Far and few between? The child-bearing decisions of Portuguese women

Author: Márton Varga

Conference on the Impact of Day-Care Services in Visegrad Countries. Budapest, 2012.

Amélia

-Born in 1961-Lives in Braga-Has 10 siblings

Madalena

-Born in 1958-Lives in Lisbon-Has 2 siblings

Sofia

-Born in 1965-Lives in Faro-No sisters or brothers

Can we predict their childbearing decisions?

QUESTIONS

Main source: Fertility and Family Survey

DATA and METHODOLOGY

How many children will women have?

When do they give birth?

Technique: Split-population survival estimation

Sample: 5484 Portuguese women (1947-79)

MAIN RESULTS

Education leads to delayed childbearing and a longer interval between the second and third birth. University graduates are more likely to have the third child.

More siblings are associated with a higher probability of having the second child.

Younger cohorts are more likely to postpone childbearing, to remain childless, and to have fewer children.

Changes in the unemployment rate and childcare availability do not influence fertility timing.

Mothers, who were older at their last delivery, have a lower probability of the consequent birth, but they wait less if they decide to have another child.

10% remain childless, 30 % stop at one child, while 70% stop at two children.

Education

Siblings

Cohort

Economy

Age at birth

Other

Birthplace, education and age at first birth explains who stops at one child.

Nick Parr (2007)

Women who delay are more educated and skilled.

Kasey Buckles(2008)

Childcare availability increases fertility.

Ronald R. Rindfuss et al. (2007)

Regional female unemployment leads to delayed childbearing.

Maria D. Gutiérrez(2008)

Split-population models for 3rd and 4th birth.Focus on sex composition, age at first birth, and father’s

occupation.

Edith Gray et al. (2010)

MOTIVATION

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FIRST BIRTH SURVIVALS(t)

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SECOND BIRTH SURVIVALS(t)

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THIRD BIRTH SURVIVALS(t)

FIGURE 1. KAPLAN MEIER SURVIVAL ESTIMATESNote: Duration is measured from the age of 14 and from the 3rd quarter after the last birth.

(1 )𝑆 (𝑡 )=1−∫0

𝑡

𝑓 (𝑠 )𝑑𝑠=1−𝐹 (𝑡 )=𝜋 𝐹𝑢(𝑡 )

(2 ) 𝜋=𝑒−𝑒(𝛼′ 𝑋+𝜀)

(3 ) 𝑓 𝑢 (𝑡 )=𝑒−( 𝛽 ′𝑍 )𝜎 [𝑒−(𝛽 ′𝑍 )𝑡 ]𝜎𝜅−1𝑒− [𝑒−( 𝛽 ′ 𝑍 )𝑡 ]𝜎

Γ (κ)

Important• means lower probability of

NOT having another child.• means longer waiting time.

(4) ln𝑇=𝛽′ 𝑍+1𝜎𝜈

THE SPLIT-POPULATION MODEL

TABLE 3 - TRANSITION TO THE THIRD BIRTHα β

Secondary 0.054 0.592**(0.241) (0.265)

University 1.286*** 0.808**(0.379) (0.361)

One -0.147 -0.381(0.262) (0.284)

Two 0.082 -0.109(0.263) (0.284)

Three or more 0.396* -0.221(0.234) (0.249)

Born 1960-79 -0.310*** -0.062(0.111) (0.152)

Unemployment change -0.016(0.062)

Childcare change -0.012(0.018)

Age at second birth -0.181*** -0.040**(0.013) (0.016)

Constant 4.076*** 2.738***(0.403) (0.517)

District dummies YES YESPeriod effects NO YESln σ -0.121

(0.086)

κ 0.401**(0.188)

Log-likelihood -2310.73Number of subjects 2101Observations 18,169Note: Standard errors in parentheses. ***Significant at 1%. **Significant at 5%. *Significant at 10%.

Education

Siblings

Cohort

Economy

Age at birth

Amélia

-Born in 1961-Lives in Braga-Has 10 siblings-Received primary education-Second child at 20

Madalena

-Born in 1958-Lives in Lisbon-Has 2 siblings-Attended university-Second child at 28

Sofia

-Born in 1965-Lives in Faro-No sisters or brothers-Finished secondary school-Second child at 27

Probability of stop at two

children33.9%

Probability of stop at two

children81.7%

Probability of stop at two

children86.3%

70.4% stop at two children

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THIRD BIRTH SURVIVALS(t)

Results are robust

Deserves more investigation

Results are plausible

FINAL REMARKS

Thank you for the attention!

TABLE 1 - TRANSITION TO THE FIRST BIRTHα β

Secondary -0.183 0.373***(0.113) (0.042)

University 0.072 0.571***(0.214) (0.075)

One -0.087 -0.004(0.121) (0.046)

Two 0.010 -0.008(0.123) (0.047)

Three or more -0.114 -0.096**(0.107) (0.041)

Born 1960-79 -0.149** 0.000(0.060) (0.036)

Unemployment change -0.024**(0.011)

Childcare change -0.006(0.004)

Constant 0.876*** 2.774***(0.119) (0.053)

District dummies YES YESPeriod effects NO YESln σ -0.956***

(0.039)κ 0.516***

(0.053)Log-likelihood -11042.97Number of subjects 5484Observations 63,593Note: Standard errors in parentheses. ***Significant at 1%. **Significant at 5%. *Significant at 10%.

Education

Siblings

Cohort

Economy

TABLE 2 - TRANSITION TO THE SECOND BIRTHα β

Secondary -0.030 0.010(0.093) (0.067)

University 0.078 -0.119(0.140) (0.095)

One 0.229** 0.070(0.113) (0.079)

Two 0.348*** 0.085(0.116) (0.082)

Three or more 0.427*** 0.051(0.102) (0.069)

Born 1960-79 -0.209*** -0.097(0.070) (0.071)

Unemployment change 0.015(0.027)

Childcare change -0.007(0.008)

Age at first birth -0.074*** -0.046***(0.008) (0.006)

Constant 1.904*** 2.916***(0.221) (0.197)

District dummies YES YESPeriod effects NO YESln σ -0.700***

(0.062)

κ 1.489***(0.123)

Log-likelihood -6108.71Number of subjects 3353Observations 21,139Note: Standard errors in parentheses. ***Significant at 1%. **Significant at 5%. *Significant at 10%.

Education

Siblings

Cohort

Economy

Age at birth

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FIRST BIRTH SURVIVALS(t)

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FIRST BIRTH HAZARDh(t)

FIGURE 1. FIRST BIRTH TIMING, KAPLAN MEIER SURVIVAL AND SMOOTHED HAZARD ESTIMATESNote: Duration is measured from the age of 14.

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SECOND BIRTH SURVIVALS(t)

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SECOND BIRTH HAZARDh(t)

FIGURE 2. SECOND BIRTH TIMING, KAPLAN MEIER SURVIVAL AND SMOOTHED HAZARD ESTIMATESNote: Duration is measured from the 3rd quarter after the first delivery.

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THIRD BIRTH SURVIVALS(t)

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THIRD BIRTH HAZARDh(t)

FIGURE 3. FIRST BIRTH TIMING, KAPLAN MEIER SURVIVAL AND SMOOTHED HAZARD ESTIMATESNote: Duration is measured from the 3rd quarter after the second delivery.