The dynamics of insect numbers 1: history, classical theories, time series, life tables, models.

We construct cohort working life tables for Canadian men and women aged 50 and older and, for comparison, corresponding period tables. The tables are derived using annual single-age time series of participation rates for 1976-2006 from the master files of the Statistics Canada Labour Force Survey. The cohort calculations are based on stochastic projections of mortality coupled with alternative assumptions about future participation rates. Separate tables are provided for the years 1976, 1991, and 2006, thus spanning a period of substantial gains in life expectancy and strong upward trends in female participation. Life expectancies based on the cohort tables are greater than those based on the period tables, for both men and women, and that is reflected in increased retirement expectancies. For example, a male aged 50 in 1976 could have expected to live three years longer and to have almost four more years in retirement, based on the male cohort table under medium assumptions, as compared with the corresponding period table.

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Mortality models incorporating long memory for life table estimation: a comprehensive analysis

Annals of Actuarial Science ◽

10.1017/s1748499521000014 ◽

2021 ◽

pp. 1-38

Author(s):

Hongxuan Yan ◽

Gareth W. Peters ◽

Jennifer Chan

Keyword(s):

Time Series ◽

Life Expectancy ◽

Long Memory ◽

Age Groups ◽

Deviance Information Criterion ◽

Information Criterion ◽

Life Tables ◽

Mortality Data ◽

Model Parameters ◽

Mortality Models

Abstract Mortality projection and forecasting of life expectancy are two important aspects of the study of demography and life insurance modelling. We demonstrate in this work the existence of long memory in mortality data. Furthermore, models incorporating long memory structure provide a new approach to enhance mortality forecasts in terms of accuracy and reliability, which can improve the understanding of mortality. Novel mortality models are developed by extending the Lee–Carter (LC) model for death counts to incorporate a long memory time series structure. To link our extensions to existing actuarial work, we detail the relationship between the classical models of death counts developed under a Generalised Linear Model (GLM) formulation and the extensions we propose that are developed under an extension to the GLM framework known in time series literature as the Generalised Linear Autoregressive Moving Average (GLARMA) regression models. Bayesian inference is applied to estimate the model parameters. The Deviance Information Criterion (DIC) is evaluated to select between different LC model extensions of our proposed models in terms of both in-sample fits and out-of-sample forecasts performance. Furthermore, we compare our new models against existing models structures proposed in the literature when applied to the analysis of death count data sets from 16 countries divided according to genders and age groups. Estimates of mortality rates are applied to calculate life expectancies when constructing life tables. By comparing different life expectancy estimates, results show the LC model without the long memory component may provide underestimates of life expectancy, while the long memory model structure extensions reduce this effect. In summary, it is valuable to investigate how the long memory feature in mortality influences life expectancies in the construction of life tables.

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Multiple approaches to estimating the relative importanceof top-down and bottom-up forces on insect populations:Experiments, life tables, and time-series analysis

Basic and Applied Ecology ◽

10.1078/1439-1791-00068 ◽

2001 ◽

Vol 2 (4) ◽

pp. 295-309 ◽

Cited By ~ 63

Author(s):

Mark D. Hunter

Keyword(s):

Time Series ◽

Time Series Analysis ◽

Life Tables ◽

Top Down ◽

Bottom Up ◽

Series Analysis

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The LDE-Type Flare Occurrence (1969-1993)

International Astronomical Union Colloquium ◽

10.1017/s0252921100025458 ◽

1994 ◽

Vol 144 ◽

pp. 279-282

Author(s):

A. Antalová

Keyword(s):

Time Series ◽

Fourier Analysis ◽

Sunspot Cycle ◽

List Type ◽

Type Number ◽

Solar Cycles ◽

Type Iv ◽

Long Duration ◽

Cycle Maximum ◽

Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

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