@article{KWW2008c,
    TITLE = {Age Structure Changes and Extraordinary Lifespan in Wild Medfly
             Populations},
   AUTHOR = {James R. Carey and Nikos T. Papadopoulous and Hans-Georg M"{u}ller
             and Byron I. Katsoyannos and Nikos A. Kouloussis and Jane-Ling Wang
             and Kenneth Wachter and Wei Yu and and Pablo Liedo},
  JOURNAL = {Aging Cell},
   VOLUME = {7},
    PAGES = {426--437},
     YEAR = {2008},
       ID = {info:doi/10.1111/j.1474-9726.2008.00390.x},
 ABSTRACT = {The main purpose of this study was to test the hypotheses that
             major changes in age structure occur in wild populations of the
             Mediterranean fruit fly (medfly) and that a substantial fraction of
             individuals survive to middle age and beyond (> 3--4 weeks). We
             thus brought reference life tables and deconvolution models to bear
             on medfly mortality data gathered from a 3-year study of field-
             captured individuals that were monitored in the laboratory. The
             average time-to-death of captured females differed between sampling
             dates by 23.9, 22.7, and 37.0 days in the 2003, 2004, and 2005
             field seasons, respectively. These shifts in average times-to-death
             provided evidence of changes in population age structure. Estimates
             indicated that middle-aged medflies (> 30 days) were common in the
             population. A surprise in the study was the extraordinary longevity
             observed in field-captured medflies. For example, 19 captured
             females but no reference females survived in the laboratory for 140
             days or more, and 6 captured but no reference males survived in the
             laboratory for 170 days or more. This paper advances the study of
             aging in the wild by introducing a new method for estimating age
             structure in insect populations, demonstrating that major changes
             in age structure occur in field populations of insects, showing
             that middle-aged individuals are common in the wild, and revealing
             the extraordinary lifespans of wild-caught individuals due to their
             early life experience in the field.},
   }

        

@article{KWW2008d,
    TITLE = {Biodemography Comes of Age},
   AUTHOR = {Kenneth W. Wachter},
  JOURNAL = {Demographic Research},
   VOLUME = {19},
   NUMBER = {40},
    PAGES = {1501--1512},
      URL = {http://www.demographic-research.org/volumes/vol19/40/},
    MONTH = {August},
     YEAR = {2008},
 ABSTRACT = {Biodemography has emerged and grown over the last fifteen years,
             with loyal and farsighted support from its patrons. As it enters
             what might be called its adolescence as a field, it faces
             challenges along with abounding opportunities. One challenge is to
             continue to generate knowledge that contributes to human health and
             well-being. A second is to insist on high standards of quality
             control within its cross-disciplinary environment. Opportunities
             appear in a variety of directions, including mathematical modeling,
             genomic analyses, and field studies of aging in the wild.},
   }

        

@article{KWW2006a,
    TITLE = {Understanding Mortality Rate Deceleration and Heterogeneity},
   AUTHOR = {David R. Steinsaltz and Kenneth W. Wachter},
  JOURNAL = {Mathematical Population Studies},
   VOLUME = {13},
   NUMBER = {1},
    PAGES = {19--37},
     YEAR = {2006},
       ID = {info:doi/10.1080/08898480500452117},
 ABSTRACT = {Generic relationships between heterogeneity in population frailty
             and flattening of aggregate population hazard functions at extreme
             ages are drawn from classical mathematical results on the limiting
             behavior of Laplace transforms. In particular, it shows that the
             population hazard function converges to a constant precisely when
             the distribution of unobserved heterogeneity in initial mortalities
             behaves asymptotically as a polynomial near zero.},
   }

        

@article{KWW2006b,
    TITLE = {Relationships between Period and Cohort Life Expectancy: Gaps and
             Lags},
   AUTHOR = {Joshua R. Goldstein and Kenneth W. Wachter},
  JOURNAL = {Population Studies},
   VOLUME = {60},
   NUMBER = {3},
    PAGES = {257--269},
    MONTH = {November},
     YEAR = {2006},
       ID = {info:doi/10.1080/00324720600895876},
 ABSTRACT = {This paper offers an empirical and analytic foundation for
             regarding period life expectancy as a lagged indicator of the
             experience of real cohorts in populations experiencing steady
             improvement in mortality. We find that current period life
             expectancy in the industrialized world applies to cohorts born some
             40-50 years ago. Lags track an average age at which future years of
             life are being gained, in a sense that we make precise. Our
             findings augment Ryder's classic results on period-cohort
             translation.},
   }

        

@article{STEINSALTZ:0000:AGMOMB,
   AUTHOR = {Steinsaltz, David R. and Evans, Steven N. and Wachter, Kenneth W.},
    TITLE = {A generalized model of mutation-selection balance with applications
             to aging},
  JOURNAL = {Advances in Applied Mathematics},
   VOLUME = {35},
   NUMBER = {1},
    PAGES = {16--33},
     YEAR = {2005},
      URL = {http://www.mast.queensu.ca/~steinsaltz/papers/ms.pdf},
       ID = {info:oai/arXiv.org:q-bio.PE/0403002,
             info:doi/10.1016/j.aam.2004.09.003},
 ABSTRACT = {A probability model is presented for the dynamics of mutation--
             selection balance in a haploid infinite-population infinite-sites
             setting sufficiently general to cover mutation-driven changes in
             full age-specific demographic schedules. The model accommodates
             epistatic as well as additive selective costs. Closed form
             characterizations are obtained for solutions in finite time, along
             with proofs of convergence to stationary distributions and a proof
             of the uniqueness of solutions in a restricted case. Examples are
             given of applications to the biodemography of aging.},
   }

        

@article{KWW2005b,
    TITLE = {Spatial Demography},
   AUTHOR = {Kenneth W. Wachter},
  JOURNAL = {Proc. Natl. Acad. Sci. Unit. States Am.},
   VOLUME = {102},
   NUMBER = {43},
    PAGES = {15299--15300},
    MONTH = {October},
     YEAR = {2005},
       ID = {info:doi/10.1073/pnas.0508155102},
     NOTE = {No abstract. Introduction to this issue of PNAS},
   }

        

@article{KWW2005c,
    TITLE = {Tempo and its Tribulations},
   AUTHOR = {Kenneth W. Wachter},
  JOURNAL = {Demographic Research},
   VOLUME = {13},
   NUMBER = {9},
    PAGES = {201--222},
    MONTH = {November},
     YEAR = {2005},
 ABSTRACT = {Bongaarts and Feeney offer alternatives to period life expectancy
             with a set of demographic measures equivalent to each other under a
             Proportionality Assumption. Under this assumption, we show that the
             measures are given by exponentially weighted moving averages of
             earlier values of period life expectancy. They are indices of
             mortality conditions in the recent past. The period life expectancy
             is an index of current mortality conditions. The difference is a
             difference between past and present, not a ``tempo distortion'' in
             the present. In contrast, the Bongaarts-Feeney tempo-adjusted Total
             Fertility Rate is a measure of current fertility conditions, which
             can be understood in terms of a process of birth-age
             standardization.},
      URL = {http://www.demographic-research.org/volumes/vol13/9},
   }

        

@article{WACHTER:2003:TPPAFO,
   AUTHOR = {Wachter, Kenneth W.},
    TITLE = {The past, present, and future of demography and the role of the
             {M}ax {P}lanck {I}nstitute for {D}emographic {R}esearch},
  JOURNAL = {Demographic Research},
     ISSN = {1435-9871},
   VOLUME = {9},
     YEAR = {2003},
      URL = {http://www.demographic-research.org/volumes/vol9/4},
 ABSTRACT = {Demography, within the memories of those now living,has been shaped
             by a few outstanding centers,the Institut National d'Etudes
             Demographiques,the Cambridge Group for the History of Population
             and Social Structure, and the Princeton Office of Population
             Research. The Max Planck Institute for Demographic Research, whose
             new building received a festive dedication on 31 March 2003, now
             joins this distinguished family.},
   }

        

@article{WACHTER:2003:PBHIOA,
   AUTHOR = {Wachter, Kenneth W. and Knodel, John E. and VanLandingham, Mark},
    TITLE = {Parental bereavement: heterogeneous impacts of {AIDS} in {T}hailand},
  JOURNAL = {J. Econometrics},
 FJOURNAL = {Journal of Econometrics},
     ISSN = {0304-4076},
   VOLUME = {112},
   NUMBER = {1},
     YEAR = {2003},
    PAGES = {193--206},
    CODEN = {JECMB6},
  MRCLASS = {Database Expansion Item},
ZBLABSTRACT = {Over the coming decades in Thailand, aging parents whose adult
             children sicken with AIDS will bear burdens of caregiving and loss.
             Using demographic microsimulations, we show that the new, lower
             projections of the HIV/AIDS epidemic still imply that $8\%$ of
             Thais over the age of 50 in 1995 will lose one or more children to
             AIDS before their own deaths. The proportion of all losses which
             are multiple losses can vary from $12\%$ to $33\%$ under a range of
             assumptions about plausible family-to-family heterogeneity in risks
             of infection.},
 ZBLCLASS = {92D30;91D20},
       ID = {info:zbl/1008.92033, info:mr/MR1963238,
             info:doi/10.1016/S0304-4076(02)00160-4},
   }

        

@article{WACHTER:2002:AATEOT,
   AUTHOR = {Wachter, Kenneth W. and Knodel, John E. and VanLandingham, Mark J.},
    TITLE = {AIDS and the elderly of {T}hailand: Projecting familial impacts},
  JOURNAL = {Demography},
   VOLUME = {39},
     YEAR = {2002},
    PAGES = {25--41},
      URL = {http://muse.jhu.edu/login?uri=/journals/demography/v039/39.1wachter.html},
 ABSTRACT = {We apply aggregate demographic analysis and computer
             microsimulation to project the number of older Thais who will lose
             children to AIDS during their own lifetimes and to assess their
             involvement with ill children through caregiving and coresidence.
             Parental bereavements from AIDS are predicted to peak at around
             80,000 per year between 2003 and 2007. Despite an HIV prevalence of
             only $2\%, 13\%$ of Thais who were over age 50 as of 1995 are
             likely to experience the loss of at least one adult child to AIDS,
             and $12\%$ of them will lose multiple children. The chance of
             losing an adult child during one's lifetime will be $70\%$ higher
             than if there were no AIDS epidemic. The impacts of the worldwide
             epidemic of HIV-AIDS extend far beyond the infected individuals
             themselves. Demographic disruptions, recognized early by Palloni
             and Lee (1992), loom ever larger. A host of emotional, economic,
             social, and physical strains on family members have been surveyed
             by Bloom and Godwin (1997), Bor and Elford (1994), and Patel
             (1995). Orphanhood and the plight of children whose parents are
             living with or dying of AIDS are attracting particular attention...},
  EDNOTES = {<abpart>},
   }

        

@article{FREEDMAN:2001:CASPOI,
   AUTHOR = {Freedman, David and Wachter, Kenneth W.},
    TITLE = {Census adjustment: Statistical promise or illusion?},
  JOURNAL = {Society},
   VOLUME = {39},
     YEAR = {2001},
    PAGES = {26--33},
       ID = {info:doi/10.1007/BF02712617},
     NOTE = {without abstract},
   }

        

@article{FREEDMAN:2001:APMFCA:0990.91050,
   AUTHOR = {Freedman, David A. and Stark, Philip and Wachter, Kenneth W.},
    TITLE = {A probability model for census adjustment},
  JOURNAL = {Mathematical Population Studies},
     ISSN = {0889-8480},
   VOLUME = {9},
     YEAR = {2001},
    PAGES = {165--180},
ZBLABSTRACT = {The census can be adjusted using capture-recapture techniques:
             capture in the census, recapture in a special Post Enumeration
             Survey (PES) done after the census. The population is estimated
             using the Dual System Estimator (DSE). Estimates are made
             separately for demographic groups called post strata; adjustment
             factors are then applied to these demographic groups within small
             geographic areas. We offer a probability model for this process, in
             which several sources of error can be distinguished. In this model,
             correlation bias arises from behavioral differences between persons
             counted in the census and persons missed by the census. The first
             group may on the whole be more likely to respond to the PES: if so,
             the DSE will be systematically too low, and that is an example of
             correlation bias. Correlation bias is distinguished from
             heterogeneity, which occurs if the census has a higher capture rate
             in some geographic areas than others. Finally, ratio estimator bias
             and variance are considered. The objective is to clarify the
             probabilistic foundations of the DSE, and the definitions of
             certain terms widely used in discussing that estimator.},
 ZBLCLASS = {91D20},
       ID = {info:zbl/0990.91050},
   }

        

@article{WACHTER:2000:MLHWCD,
   AUTHOR = {Wachter, Kenneth W. and Freedman, David A.},
    TITLE = {Measuring local heterogeneity with 1990 census data},
  JOURNAL = {Demographic Research},
   VOLUME = {3},
   NUMBER = {10},
     YEAR = {2000},
      URL = {http://www.demographic-research.org/volumes/vol3/10/},
 ABSTRACT = {A sample covering 204,394 blocks from the 1990 U.S. Census permits
             measurement of residual heterogeneity from local area to local area
             after controlling by stratification for demographic characteristics
             such as race, ethnicity, age, sex as well as geographic
             characteristics such as region and place-type. The local areas have
             populations on the order of 10,000 people. The variables studied
             are four indices of enumeration difficulty. The results show that
             variance due to heterogeneity from area to area is comparable to
             (if not larger than) variance from stratum to stratum and can be
             expected to dominate sampling variance---especially with samples as
             large as the ones used in the U.S. Census Bureau's Post-Enumeration
             Surveys. These findings constrain the viable estimation strategies
             that could be employed for local tallies in the U.S. 2000 Census.},
   }

        

@article{WACHTER:2000:TFCCBI,
   AUTHOR = {Wachter, Kenneth W. and Freedman, David A.},
    TITLE = {The fifth cell: Correlation bias in U.S. census adjustment},
  JOURNAL = {Evaluation Review},
   VOLUME = {24},
     YEAR = {2000},
    PAGES = {191--212},
      URL = {http://erx.sagepub.com/cgi/content/abstract/24/2/191},
 ABSTRACT = {One form of error that can affect census adjustments is correlation
             bias, reflecting people who are doubly missing--from the census and
             from the adjusted counts as well. This article presents a method
             for estimating the total national number of doubly-missing people
             and their distribution by race and sex. Application to the 1990
             U.S. census adjustment leads to an estimate of 3 million doubly-
             missing people. Correlation bias is likely to be a serious problem
             for census adjustment in 2000. The methods of this article are well
             suited for measuring its magnitude.},
   }

        

@article{WACHTER:1999:GOMMIL:0938.62066,
   AUTHOR = {Wachter, K.W.},
    TITLE = {Grade of membership models in low dimensions: Geometry and
             robustness},
  JOURNAL = {Statistical Papers},
     ISSN = {0932-5026},
   VOLUME = {40},
     YEAR = {1999},
    PAGES = {439--457},
     NOTE = {October 1999},
ZBLABSTRACT = {Grade of Membership (GoM) Models have always been presented by
             their inventors as statistical applications of fuzzy set theory.
             This paper develops an alternative formulation, recasting GoM as a
             geometric dimensionality-reduction technique in terms of an
             underlying family of metrics, exposing a close relationship with
             Principal Components. The geometric viewpoint facilitates intuitive
             understanding and guides an investigation into the robustness of
             GoM estimates to violations of assumptions, with test cases drawn
             from the National Survey of Families and Households. Analysis is
             restricted to visualizable, low-dimensional cases with two pure
             types and 3 to 9 dichotomous variables, and to ``conditional'' GoM,
             the version more commonly used but less commonly studied. In these
             low-dimensional settings, I find GoM to be a successful technique
             for recovering an underlying gradient among individuals when such a
             gradient is actually present. GoM is only moderately sensitive to
             moderate violations in its assumptions. In the cases studied, GoM
             solutions turn out to be remarkably close to Principal Component
             solutions.},
 ZBLCLASS = {62H25;62H99;62P25},
       ID = {info:zbl/0938.62066},
   }

        

@article{BROWN:1999:SCIC,
   AUTHOR = {Brown, Lawrence D. and Eaton, Morris L. and Freedman, David A. and
             Klein, Stephen P. and Olshen, Richard A. and Wachter, Kenneth W.
             and Wells, Martin T. and Ylvisaker, Donald},
    TITLE = {Statistical controversies in census 2000},
  JOURNAL = {Jurimetrics Journal},
   VOLUME = {39},
     YEAR = {1999},
    PAGES = {347--375},
      URL = {http://www.stat.berkeley.edu/~census/537.pdf},
 ABSTRACT = {This paper discusses Census 2000, focusing on sampling techniques
             for adjustment. Experience with similar adjustment methods in 1980
             and 1990 suggests that the design for Census 2000 is quite risky.
             The use of sampling to obtain population counts for apportionment
             was rejected by the Supreme Court as violating the Census Act.
             Statistical adjustments for the purpose of redistricting may or may
             not be constitutional.},
   }

        

@article{WACHTER:1999:EDMFMP:10.1073/pnas.96.18.10544,
   AUTHOR = {Wachter, K.W.},
    TITLE = {Evolutionary demographic models for mortality plateaus},
  JOURNAL = {Proc. Natl. Acad. Sci. Unit. States Am.},
 FJOURNAL = {Proceedings of the National Academy of Sciences of the United
             States of America},
   VOLUME = {96},
   NUMBER = {18},
     YEAR = {1999},
    PAGES = {10544--10547},
       ID = {info:doi/10.1073/pnas.96.18.10544},
 ABSTRACT = {Plateaus in the age pattern of hazard functions at extreme ages
             have been discovered in large populations of medflies, Drosophila,
             nematodes, and people. Mueller and Rose [(1996) Proc. Natl. Acad.
             Sci. USA 93, 15249--15253] have proposed several age-structured
             demographic models to represent effects of mutation accumulation
             and antagonistic pleiotropy on randomly evolving schedules of
             demographic rates. They assert that \u201cevolutionary theory [as
             embodied in their models] predicts late-life mortality
             plateaus.\u201d This paper defines a class of Markovian models that
             includes those of Mueller and Rose and obtains a characterization
             of the possible limiting states. For the basic model, the result
             implies that schedules with late-life mortality plateaus above a
             minimal threshold are not limiting states. The models fail, but not
             for reasons previously conjectured. Transient states, visited early
             by the process, do display mortality plateaus. Other models from
             this class may have a role to play in reconciling observed plateaus
             with evolutionary theory.},
   }

        

@article{WACHTER:1997:KRFTE:10.1098/rstb.1997.0166,
   AUTHOR = {Wachter, K.W.},
    TITLE = {Kinship resources for the elderly},
  JOURNAL = {Phil. Trans. R. Soc. B},
     ISSN = {0962-8436, 1471-2970 (electronic)},
   VOLUME = {352},
   NUMBER = {1363},
     YEAR = {1997},
    PAGES = {1811--1817},
       ID = {info:doi/10.1098/rstb.1997.0166},
 ABSTRACT = {As population ageing strains social insurance systems, cohorts
             whose own fertility was low will be reaching elderly status,
             leaving close biological kin in short supply. However, there is a
             countervailing trend, inasmuch as burgeoning divorce, remarriage
             and family blending have expanded the numbers and varieties of
             step-kin and other non-standard kinship ties. Methods of computer
             microsimulation in conjunction with richer sample surveys can help
             us to foresee the contours of kin numbers and kinship relations in
             the future. Prime areas include the likely frequency of kin-
             deprived elderly, the overlap with economic deprivation and the
             interaction between kin frequency and intensity of contact. Step-
             ties may be weaker but nonetheless critical in raising the
             probability of at least one compatible member with whom one can
             choose to maintain contact and rely on. Kinship networks extended
             through half- and step-links, by stretching across racial and
             economic lines, may promote social cohesion.},
   }

        

@article{WACHTER:1997:TTVOKM,
   AUTHOR = {Wachter, Kenneth W. and Blackwell, Debra and Hammel, Eugene A.},
    TITLE = {Testing the validity of kinship microsimulation},
  JOURNAL = {Journal of Mathematical and Computer Modeling},
     ISSN = {0895-7177},
   VOLUME = {26},
   NUMBER = {6},
     YEAR = {1997},
    PAGES = {89--104},
ZBLABSTRACT = {Computer microsimulation is capable of generating detailed
             reconstructions and forecasts of the numbers of living kin that
             members of a population have. The available detail, specificity,
             and consistency of vital rates for the past and the accuracy of
             vital rates projected for the future necessarily limit the accuracy
             of the kinship estimates that can be produced.\par This study is an
             external validity test of {\it J. Reeves'} [A statistical analysis
             and projection of the effects of divorce on future U.S. kinship
             structure. Ph.D. Thesis, Univ. California/Berkeley (1982)]
             reconstruction and forecast of U.S. kin counts with the SOCSIM
             microsimulation program. The external standard is provided by
             estimates from the 1987-88 wave of the National Survey of Families
             and Households, the first detailed information on numbers and ages
             of kin for the United States. We compare forecasts with estimates
             for average numbers of living grandchildren, living full-siblings,
             and living half-siblings as functions of age. We find remarkably
             close agreement for some of the predictions, along with several
             instances of systematic discrepancies. The discrepancies most
             likely stem from errors in the forecasts rather than in the survey
             estimates. Interacting rather than isolable errors appear to be
             responsible. Our validity tests provide a basis for qualified faith
             in the effectiveness of kinship microsimulation.},
 ZBLCLASS = {91D20},
       ID = {info:zbl/0884.92034, info:doi/10.1016/S0895-7177(97)00172-6},
   }

        

@article{HAMMEL:1996:ETSCOP,
   AUTHOR = {Hammel, E.A. and Wachter, K.W.},
    TITLE = {Evaluating the {S}lavonian census of 1698: Part II: A
             microsimulation test and extension of the evidence},
  JOURNAL = {European Journal of Population},
   VOLUME = {12},
     YEAR = {1996},
    PAGES = {295--326},
       ID = {info:doi/10.1007/BF01796911},
 ABSTRACT = {An adjusted 17th C. census based on critical reading of the
             historical text is the basis for indirect estimation of uncounted
             persons. The census states no ages and excludes many categories of
             household residents. Microsimulation based on historically and
             ethnographically plausible rates and household formation scenarios
             produces simulated households that match the observable portions of
             households in the adjusted census. Microsimulation results permit
             estimation of the uncounted population, of the kinship and age
             composition of households under extant frontier conditions, and the
             probable future composition of households as the frontier
             stabilized and land shortage began to exert pressure for greater
             density and household complexity.},
   }