Ever-Married by Age Interpolation Calculator
Linearly interpolate the proportion ever married at a target age from group values placed at five-year-group midpoints, holding the endpoint groups constant outside their midpoints.
Description
Linearly interpolate the proportion ever married at a target age from group values placed at five-year-group midpoints, holding the endpoint groups constant outside their midpoints.
Linearly interpolate the proportion ever married at a target age from group values placed at five-year-group midpoints, holding the endpoint groups constant outside their midpoints.1
When to use Ever-Married by Age Interpolation Calculator
Use this interpolation method to disaggregate or estimate values only when the grouped observations and coefficient layout match the method's required age ordering.
- Ever married
- Proportion ever married in each successive age group.
- Target age
- Exact age at which to interpolate the proportion ever married.
- Start age
- Age at the start of the first group.
- Group width
- Width of each age group in years.
How the method works
- Ever married
- Interpolated proportion ever married at the target age.
Limitations and assumptions
Interpolation creates model-based values rather than new observations. Edge groups, abrupt cohort changes, sparse counts, and coefficients intended for a different grouping scheme can produce implausible results.
Alternative or Complementary measures
Compare the interpolated series with a simpler linear allocation and inspect whether totals are preserved. When single-year observations exist, prefer them over values reconstructed from grouped data.
References
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Interpolation — Wikipedia contributors
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