .066 / .249 / .243 / .074
Rural area (<200 residents) / .074 / .262 / .263 / .062 / .076 / .265 / .256 / .063 / .075 / .264 / .260 / .062
Single / .085 / .279 / .289 / .068 / .106 / .308 / .303 / .080 / .096 / .295 / .296 / .074
Steady / .040 / .197 / .211 / .074 / .044 / .205 / .199 / .092 / .042 / .201 / .204 / .084
Cohabiting / .187 / .390 / .383 / .128 / .191 / .393 / .385 / .122 / .189 / .392 / .384 / .125
Divorced / .036 / .186 / .184 / .070 / .070 / .25 / .240 / .090 / .053 / .225 / .216 / .081
Widowed / .004 / .067 / .072 / .019 / .019 / .135 / .140 / .028 / .012 / .108 / .113 / .024
Married / .647 / .478 / .478 / .117 / .570 / .495 / .490 / .100 / .607 / .488 / .485 / .109
Child under four / .143 / .350 / .340 / .150 / .140 / .347 / .325 / .160 / .142 / .349 / .332 / .155
Household size / 3.066 / 1.490 / 1.436 / .538 / 3.012 / 1.451 / 1.399 / .490 / 3.038 / 1.470 / 1.416 / .513
Junior high school / .200 / .400 / .416 / .264 / .441 / .447 / .233 / .423 / .433
Vocational education / .454 / .498 / .497 / .276 / .447 / .449 / .362 / .481 / .480
Bachelor or technical degree / .204 / .403 / .400 / .327 / .469 / .466 / .268 / .443 / .440
Master or doctoral degree / .142 / .349 / .336 / .134 / .341 / .330 / .138 / .345 / .333
Year07 / .374 / .484 / .397 / .358 / .353 / .478 / .395 / .346 / .363 / .481 / .396 / .352
Year09 / .240 / .427 / .263 / .356 / .244 / .430 / .271 / .352 / .242 / .429 / .267 / .354
Year12 / .385 / .487 / .430 / .325 / .403 / .491 / .431 / .324 / .395 / .489 / .431 / .324
Pooled OLS
Male (N=3375) / Female (N=3620) / Total (N=6995)
Sleep difficulties / -.294
(.227) / -.528***
(.173) / -.372***
(.143)
Sleep medicine / .659
(.586) / -.086
(.618) / .341
(.424)
Age*sleep difficulties / -.003
(.005) / .002
(.004) / -.001
(.003)
Age*sleep medicine / -.014
(.011) / .0008
(.012) / -.008
(.008)
Sleep difficulties* sleep medicine / -3.534**
(1.573) / .055
(1.891) / -1.376
(1.275)
Age*sleep medicine*sleep difficulties / .111*
(.060) / -.021
(.076) / .0031
(.050)
Age squared*sleep medicine* sleep difficulties / -.0008
(.0006) / .0003
(.0008) / -.0001
(.0005)
ln(Real wages) / .068
(.052) / .031
(.042) / .041
(.034)
Female / .216***
(.031)
Age / .024*
(.012) / -.013
(.012) / .004
(.009)
Age squared / -.0002
(.0001) / .00004
(.0001) / -.00007
(.0001)
Urban area (1000-4999 residents) / -.026
(.056) / .005
(.052) / -.023
(.039)
Urban area (200-999 residents) / -.173**
(.082) / .205***
(.077) / -.003
(.061)
Rural area (< 200 residents) / -.007
(.112) / .157**
(.072) / .066
(.067)
Single / .056
(.091) / -.146**
(.075) / -.057
(.060)
Steady / .061
(.114) / -.046
(.097) / -.028
(.075)
Cohabiting / .052
(.053) / .003
(.051) / .026
(.038)
Divorced / -.188*
(.112) / -.223***
(.073) / -.240***
(.062)
Widowed / -.010
(.306) / -.005
(.149) / -.054
(.132)
Child under four / -.132**
(.056) / -.218***
(.052) / -.169***
(.039)
Household size / -.029*
(.016) / -.051***
(.017) / -.039***
(.011)
Vocational education / .031
(.065) / .032
(.058) / .039
(.044)
Bachelor or technical degree / .141**
(.070) / .083
(.056) / .117***
(.045)
Master or doctoral degree / .072
(.077) / .047
(.069) / .076
(.052)
Year09 / .130***
(.041) / .057
(.037) / .092***
(.028)
Year12 / .078**
(.038) / .004
(.035) / .041
(.026)
Constant / 6.354***
(.284) / 7.828***
(.259) / 6.982***
(.193)
R2: / .066 / .086 / .072
*** p < .01, ** p < .05, * p < .10. Benchmark for marital status is married; for residential area an area with > 5,000 residents; high school or less for education; and 2007 for year.
Standard errors are presented in parentheses in the FE analysis. Linearized, robust standard errors are presented in parentheses in the OLS analysis.
Results from the fixed-effects analysis are not presented here as the method cannot include subjects who have answered only one wave of the data.

APPENDIX B

Table 1B. Summary statistics for those who work more than 20 hours and answered all three waves of the data.
Males (N=1251) / Females (N=1158) / Overall (N=2409)
Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within / Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within / Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within
Sleep duration / 6.958 / .894 / .780 / .439 / 7.024 / .913 / .764 / .501 / 6.990 / .904 / .773 / .470
Sleep difficulties / .193 / .395 / .307 / .249 / .307 / .462 / .354 / .297 / .248 / .432 / .335 / .273
Sleep medicine / .064 / .245 / .197 / .146 / .100 / .300 / .241 / .180 / .081 / .273 / .220 / .163
ln(Real wages) / .895 / .408 / .352 / .207 / .707 / .469 / .398 / .248 / .805 / .448 / .386 / .228
Female / .481 / .500 / .500
Age / 47.367 / 10.763 / 10.573 / 2.056 / 45.121 / 10.291 / 10.093 / 2.056 / 46.287 / 10.596 / 10.399 / 2.055
Urban area (>5000 residents) / .657 / .475 / .456 / .133 / .686 / .464 / .441 / .148 / .671 / .470 / .449 / .140
Urban area (1000-4999 residents) / .197 / .398 / .378 / .126 / .173 / .378 / .355 / .131 / .186 / .389 / .367 / .129
Urban area (200-999 residents) / .082 / .274 / .251 / .111 / .056 / .230 / .205 / .105 / .069 / .254 / .230 / .108
Rural area (<200 residents) / .064 / .245 / .229 / .086 / .085 / .280 / .265 / .090 / .074 / .262 / .247 / .088
Single / .066 / .249 / .229 / .098 / .107 / .309 / .291 / .105 / .086 / .280 / .262 / .101
Steady / .017 / .129 / .098 / .083 / .032 / .176 / .122 / .127 / .024 / .153 / .110 / .107
Cohabiting / .168 / .374 / .328 / .180 / .190 / .392 / .355 / .168 / .178 / .383 / .341 / .175
Divorced / .030 / .172 / .141 / .098 / .076 / .265 / .232 / .129 / .052 / .223 / .191 / .114
Widowed / .001 / .028 / .016 / .023 / .009 / .097 / .091 / .034 / .005 / .070 / .064 / .029
Married / .718 / .450 / .419 / .167 / .585 / .493 / .474 / .138 / .654 / .476 / .450 / .153
Child under four / .130 / .337 / .259 / .215 / .130 / .337 / .253 / .223 / .130 / .337 / .256 / .219
Household size / 3.203 / 1.505 / 1.312 / .740 / 3.079 / 1.452 / 1.277 / .693 / 3.144 / 1.481 / 1.296 / .718
Junior high school / .137 / .344 / .344 / .225 / .418 / .418 / .179 / .384 / .384
Vocational education / .453 / .498 / .498 / .244 / .429 / .429 / .352 / .478 / .478
Bachelor or technical degree / .228 / .420 / .420 / .355 / .4790 / .479 / .289 / .453 / .453
Master or doctoral degree / .182 / .386 / .386 / .176 / .381 / .381 / .179 / .384 / .384
Year07 / .3333 / .4716 / .4716 / .3333 / .4716 / .4716 / .3333 / .4715 / .4715
Year09 / .3333 / .4716 / .4716 / .3333 / .4716 / .4716 / .3333 / .4715 / .4715
Year12 / .3333 / .4716 / .4716 / .3333 / .4716 / .4716 / .3333 / .4715 / .4715
Table 2B. Fixed-effects and pooled OLS estimations for those who work more than 20 hours per week and answered all three waves of the data
FE / Pooled OLS
Male (N=1251) / Female (N=1158) / Total (N=2409) / Male (N=1251) / Female (N=1158) / Total (N=2409)
Sleep difficulties / -.089
(.303) / -.041
(.277) / -.113
(.199) / -1.369***
(.463) / -.459
(.347) / -.678**
(.318)
Sleep medicine / -.580
(.700) / . 386 (.806) / -.255
(.520) / -.121
(.397) / 1.321
(1.267) / .315
(.610)
Age*sleep difficulties / -.002
(.006) / -.004
(.006) / -.002
(.004) / .016
(.010) / .002
(.008) / .004
(.007)
Age*sleep medicine / .010
(.014) / -.013
(.016) / .002
(.010) / .002
(.011) / -.029
(.025) / -.008
(.013)
Sleep difficulties* sleep medicine / -.999
(2.286) / -1.872
(1.935) / -1.599
(1.391) / -3.717
(3.303) / -1.962
(3.420) / -1.776
(2.474)
Age*sleep medicine*sleep difficulties / . 033
(.089) / .029
(.081) / .042
(.055) / .139
(.134) / -.012
(.137) / .026
(.102)
Age squared*sleep medicine* sleep difficulties / -.0003
(.0009) / .0001
(.0009) / -.0002
(.0006) / -.001
(.001) / .0009
(.001) / .0001
(.001)
ln(Real wages) / .0005
(.079) / .027
(.073) / .017
(.053) / .109
(.106) / .088
(.080) / .095
(.071)
Female / .185***
(.059)
Age / .046
(.029) / -.003
(.034) / .024
(.023)
Age squared / -.0002
(.0004) / .0004
(.0004) / -.00002
(.0003) / -.0004
(.0003) / -.00008
(.0004) / -.0002
(.0003)
Urban area (1000-4999 residents) / -.057
(.130) / -.298**
(.146) / -.180*
(.097) / .072
(.092) / -.128
(.102) / -.031
(.071)
Urban area (200-999 residents) / -.038
(.160) / -.150
(.186) / -.093
(.120) / -.253**
(.115) / .221
(.147) / -.080
(.097)
Rural area (< 200 residents) / -.270
(.200) / -.309
(.209) / -.345**
(.141) / -.279
(.240) / .287**
(.139) / .016
(.152)
Single / -.325*
(.181) / -.174
(.225) / -.255*
(.140) / .181
(.167) / -.285*
(.147) / -.018
(.116)
Steady / .093
(.204) / -.154
(.194) / -.070
(.132) / -.0358
(.297) / -.381***
(.145) / -.310*
(.165)
Cohabiting / .011
(.099) / -.239*
(.142) / -.104
(.082) / .033
(.086) / -.040
(.093) / .018
(.066)
Divorced / -.431**
(.173) / -.008
(.172) / -.173
(.118) / -.501***
(.167) / -.251
(.160) / -.341***
(.118)
Widowed / -.111
(.678) / -.134
(.533) / -.018
(.407) / -.643**
(.326) / -.120
(.494) / -.200
(.504)
Child under four / -.136*
(.072) / -.271***
(.081) / -.198***
(.054) / .079
(.099) / -.184*
(.096) / -.038
(.071)
Household size / .003
(.022) / -.050*
(.027) / -.016
(.017) / -.037
(.026) / -.092***
(.036) / -.045**
(.022)
Vocational education / .038
(.140) / .282**
(.124) / .144
(.098)
Bachelor or technical degree / .079
(.146) / .180
(.119) / .136
(.099)
Master or doctoral degree / -.056
(.151) / .181
(.140) / .074
(.108)
Year09 / .115
(.077) / -.003
(.091) / .075
(.058) / .079**
(.048) / .075
(.049) / .078**
(.035)
Year12 / .097
(.176) / -.182
(.207) / -.007
(.133) / -.003
(.055) / .034
(.055) / .013
(.038)
Constant / 7.554***
(.795) / 6.747***
(.878) / 7.258***
(.582) / 5.837***
(.643) / 7.561***
(.749) / 6.414***
(.511)
R2: / Within: .045
Between: .0001
Overall: .002 / Within: .079
Between: .005
Overall: .011 / Within: .049
Between: .051
Overall: .051 / .152 / .134 / .109
*** p < .01, ** p < .05, * p < .10. Benchmark for marital status is married; for residential area an area with > 5,000 residents; high school or less for education; and 2007 for year.
Standard errors are presented in parentheses in the FE analysis. Linearized, robust standard errors are presented in parentheses in the OLS analysis.

APPENDIX C

Table 1C. Summary statistics for those who answered at least two waves of the data (without work hour restriction)
Males (N=2233) / Females (N=2545) / Overall (N=4778)
Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within / Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within / Mean / St.Dev. Overall / St.Dev. Betw. / St.Dev. Within
Sleep duration / 6.936 / .904 / .788 / .448 / 7.070 / .932 / .801 / .488 / 7.008 / .921 / .798 / .470
Sleep difficulties / .197 / .398 / .318 / .243 / .310 / .463 / .377 / .274 / .257 / .437 / .356 / .260
Sleep medicine / .061 / .239 / .199 / .133 / .111 / .314 / .271 / .167 / .088 / .283 / .242 / .152
ln(Real wages) / .955 / .624 / .522 / .370 / .790 / .668 / .536 / .414 / .867 / .653 / .536 / .394
Female / .533 / .499 / .499
Age / 48.087 / 12.487 / 12.550 / 1.878 / 45.033 / 11.910 / 11.965 / 1.860 / 46.460 / 12.277 / 12.336 / 1.868
Urban area (>5000 residents) / .648 / .478 / .464 / .123 / .683 / .465 / .443 / .142 / .666 / .472 / .453 / .133
Urban area (1000-4999 residents) / .200 / .400 / .383 / .124 / .175 / .380 / .359 / .127 / .187 / .390 / .371 / .126
Urban area (200-999 residents) / .076 / .265 / .246 / .100 / .057 / .232 / .212 / .090 / .066 / .248 / .228 / .095
Rural area (<200 residents) / .077 / .266 / .260 / .080 / .085 / .279 / .265 / .079 / .081 / .273 / .263 / .079
Single / .080 / .271 / .251 / .105 / .106 / .309 / .288 / .112 / .094 / .292 / .272 / .109
Steady / .032 / .177 / .145 / .110 / .045 / .208 / .170 / .127 / .039 / .194 / .159 / .119
Cohabiting / .168 / .374 / .338 / .167 / .193 / .394 / .358 / .161 / .181 / .385 / .349 / .164
Divorced / .034 / .183 / .160 / .091 / .068 / .252 / .226 / .112 / .053 / .223 / .199 / .103
Widowed / .004 / .067 / .065 / .032 / .019 / .137 / .137 / .041 / .012 / .110 / .110 / .037
Married / .681 / .466 / .446 / .148 / .568 / .495 / .479 / .130 / .621 / .485 / .467 / .138
Child under four / .122 / .328 / .271 / .190 / .133 / .340 / .275 / .204 / .128 / .334 / .273 / .197
Household size / 3.056 / 1.488 / 1.297 / .723 / 2.991 / 1.455 / 1.298 / .663 / 3.022 / 1.471 / 1.298 / .692
Junior high school / .163 / .370 / .377 / .256 / .436 / .439 / .213 / .409 / .414
Vocational education / .473 / .499 / .500 / .272 / .445 / .448 / .366 / .482 / .483
Bachelor or technical degree / .214 / .410 / .407 / .332 / .471 / .470 / .277 / .447 / .446
Master or doctoral degree / .150 / .357 / .349 / .140 / .347 / .340 / .145 / .352 / .344
Year07 / .360 / .480 / .138 / .464 / .349 / .477 / .159 / .455 / .354 / .478 / .150 / .459
Year09 / .356 / .479 / .142 / .462 / .360 / .480 / .150 / .461 / .358 / .480 / .146 / .461
Year12 / .283 / .451 / .180 / .421 / .291 / .454 / .187 / .422 / .288 / .453 / .184 / .421
Table 2C. Fixed-effects and pooled OLS estimations for those who answered at least two waves of the data (without work hour restriction)
FE / Pooled OLS
Male (N=2233) / Female (N=2545) / Total (N=4778) / Male (N=2233) / Female (N=2545) / Total (N=4778)
Sleep difficulties / -.431*
(.210) / -.3153*
(.191) / -.384***
(.140) / -.639**
(.298) / -.553**
(.221) / -.549***
(.182)
Sleep medicine / .143
(.622) / .148 (.534) / .042
(.396) / -.134
(.299) / .465
(.781) / .201
(.446)
Age*sleep difficulties / .005
(.004) / .002
(.004) / .004
(.003) / .003
(.006) / .002
(.005) / .001
(.004)
Age*sleep medicine / -.005
(.011) / -.007
(.010) / -.004
(.008) / .0003
(.007) / -.009
(.015) / -.005
(.009)
Sleep difficulties* sleep medicine / -.985
(2.020) / -.034
(1.219) / -.406
(1.001) / -3.834*
(2.189) / -1.003
(2.225) / -1.526
(1.683)
Age*sleep medicine*sleep difficulties / .023
(.075) / -.038
(.047) / -.010
(.038) / .140*
(.082) / -.011
(.086) / .030
(.065)
Age squared*sleep medicine* sleep difficulties / -.00006
(.0007) / .0007
(.0005) / .0003
(.0004) / -.001
(.0008) / .0005
(.0008) / -.00003
(.0006)
ln(Real wages) / .106**
(.033) / .014
(.030) / .051**
(.022) / .115**
(.045) / .051
(.035) / .079***
(.029)
Female / .214***
(.039)
Age / .031**
(.015) / -.009
(.015) / .005
(.011)
Age squared / -.00006
(.0003) / .0004
(.0003) / .0002
(.0002) / -.0003*
(.0002) / -.00006
(.0002) / -.0001
(.0001)
Urban area (1000-4999 residents) / -.120
(.109) / .032
(.100) / -.049
(.073) / -.034
(.076) / .013
(.071) / -.025
(.053)
Urban area (200-999 residents) / -.051
(.140) / -.118
(.145) / -.082
(.100) / -.247***
(.096) / .212*
(.117) / -.043
(.082)
Rural area (< 200 residents) / .005
(.169) / -.250
(.163) / -.154
(.117) / .007
(.158) / .157*
(.085) / .072
(.090)
Single / -.198
(.147) / -.156
(.154) / -.185*
(.106) / .118
(.117) / -.228**
(.091) / -.062
(.074)
Steady / .020
(.140) / -.088
(.141) / -.051
(.098) / .201
(.174) / -.147
(.109) / -.008
(.102)
Cohabiting / .044
(.089) / -.023
(.106) / -.0005
(.069) / .032
(.068) / -.050
(.066) / -.007
(.048)
Divorced / -.318**
(.147) / .061
(.134) / -.092
(.097) / -.338**
(.156) / -.144
(.103) / -.224***
(.087)
Widowed / -.585
(.378) / .231
(.305) / -.040
(.234) / -.410
(.303) / -.076
(.166) / -.191
(.147)
Child under four / -.175**
(.065) / -.245***
(.062) / -.207***
(.045) / -.157**
(.077) / -.262***
(.066) / -.205***
(.051)
Household size / .027
(.018) / -.032*
(.019) / .0004
(.013) / -.018
(.022) / -.058***
(.021) / -.032**
(.015)
Vocational education / -.018
(.093) / .096
(.075) / .037
(.060)
Bachelor or technical degree / .135
(.097) / .127*
(.074) / .127**
(.060)
Master or doctoral degree / .025
(.103) / .050
(.085) / .053
(.067)
Year09 / .120
(.060) / -.050
(.061) / .026
(.042) / .119***
(.040) / .025
(.037) / .071***
(.027)
Year12 / .055
(.137) / -.243*
(.139) / -.119
(.096) / .107***
(.041) / -.006
(.042) / .049
(.0295)
Constant / 6.953***
(.623) / 6.606***
(.594) / 6.680***
(.425) / 6.222***
(.367) / 7.871***
(.323) / 7.030***
(.245)
R2: / Within: .049
Between: .031
Overall: .039 / Within: .056
Between: .001
Overall: .000 / Within: .041
Between: .002
Overall: .006 / .093 / .110 / .091

*** p < .01, ** p < .05, * p < .10. Benchmark for marital status is married; for residential area an area with > 5,000 residents; high school or less for education; and 2007 for year.
Standard errors are presented in parentheses in the FE analysis. Linearized, robust standard errors are presented in parentheses in the OLS analysis.

APPENDIX D

Index of real wages from 2003 to 2014

Source: Statistics Iceland