Why life expectancy over-predicts crude death rate
Abstract Life expectancy is widely used and reported; for example, the UN Human Development Index uses life expectancy as a key component. But many users of period life expectancy do not understand and interpret life expectancy as demographers do. In particular, period life expectancy almost always...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2023-04-01
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| Series: | Genus |
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| Online Access: | https://doi.org/10.1186/s41118-023-00188-8 |
| _version_ | 1797836554767433728 |
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| author | Haili Liang Zhen Guo Shripad Tuljapurkar |
| author_facet | Haili Liang Zhen Guo Shripad Tuljapurkar |
| author_sort | Haili Liang |
| collection | DOAJ |
| description | Abstract Life expectancy is widely used and reported; for example, the UN Human Development Index uses life expectancy as a key component. But many users of period life expectancy do not understand and interpret life expectancy as demographers do. In particular, period life expectancy almost always over-predicts the crude death rate. Indeed, in most observed populations, the annual deaths recorded are always less than one may expect in the corresponding stationary population. To explain this over-prediction, in this paper we analyze how deviations from stationarity affect the crude death rate. We use theory to show that small deviations from the stationary age structure (as high as 20% at each age) always lead to over-prediction. Then we examine global data to show that over-prediction is widespread, occurring even in populations where the deviation from stationarity is large. Finally, we show that populations around the world and over many decades have age structures that are almost always far from stationary (or indeed, stability). But we also show that the deviation is often due to the demographic transition, with population bulges at the middle ages where mortality is low. |
| first_indexed | 2024-04-09T15:11:54Z |
| format | Article |
| id | doaj.art-7acc6eed43f44997bb7cc6015ee0f172 |
| institution | Directory Open Access Journal |
| issn | 2035-5556 |
| language | English |
| last_indexed | 2024-04-09T15:11:54Z |
| publishDate | 2023-04-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Genus |
| spelling | doaj.art-7acc6eed43f44997bb7cc6015ee0f1722023-04-30T11:10:20ZengSpringerOpenGenus2035-55562023-04-0179111410.1186/s41118-023-00188-8Why life expectancy over-predicts crude death rateHaili Liang0Zhen Guo1Shripad Tuljapurkar2Sociology School, Huazhong University of Science and TechnologySociology School, Huazhong University of Science and TechnologyBiology Department, Stanford UniversityAbstract Life expectancy is widely used and reported; for example, the UN Human Development Index uses life expectancy as a key component. But many users of period life expectancy do not understand and interpret life expectancy as demographers do. In particular, period life expectancy almost always over-predicts the crude death rate. Indeed, in most observed populations, the annual deaths recorded are always less than one may expect in the corresponding stationary population. To explain this over-prediction, in this paper we analyze how deviations from stationarity affect the crude death rate. We use theory to show that small deviations from the stationary age structure (as high as 20% at each age) always lead to over-prediction. Then we examine global data to show that over-prediction is widespread, occurring even in populations where the deviation from stationarity is large. Finally, we show that populations around the world and over many decades have age structures that are almost always far from stationary (or indeed, stability). But we also show that the deviation is often due to the demographic transition, with population bulges at the middle ages where mortality is low.https://doi.org/10.1186/s41118-023-00188-8SensitivityCrude death rateLife expectancy |
| spellingShingle | Haili Liang Zhen Guo Shripad Tuljapurkar Why life expectancy over-predicts crude death rate Genus Sensitivity Crude death rate Life expectancy |
| title | Why life expectancy over-predicts crude death rate |
| title_full | Why life expectancy over-predicts crude death rate |
| title_fullStr | Why life expectancy over-predicts crude death rate |
| title_full_unstemmed | Why life expectancy over-predicts crude death rate |
| title_short | Why life expectancy over-predicts crude death rate |
| title_sort | why life expectancy over predicts crude death rate |
| topic | Sensitivity Crude death rate Life expectancy |
| url | https://doi.org/10.1186/s41118-023-00188-8 |
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