arXiv subjects

Bertrand M. Roehner

Publications and source records attributed to Bertrand M. Roehner.

At least 37 records · Page 2Linked to original sources

arXiv2017

Spatial and historical determinants of separatism and integration. 1. Qualitative analysis

Separatism is examined in a long-run perspective. Accordingly, many political or economic factors which may be crucial in dealing with short-term episodes can be safely disregarded. Extending an approach pioneered by J. Jenkins, the paper assesses the role of spatial and historical factors. It shows that the means used to stage a separatist struggle are to a notable extent borrowed from former historical episodes, an analysis which supports and illustrates Charles Tilly's thesis of restricted repertoires of action. The purpose of the present paper is to introduce the model, to make it plausible and to demonstrate its potential usefulness by examining a number of critical examples. A more systematic analysis is carried out in a follow-up paper by using a data set that includes about 40 cases of separatist struggles.

physics.soc-ph↗

arXiv2017

Spatial and historical determinants of separatism and integration. 2. Quantitative analysis

In part 1 we have discussed the role played by geographical and historical conditions. Here we wish to test our model and to estimate its parameters. Ti this effect two indexes are introduced. The geographical index is aimed at characterizing the degree of separateness of a given region with respect to the national state to which it belongs. This index turns out to be closely connected to the number of minority-speakers; it is also correlated with the level of separatist disturbances, at least for samples having the same historical background. The purpose of the second index is precisely to specify the role of past episodes in shaping current separatist outbreaks. To a large extent, current episodes are modeled on former ones; typically this process of semi-replication appears to be characterized by a "memory" that extends over at least one and a half century. Note that this study concentrates on the occurrence and forms of separatist struggles rather than on their short-term political causes. In so doing, it follows a methodological track that has been pioneered by Stanley Lieberson (1985, the "stardom" paradigm) and Charles Tilly (1993, the "traffic jam" paradigm).

physics.soc-ph↗

arXiv2017

Exploration of the strength of family links

Ever since the studies of Louis-Adolphe Bertillon in the late 19th century it has been known that marital status and number of children markedly affect death and suicide rates. This led in 1898 Emile Durkheim to conjecture a connection between social isolation (especially at family level) and suicide. However, further progress was long hampered by the limited statistical data available from death certificates. Recently, it was shown by the present authors that disability data from census records can be used as a reliable substitute for mortality data. This opens a new route to investigations of family ties because census information goes much beyond the limited data reported on death certificates. It is shown that the disability rate of adults decreases when they have more family links. More precisely, the reduction of the parents' disability brought about by the presence of a child reveals that the strength of ties between parents and child is highest in the first year after birth and then weakens steadily as the child ages. It will also be seen that the strength of the bond between husband and wife is highest when they are of same age and decreases fairly steadily when the age gap increases.

physics.soc-ph↗

arXiv2017

Impact of marital status on health

The Farr-Bertillon law states that the mortality rate of single and widowed persons is about three times the rate of married people of same age. This excess mortality can be measured with good accuracy for all ages except for young widowers. The reason is that, at least nowadays, very few people become widowed under the age of 30. Here we show that disability data from census records can also be used as a reliable substitute for mortality rates. In fact excess-disability and excess-mortality go hand in hand. Moreover, as there are about ten times more cases of disability than deaths, the disability variable is able to offer more accurate measurements in all cases where the number of deaths is small. This allows a more accurate investigation of the young widower effect; it confirms that, as already suspected from death rate data, there is a huge spike between the ages of 20 and 30. By using disability rates we can also study additional features not accessible using death rate data. For example we can examine the health impact of a change in living place. The observed temporary inflated disability rate confirms what could be expected by invoking the "Transient Shock" conjecture formulated by the authors in a previous paper.

physics.soc-ph↗

arXiv2017

Analytical history

The purpose of this note is to explain what is "analytical history", a modular and testable analysis of historical events introduced in a book published in 2002 (Roehner and Syme 2002). Broadly speaking, it is a comparative methodology for the analysis of historical events. Comparison is the keystone and hallmark of science. For instance, the extrasolar planets are crucial for understanding our own solar system. Until their discovery, astronomers could observe only one instance. Single instances can be described but they cannot be understood in a testable way. In other words, if one accepts that, as many historians say, "historical events are unique", then no testable understanding can be developed.

physics.hist-ph↗

arXiv2016

Phenomenology of infant death rates. Identification of the peaks of viral and bacterial diseases

After birth setting up an effective immune system is a major challenge for all living organisms. In this paper we show that this process can be explored by using the age-specific infant death rate as a kind of sensor. This is made possible because, as shown by the authors in Berrut et al. (2016), between birth and a critical age t_c, for all mammals the death rate decreases with age as an hyperbolic function. For humans t_c is equal to 10 years. At some ages the hyperbolic fall displays spikes which, it is assumed, correspond to specific events in the organism's response to exogenous factors. One of these spikes occurs 10 days after birth and there is another at the age of about 300 days. It is shown that the first spike is related to viral infections whereas the second is related to bacterial diseases. By going back to former time periods during which infant mortality was much higher than currently, it is possible to get a magnified view of these peaks which in turn may give us useful information about how an organism adapts to new conditions. Apart from pathogens, the same methodology can be used to study the response to changes in other external conditions, e.g. supply of food, temperature or oxygen level.

physics.med-ph↗

arXiv2016

Is cancer a disease that can be cured? An answer based on a new classification of diseases

Is cancer a disease that can be cured or a degenerative disease which comes predominantly with old age? We give an answer based on a two-dimensional representation of diseases. These two dimensions are defined as follows. In mortality curves there is an age, namely a_c = 10 years, which plays a crucial role in the sense that the mortality rate decreases in the interval I1=(a a_c). The respective trends in I1 and I2 are the two parameters used in our classification of diseases. Within the framework of reliability analysis, I1 and I2 would be referred to as the "burn-in" and "wear-out" phases. This leads to define three broad groups of diseases. (AS1) Asymmetry with prevalence of I1. (AS2) Asymmetry with prevalence of I2. (S) Symmetry, with I1 and I2 both playing roles of comparable importance. Not surprisingly, among AS1-cases one finds all diseases due to congenital malformations. In the AS2-class one finds degenerative diseases, e.g. Alzheimer's disease. Among S-cases one finds most diseases due to external pathogens or to wear-out processes. Cancer is one of those mixed cases and it is closer to (AS2) than to (AS1). This representation also explains what we call an OVERKILL EFFECT in old age. It tells us that even an effective cancer therapy would have no influence whatsoever on the extent of human life unless ALL other diseases are cured simultaneously. We conclude that whilst one might develop a cure for many of the known diseases of old age, new diseases will arise and the quest for the ultimate cure will be never ending. Death before the age of 120 seems firmly written in our genetic code and the best we shall be able to do is to help people cope with the inevitability of death as and when it arises.

physics.med-ph↗

arXiv2016

Property bubble in Hong Kong: A predicted decade-long slump (2016-2025)

Between 2003 and 2015 the prices of apartments in Hong Kong (adjusted for inflation) increased by a factor of 3.8. This is much higher than in the United States prior to the so-called subprime crisis of 2007. The analysis of this speculative episode confirms the mechanism and regularities already highlighted by the present authors in similar episodes in other countries. Based on these regularities, it is possible to predict the price trajectory over the time interval 2016-2025. It suggests that, unless appropriate relief is provided by the mainland, Hong Kong will experience a decade-long slump. Possible implications for its relations with Beijing are discussed at the end of the paper.

q-fin.GN↗

arXiv2016

The wage transition in developed countries and its implications for China

The expression "wage transition" refers to the fact that over the past two or three decades in all developed economies wage increases have levelled off. There has been a widening divergence and decoupling between wages on the one hand and GDP per capita on the other hand. Yet, in China wages and GDP per capita climbed in sync (at least up to now). In the first part of the paper we present comparative statistical evidence which measures the extent of the wage transition effect. In a second part we consider the reasons of this phenomenon, in particular we explain how the transfers of labor from low productivity sectors (such as agriculture) to high productivity sectors (such as manufacturing) are the driver of productivity growth, particularly through their synergetic effects. Although rural flight represents only one of these effects, it is certainly the most visible because of the geographical relocation that it implies; it is also the most well-defined statistically. Moreover, it will be seen that it is a good indicator of the overall productivity and attractivity of the non-agricultural sector. Because this model accounts fairly well for the observed evolution in industrialized countries, we use it to predict the rate of Chinese economic growth in the coming decades. Our forecast for the average annual growth of real wages ranges from 4% to 6% depending on how well China will control the development of its healthcare industry.

q-fin.GN↗

arXiv2016

Deciphering infant mortality. Part 1: empirical evidence

This paper is not (or at least not only) about human infant mortality. In line with reliability theory, "infant" will refer here to the time interval following birth during which the mortality (or failure) rate decreases. This definition provides a systems science perspective in which birth constitutes a sudden transition which falls within the field of application of the "Transient Shock" (TS) conjecture put forward in Richmond et al. (2016c). This conjecture provides predictions about the timing and shape of the death rate peak. (i) It says that there will be a death rate spike whenever external conditions change abruptly and drastically. (ii) It predicts that after a steep rising there will be a much longer hyperbolic relaxation process. These predictions can be tested by considering living organisms for which birth is a multi-step process. Thus, for fish there are three states: egg, yolk-sac phase, young adult. The TS conjecture predicts a mortality spike at the end of the yolk-sac phase, and this timing is indeed confirmed by observation. Secondly, the hyperbolic nature of the relaxation process can be tested using high accuracy Swiss statistics which give postnatal death rates from one hour after birth up to the age of 10 years. It turns out that since the 19th century despite a great overall reduction in infant mortality, the shape of the age-specific death rate has remained basically unchanged. This hyperbolic pattern is not specific to humans. It can also be found in small primates as recorded in the archives of zoological gardens. Our ultimate objective is to set up a chain of cases which starts from simple systems and then moves up step by step to more complex organisms. The cases discussed here can be seen as initial landmarks.

q-bio.PE↗

arXiv2015

Predictive implications of Gompertz's law

Gompertz's law tells us that for humans above the age of 35 the death rate increases exponentially with a doubling time of about 10 years. Here, we show that the same law continues to hold even for ages over 100. Beyond 106 there is so far no statistical evidence available because the number of survivors is too small even in the largest nations. However assuming that Gompertz's law continues to hold beyond 106, we conclude that the mortality rate becomes equal to 1 at age 120 (meaning that there are 1,000 deaths in a population of one thousand). In other words, the upper bound of human life is near 120. The existence of this fixed-point has interesting implications. It allows us to predict the form of the relationship between death rates at age 35 and the doubling time of Gompertz's law. In order to test this prediction, we first carry out a transversal analysis for a sample of countries comprising both industrialized and developing nations. As further confirmation, we also develop a longitudinal analysis using historical data over a time period of almost two centuries. Another prediction arising from this fixed-point model, is that, above a given population threshold, the lifespan of the oldest person is independent of the size of her national community. This prediction is supported by available empirical evidence.

physics.soc-ph↗

arXiv2015

Effect of marital status on death rates. Part 1: High accuracy exploration of the Farr-Bertillon effect

The Farr-Bertillon law says that for all age-groups the death rate of married people is lower than the death rate of people who are not married (i.e. single, widowed or divorced). Although this law has been known for over 150 years, it has never been established with great accuracy. This even let some authors argue that it was a statistical artefact. It is true that the data must be selected and analyzed with great care, especially for age groups of small size such as widowers under 25. The observations reported in this paper were selected and designed in the same way as experiments in physics, that is to say with the objective of minimizing the error bars for all age-groups. It will be seen that data appropriate for mid-age groups may be unsuitable for young age groups and vice versa. The investigation led to the following results. (1) The FB effect is basically the same for men and women, except that on average it is about 20\% stronger for men. (2) There is a marked difference between single or divorced persons on the one hand, for whom the effect is largest around the age of 45, and widowed persons on the other hand, for whom the effect is largest around the age of 25. (3) When different causes of death are distinguished, the effect is largest for suicide and smallest for cancer. (4) For young widowers the death rates are up to 10 times higher than for married persons of same age. This extreme form of the FB effect will be referred to as the "young widower effect." A possible connection between the FB effect and Martin Raff's "Stay alive" effect for cells in an organism is discussed in the last section.

physics.soc-ph↗

arXiv2015

Effect of marital status on death rates. Part 2: Transient mortality spikes

We examine what happens in a population when it experiences an abrupt change in surrounding conditions. Several cases of such "abrupt transitions" for both physical and living social systems are analyzed from which it can be seen that all share a common pattern. First, a steep rising death rate followed by a much slower relaxation process during which the death rate decreases as a power law (with an exponent close to 0.7). This leads us to propose a general principle which can be summarized as follows: "ANY abrupt change in living conditions generates a mortality spike which acts as a kind of selection process." This we term the Transient Shock conjecture. It provides a qualitative model which leads to testable predictions. For example, marriage certainly brings about a major change in environmental and social conditions and according to our conjecture one would expect a mortality spike in the months following marriage. At first sight this may seem an unlikely proposition but we demonstrate (by three different methods) that even here the existence of mortality spikes is supported by solid empirical evidence.

physics.soc-ph↗

arXiv2015

The detection of cheating in multiple choice examinations

Cheating in examinations is acknowledged by an increasing number of organizations to be widespread. We examine two different approaches to assess their effectiveness at detecting anomalous results, suggestive of collusion, using data taken from a number of multiple-choice examinations organized by the UK Radio Communication Foundation. Analysis of student pair overlaps of correct answers is shown to give results consistent with more orthodox statistical correlations for which confidence limits as opposed to the less familiar "Bonferroni method" can be used. A simulation approach is also developed which confirms the interpretation of the empirical approach.

physics.soc-ph↗

arXiv2014

How can one explain changes in the monthly pattern of suicide?

The monthly pattern of suicides has remained a puzzle ever since it was discovered in the second half of the 19th century. In this paper we intend to "explain" not the pattern itself but rather its changes across countries and in the course of time. First, we show that the fairly common idea according to which this pattern is decaying in "modern" societies is not altogether true. For instance, around 2000, in well urbanized countries like South Korea or Spain this pattern was still as strong as it was in France (and other European countries) in the late 19th century. The method that we use in order to make some progress in our understanding is the time-honoured Cartesian approach of breaking up the problem under consideration "into as many parts as might be necessary to solve it". More specifically, we try two decompositions of monthly suicides: (i) according to suicide methods (ii) according to age-groups. The first decomposition points out the key-role of hanging and drowning. The second shows the crucial role of the $ 15-20 $ and $ 65+ $ age-groups. Then, we present a number of cases in which age-group decomposition provides adequate predictions. It turns out that the cases in which the predictions do not work are newly urbanized countries. The discrepancies may be due to a memory effect which induces a time-lag extending over one or two generations. Finally, in the light of the new results presented in the present paper, we re-examine the theory proposed by Emile Durkheim.

physics.soc-ph↗

arXiv2014

Is the month of Ramadan marked by a reduction in the number of suicides?

For Muslims the month of Ramadan is a time of fasting but during the evenings after sunset it is also an occasion for family and social gatherings. Therefore, according to the Bertillon-Durkheim conception of suicide (that is based on the strength of social ties), one would expect a fall in suicide rates during Ramadan. Is this conjecture confirmed by observation? That is the question addressed in the present paper. Surprisingly, the most tricky part of the investigation was to find reliable monthly suicide data. In the Islamic world Turkey seems to be the only country whose statistical institute publishes such observations. The data reveal indeed a fall of about $15\%$ in suicide numbers during the month of Ramadan (with respect to same-non-Ramadan months). As the standard deviation is only $4.7\%$ this effect has a high degree of significance. This observation, along with the fact that other occasions of social gathering such as Thanksgiving or Christmas are also marked by a drop in suicides, adds further credence to the B-D thesis.

physics.soc-ph↗

arXiv2013

How are mortality rates affected by population density?

Biologists have found that the death rate of cells in culture depends upon their spatial density. Permanent "Stay alive" signals from their neighbours seem to prevent them from dying. In a previous paper (Wang et al. 2013) we gave evidence for a density effect for ants. In this paper we examine whether there is a similar effect in human demography. We find that although there is no observable relationship between population density and overall death rates, there is a clear relationship between density and the death rates of young age-groups. Basically their death rates decrease with increasing density. However, this relationship breaks down around 300 inhabitants per square kilometre. Above this threshold the death rates remains fairly constant. The same density effect is observed in Canada, France, Japan and the United States. We also observe a striking parallel between the density effect and the so-called marital status effect in the sense that they both lead to higher suicide rates and are both enhanced for younger age-groups. However, it should be noted that the strength of the density effect is only a fraction of the strength of the marital status effect. In spite of the fact that this parallel does not give us an explanation by itself, it invites us to focus on explanations that apply to both effects. In this light the "Stay alive" paradigm set forth by Prof. Martin Raff appears as a natural interpretation. It can be seen as an extension of the "social ties" framework proposed at the end of the 19th century by the sociologist Emile Durkheim in his study about suicide.

physics.soc-ph↗

arXiv2013

How can one detect the rotation of the Earth "around the Moon"? Part 3. With a simple pendulum

The attraction of the Moon on objects at the surface of the Earth gives rise to a so-called tidal force which is of the order of 1/10,000,000 times the gravitational force of the Earth. For instance, when the Moon is located between the Earth and the Sun (new moon) the distance from a given terrestrial location to the Moon is shorter at noon than at midnight. This reduces the gravitational acceleration and therefore increases the period of a simple pendulum by a small amount. Although the change is of the order of 100 nanoseconds it appears that it can be detected. We give some preliminary results and discuss how the accuracy can be further improved. It is hoped that the present paper will encourage new experiments in this direction.

physics.class-ph↗