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Quadratic fractional age assumption revisited
1Department of Mathematics and Statistics, University of Nebraska, Kearney, NE 68849, USA. hossains@unk.edu
Lifetime Data Analysis
|February 19, 2010
Summary
This study introduces a new quadratic fractional age assumption for continuous mortality and survival functions. This method allows for more accurate estimation of life table parameters using real-world data.
Area of Science:
- Actuarial Science
- Demography
- Mathematical Statistics
Background:
- Traditional life table models often assume discrete age intervals, leading to discontinuities in mortality and survival functions.
- Continuous functions are crucial for precise actuarial calculations and demographic projections.
Purpose of the Study:
- To introduce and validate a novel quadratic fractional age assumption.
- To ensure continuity of the force of mortality and survival function across all ages.
- To enhance the accuracy of life table parameter estimation.
Main Methods:
- Derivation of the necessary and sufficient conditions for the validity of the quadratic fractional age assumption.
- Estimation of key life table parameters under the new assumption.
- Application and validation using established life table datasets.
Main Results:
- The quadratic fractional age assumption ensures continuous force of mortality and survival functions.
- The derived conditions provide a clear criterion for the assumption's applicability.
- Accurate estimation of life table parameters was demonstrated.
Conclusions:
- The quadratic fractional age assumption offers a significant improvement for continuous modeling in actuarial science.
- This approach enhances the reliability of life table data and demographic analyses.
- The method is practical and validated by real-world life table applications.
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