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Negative Exponential

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Journal Article
Demography (1969) 6 (1): 55–74.
Published: 01 February 1969
...-density gradient, empirically always negative. Expanding this exponential model permits examining systematically the relationship between distance from center and various components of population density—housing-unit density, vacant units, household size, and group-quarters population–and the change over...
Journal Article
Demography (1973) 10 (4): 537–542.
Published: 01 November 1973
... Population Constant Fertility Negative Exponential Fertility Schedule Mortality Schedule References Coale, Ansley J. 1959. Increases in Expectation of Life and Population Growth. In the Proceedings of the International Union for the Scientific Study of Population, Vienna, 1959. Lotka...
Journal Article
Demography (1972) 9 (1): 1–11.
Published: 01 February 1972
... Expectancy Retention Rate Actual Observation Cumulative Density Function Negative Exponential Function References Berkson J. , & Gage R. P. ( 1952 ). Survival curve for cancer patients following treatment . Journal of American Statistical Association , 47 , 501 – 515...
Journal Article
Demography (1987) 24 (4): 615–622.
Published: 01 November 1987
... called attention to it). It is said that H measures the concavity (Keyfitz, 1977a), convexity (Demetrius, 1979a,b), or rectangularity (Nagnur, 1986) of a survival curve. From a mathematical viewpoint, it has no necessary association with the life expectancy. In a negative exponential life table...
Journal Article
Demography (1977) 14 (1): 103–104.
Published: 01 February 1977
... density functions. if x:f. J.L, negative exponential with its origin at the observed value of Xa, say II) is UIIII) = X exp [-X(1-/I Now, the probability that a woman of group B ovulates in the interval (x, x + dx) and conceives in the interval (I, I + dl) is given by the product P(Xa = x) . P(X. = I), °S...
Journal Article
Demography (1983) 20 (3): 273–284.
Published: 01 August 1983
... are as- sumed to be negative exponential for residents and uniform for nonresidents. Additionally, the model assumes that these distributions are not influenced by natural growth and decay. Unfortunate- ly, the distributional assumptions of Manly's model are inappropriate for hu- man population groups and other...
Journal Article
Demography (2011) 48 (2): 425–436.
Published: 30 April 2011
... the United States. The simulation of the return migration rate over the migrant’s length of residence, based on the Reyes’ study, approximates a negative exponential function, with the highest rate of return occurring during the first year of residence, rapidly declining with each subsequent year...
Includes: Supplementary data
Journal Article
Demography (1986) 23 (1): 105–126.
Published: 01 February 1986
... N.S. , 1 , 275 – 295 . 10.1090/S0273-0979-1979-14594-4 Cohen J. E. ( 1979 ). Contractive inhomogeneous products of non-negative matrices . Mathematical Proceedings of the Cambridge Philosophical Society , 86 , 351 – 364 . 10.1017/S0305004100056176 Cohen J. E. ( 1979...
Journal Article
Demography (1991) 28 (2): 261–274.
Published: 01 May 1991
...Stanley K. Smith; Terry Sincich Abstract Many studies have found that population forecast errors generally increase with the length of the forecast horizon, but none have examined this relationship in detail. Do errors grow linearly, exponentially, or in some other manner as the forecast horizon...
Journal Article
Demography (1965) 2 (1): 429–443.
Published: 01 March 1965
...;« (or Mob) is positive for natural increase but negative for net migration; and Dim (or Mid) is negative for natural increase but positive for net migration. So, although Ie.; - DimImay be an important component of both natu- ral increase and net migration, it con- tributes absolutely nothing to the total...
Journal Article
Demography (1989) 26 (2): 185–201.
Published: 01 May 1989
... ). London : International Statistical Institute . Owasu , J. ( 1984 ). Evaluation of the Ghana Fertility Survey, 1979–1980 . Voorburg, The Netherlands : International Statistical Institute . Pittinger , D. B. ( 1973 ). An exponential model of female sterility . Demography , 10...
Journal Article
Demography (1976) 13 (4): 571–575.
Published: 01 November 1976
...Linton C. Freeman; Morris H. Sunshine Abstract Data from the urban renewal experience in Syracuse, New York are used to examine the impact of race on patterns of intra-urban migration. The results show that, overall, the migration patterns exhibited an exponential decay in frequency with increasing...
Journal Article
Demography (1989) 26 (3): 373–391.
Published: 01 August 1989
... areas, defined here as a negative exponential: Cii = exp(- d ii). The term di; indicates the linear distance between the centroids of units i and i. and d ii is estimated as 0.6ai X 5, where c, is the area of the tract. The negative exponential assumes that the likelihood of intragroup inter- action...
Journal Article
Demography (1967) 4 (2): 773–779.
Published: 01 June 1967
... variables. Linear associations were found for four economic variables, and a curvilinear association in the form of a J curve for four demographic variables. It was found that the exponential distribution y = e −X for the curves for the demographic variables (crude birth rate, infant mortality rate, percent...
Journal Article
Demography (1970) 7 (1): 93–120.
Published: 01 February 1970
... repetitive cycle, age composition must also be repetitive with the same cycle length. Under these conditions annual births follow a path that is an exponential multiplied by a periodic time-function. If the time variation of fertility is a small amplitude sinusoidal oscillation, the periodic component...
Journal Article
Demography (2015) 52 (4): 1121–1146.
Published: 29 July 2015
... absence, particularly parental death. With some exceptions (Deininger et al. 2003 ; Lindblade et al. 2003 ), the literature finds negative consequences of orphanhood across a variety of domains. Orphans have higher morbidity (Ainsworth and Semali 2000 ; Birdthistle et al. 2008 ), higher mortality...
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Journal Article
Demography (1994) 31 (3): 403–426.
Published: 01 August 1994
... with this waiting-time distribution is a simple negative exponential; if fecundability does vary, the survival function drops off more rapidly at early exposures as high-fecundability couples conceive, but then bottoms out as the remaining sample becomes selected increasingly for low fecundability. Heterogeneous...
Journal Article
Demography (2019) 56 (3): 1075–1103.
Published: 18 March 2019
... generation status in a large, diverse sample of 7th through 12th graders from the National Longitudinal Study of Adolescent to Adult Health ( n = 67,586). Next, I test whether having a higher proportion of same-generation friends can protect immigrant youth from experiencing negative health outcomes...
Includes: Supplementary data
Journal Article
Demography (1986) 23 (1): 137–139.
Published: 01 February 1986
... in the late 1960s, and renewed slippage throughout the 1970s. The Devaney relative income, measured by deviations from an exponential trend line for lifetime income, produces a pattern of continuous slippage beginning somewhat earlier-in fairness to Easterlin perhaps too early. One can speculate...
Journal Article
Demography (2003) 40 (2): 351–367.
Published: 01 May 2003
.... A negative answer would suggest a marked differentiation, at least behaviorally, between marriage and cohabitation. Extending the earlier work of Thornton et al. (1995), this article contributes to the literature on union formation in two important ways. First, our study considers the role of economic...