The Interaction Eﬀects of Disability Typesand Gender on Employment
Assessing Intersectionality in the 2011 Irish
CensusKenjiro Sakakibara
Department of Advanced Social and International Studies,
Graduate School of Arts and Sciences, University of Tokyo
East Asia Disability Studies Forum 2019

Outline

The concept of intersectionality
Additivity and interaction
Modeling intersectionality
Results (1): intersectionality in employment
opportunity
Results (2): intersectionality in occupation

1 / 30Disability and gender
Article 6 of the CRPD: “. . .women and girls withdisabilities are subject to multiple
discrimination. . .”[1]Multiple disadvantage for women with disabilities issuggested in the context of employment[2]· · · Women with disabilities are less likely to beemployed and more likely to be inactive than men
with disabilities

2 / 30Intersectionality[3][4]Multiple inequalities crossing with each other:gender, disability, ethnicity etc.
Possibility of additional disadvantage↔the relation can be complicatedExample [4]A woman with disability was not forced into being ahomemaker, got an education in oﬃce work andbecame self-suﬃcient3 / 30RQ: additivity or interaction?
Two types of intersectionality can be distinguished:
Additivity : simple synthesis of diﬀerent formsof disadvantage
Interaction : more complicated eﬀect (positiveor negative) caused by the intersection of
diﬀerent forms of disadvantage
Research QuestionWhich form of intersectionality applies to the employment disadvantage for women with disabilities?

· · · Considering disability types



4 / 30Statistical eﬀects
The tendency of something to increase/decrease
another thing
Example Suppose men are taller than women onaverage=The eﬀect of gender on height (βG )Statistical model:
X = µ + βG + ϵ(X: height, µ: female average, ϵ: error)
5 / 30Additivity and interaction

βA , βB : The eﬀects of A and B on the outcome X
Additivity X = µ + βA + βB + ϵ(Simple synthesis of two eﬀects)
Interaction X = µ + βA + βB + βAB + ϵ(Diﬀerent from the simple synthesis)
βAB : the interaction term

6 / 30Probability modeling
Estimates the eﬀect of something on the probabilityof an event
Example The probability of being employedf (p) = µ + βG + βD + ϵ(additive model)
f (p) = µ + βG + βD + βGD + ϵ(interaction model)(p: probability, G: gender, D: disability)
pLogit models f (p) = logit(p) = log 1−p· · · Logit corresponds to log-odds

7 / 30Odds and log-odds
pOdds 1−p· · · The ratio of the probabilities that an event
occurs or not
Log-odds The logarithm of the odds

Odds ratio (OR) The ratio of odds with andwithout a condition
e.g. 1 wins : 1 losses →2 wins : 1 losses· · · Odds ratio = 28 / 30

Additive/multiplicative

β’s in a logit model exponentiated = OR
The eﬀect of both A and B: βA + βB
The OR: eβA +βB = eβA eβB · · · The OR of A and B
multiplied
Additive model of log-odds=Multiplicative model of odds ratio

9 / 30Modeling employment
Women and disabled people may be less likely to beemployed=The βG and βD below are asuumed to be negativelogit(pW orking ) = µ + βG + βD [+βGD ] + . . . + ϵ
The OR for Women with disabilities:
eβG +βD [+βGD ]RQ operationalized
Can βGD be considered as zero or not?
10 / 30

Type-sensitive approach
Disability types (self-reported) are handled
separately to explore the possibility of diﬀerence inwork disadvantage
Statistical definition of disability

A significant or strong association between a bodily condition and a social exclusion measure→Disabilities are called “limitations” until theirassociations with some exclusion metric areconfirmed
11 / 30

Data description
The microdata of Irish Census 2011
Disability-related information is included
Available from the IPUMS-International
database[5]Data size(a 10% subsample)
Working-aged persons(age 15-64)

474,353
303,773

12 / 30

Basic statistics
Age(S.D.)
FemaleEducation: Primary
Lower Secondary
Upper Secondary
Tertiary (non-degree)
Tertiary (degree+)Religion: Catholic
COI/Protestant
Other
None

38.34
13.37
50.50%
9.93%
19.20%
38.50%
5.08%
27.29%
84.12%
2.84%
5.70%
7.34%

Irish language
Irish ethnicity
Limitations:
VisualHearing
PhysicalIntellectual
Learning
Psychological
OTher

39.08%
84.42%
0.76%1.17%
3.35%
1.04%
2.11%
2.26%
5.09%

N = 286845. Among persons with one or more bodily limitations(30,040), 9,842 persons reported multiple limitations, among whom
5,467 had more than one specified (except for ”Other”) limitations.

13 / 30

Employment status (%, N=286,845)
W
None
64.9
Visual
35.3
Hearing
46.1
Physical
17.2
Intellectual
17.3
Learning
22.5
Psychological 19.3
Other33.8

MaleU
I
16.4 1.0
16.9 32.2
18.0 20.0
12.7 57.9
11.5 51.6
16.7 36.1
18.0 47.7
15.1 36.9

FemaleWUI
58.2 8.4 0.9
31.5 9.9 28.6
38.5 10.7 19.4
18.3 7.7 49.6
14.4 5.6 55.7
19.8 11.2 37.0
23.8 11.7 38.4
30.5 8.7 33.8

W: working, U: unemployed, I: incapacitated
Other categories were dropped from the table. 14 / 30

Employment status (%, N=163,058)
MaleM
PE
None
11.3 16.1 9.4
Visual10.8 14.7 12.9
Hearing
9.0 12.2 11.6
Physical
7.9 8.3 14.5
Intellectual
3.9 2.7 29.8
Learning
5.8 5.5 19.4
Psychological 7.0 15.8 14.3
Other
10.1 15.2 10.7Female
M PE
7.0 24.5 7.6
5.1 16.1 11.6
7.8 15.6 10.3
6.3 16.4 10.2
2.6 7.0 27.8
3.7 8.9 18.1
5.6 17.2 8.3
7.1 24.3 8.5

M: managerial, P: professional, E: elementary
Other categories were dropped from the table. 15 / 30

Logit Model 1: employment status
Dependent :p orking
Stage 1: log pN W
otW orking
ppHomemakerStage 2: log pU nemployed , log pIncapacitated, ...
U nemployed
Independent : Age, Age2 , Gender, Education(Dummy), Religion (Dummy), Irish language ability,Irish ethnicity, Disability types
Interaction : Gender*Disability types
N = 286845 (complete cases)

16 / 30

Logit Model 2: occupationpp

M anagerial
rof essional
Dependent : log pElementary, log pPElementary, ...

Independent : Age, Age2 , Gender, Education(Dummy), Religion (Dummy), Irish language ability,Irish ethnicity, Disability types
Interaction : Gender*Disability types
N = 163058 (complete cases, working)17 / 30

Model fit

AIC
Model 1 Stage 1
312125.8(Without interaction) 312237
Model 1 Stage 2213430(Without interaction) 213370.4
Model 2570243.7(Without interaction) 570192.8

BIC312411.1
312448.3215141.8214638.4
572404.1
571793.1

18 / 30

Model fit and interaction

Interaction between gender and disability types is:
Rejected concerning Model 1 Stage 2(unemployment/other non-working options)and Model 2 (occupation)
Accepted concerning Model 1 Stage 1(working/not working)19 / 30

Model 1 Stage 1 (with interaction)

Age
Age2
FemaleEducation (ref. Primary)Lower Secondary
Upper Secondary
Tertiary (non-degree)
Tertiary (degree+)(Continued)

1.79**
0.50**0.62**
1.41**
2.70**
3.95**
6.61**

Religion (ref. Catholic)
COI/Protestant 0.85**
Other
0.61**
None
0.80**
Irish language
1.03**
Irish ethnicity
1.09**

20 / 30

Model 1 Stage 1 (with interaction)
Limitations
VisualHearing
PhysicalIntellectual
Learning
Psychological
Other
McFadden

0.58**
0.80**
0.20**
0.58**
0.63**
0.17**
0.49**
0.20**

Gender*Limitations
F*Visual
F*Hearing
F*Physical
F*Intellectual
F*Learning
F*Psychological
F*Other

1.18
0.97
1.45**
1.09
1.13
1.75**
1.01∗∗ : p < .01, ∗ : p < .05, intercept omitted
Age is normalized by (Age-Mean)/S.D.

21 / 30

Model 1 Stage 1 (with interaction)

All limitation types as well as being a woman
are negatively correlated with work opportunity
On the whole the disadvantage for women withlimitation is additive (multiplicative whenexponentiated)
For women with physical and psychologicallimitation, the disadvantage by being a woman
is nealy oﬀset.

22 / 30

Stage 2 (without interaction)
Age
Age2Female
Education (ref. Primary)Lower Secondary
Upper SecondaryTertiary (non-degree)
Tertiary (degree+)Religion (ref. Catholic)
COI/Protestant
Other
None
McFadden

2.20**
1.07**
1.71**
0.98
0.76**
0.61**
0.54**
0.84*
0.85*
0.76**
0.43**

Irish language
Irish ethnicity
Limitations
VisualHearing
PhysicalIntellectual
Learning
Psychological
OTher

1.12**
1.77**
2.28**
1.26**
8.94**
12.68**
1.27**
8.61**
4.72**

Only incapacity/unemployed odds ratios are provided∗∗ : p < .01, ∗ : p < .05, intercept omitted
Age is normalized by (Age-Mean)/S.D.

23 / 30

Unemployment and incapacity
The tendency among non-working persons toclassify their status as incapacitated rather thanunemployed is stronger among:
Persons with all limitation types (in varyingdegrees)
Women
Persons with less education
Persons with Irish language ability and/or Irish
ethnicity
The disadvantage for women with some limitation isadditive(The odds ratios are multiplied)
24 / 30

Model 2 (without interaction)
Age
Age2
FemaleEducation (ref. Primary)Lower Secondary
Upper Secondary
Tertiary (non-degree)
Tertiary (degree+)Religion (ref. Catholic)
COI/Protestant
Other
None(Continued)

Managerial
1.81**
0.76**
0.66**

Professional
1.80**
0.84**
1.52**

2.42**
6.82**
15.77**
43.62**

18.51**
102.87**873.69**7843.62**

2.90**
1.11**
1.56**

2.81**
1.64**
2.02**

25 / 30

Model 2 (without interaction)
Irish language
Irish ethnicity
Limitations
VisualHearing
PhysicalIntellectual
Learning
Psychological
Other
McFaddenManagerial
1.37**
4.91**

Professional
2.06**
5.74**

0.85**
0.73**
0.69**
0.53**
0.45**
0.62**
1.22**
0.18**

0.77**
0.77**
0.70**
0.24**
0.40**
0.71**
1.02**

Other occupations dropped from the table∗∗ : p < .01, ∗ : p < .05, intercept omitted
Age is normalized by (Age-Mean)/S.D.

26 / 30

Women with disabilities and occupation

Women are underrepresented among managers
but overrepresented among professionals
Persons with some limitation areunderrepresented among managers andprofessionals
Education has a very strong favorable eﬀet
Additive eﬀects for women with some limitation(The odds ratios are multiplied)

27 / 30

Discussion
Interactions are only partially supported
Interactions regarding the odds of ”working”p) for some limitation types alleviate( 1−pWWorkingorking
multiple disadvantages
Additive (multiplicative when exponentiated)
eﬀects in the models roughly correspond tomultiple disadvantages, although women are
more likely than men to be in professional
occupation
28 / 30

Conclusion and acknowledgements
Intersectionality of disability types and gender
mainly as additivity rather than interaction
Multiple exclusion of women with bodily
limitations from the labor market
Additive eﬀects on social stratification
This work was supported by JSPS KAKENHI (Grant No. 18K12950).
The author wishes to acknowledge the statistical oﬃce that provided theunderlying data making this research possible: Central Statistics Oﬃce,
Ireland. The author is also grateful to the Minnesota Population Center,
which manages the IPUMS International database.

29 / 30

References
1

Convention on the Rights of Persons with Disabilities,
A/RES/61/106.

2

Moodley, J. and L. Graham (2015), “The importance ofintersectionality in disability and gender studies,” Agenda, 29(2):24–33.
Walby, S. et al.(2012), “Intersectionality,” Sociology, 46(2):
224–240.
Söder, M. (2009), “Tensions, perspectives and themes in disability
studies,” Scandinavian Journal of Disability Research, 11(2):67–81.
Minnesota Population Center (2017) “Integrated Public Use
Microdata Series, International,” Available athttps://doi.org/10.18128/D020.V6.5 .

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