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Media coverage of suicide can influence population suicide rates. While reports of suicide deaths are often associated with increased suicides (Werther effect), stories of survival may be associated with reductions (Papageno effect). On 11 September 2024, news outlets widely reported musician Jon Bon Jovi intervening to stop a woman’s suicide attempt in Tennessee.
Aims
To assess whether this highly publicised intervention was associated with contemporaneous reductions in suicide deaths in Tennessee and 19 comparison states.
Method
We conducted quasi-Poisson time-series analyses of monthly suicide deaths from 2014 to 2024, adjusting for macroeconomic indicators and seasonality. To ensure geographic and temporal specificity, we employed a two-stage validation framework including temporal placebo testing (116 iterations) and comparison across 19 states (60 subgroups, by total and gender) using Benjamini–Hochberg false discovery rate (FDR) correction.
Results
In Tennessee, a significant reduction in suicide mortality occurred in September 2024 (risk ratio 0.78; percentile: 0.9%). The effect was most robust among Tennessean males (risk ratio 0.74), at the 0.9th percentile of the historical distribution. This was the only subgroup among 60 examined to maintain statistical significance after FDR adjustment (p < 0.001). No significant deviation was observed among Tennessean females or within comparison states after multiple testing corrections.
Conclusions
This study provides the first evidence of a Papageno effect following a widely publicised, real-life survival story. The localised impact suggests a local exposure and/or resonance factor, while the male-specific reduction may reflect identification with the male intervener (i.e. Bon Jovi). Survival narratives may represent an underutilised opportunity for suicide prevention and warrant further study and should be integrated into responsible media reporting guidelines.
The development and implementation of national suicide prevention strategies (NSPSs) is one policy response to suicide prevention adopted by the World Health Organization (WHO); however, evidence on their effectiveness remains limited and mixed. This study assessed the impact of implementing an NSPS on sex-specific suicide mortality rates in nine countries within the Region of the Americas from 2000 to 2021. Suicide rates were obtained from the WHO Global Health Estimates, and countries with an NSPS and the year it was first implemented were identified using the WHO MiNDbank. A comparative interrupted time-series analysis using linear mixed-effects models was conducted to estimate the effect of NSPS implementation on suicide mortality. The implementation of an NSPS was associated with a gradual and sustained decrease in suicide mortality rates: 3.00% per year among males (95% CI: −5.28%, −0.66%) and 2.55% per year among females (95% CI: −4.62%, −0.44%). No significant difference in effect was observed between sexes. These findings demonstrate an association between NSPS and reduced suicide mortality in countries within the region, emphasizing the value of their ongoing development and implementation. Although the association did not vary by sex, NSPS design should account for sex-specific epidemiological contexts.
This chapter provides an overview of different types of research, aiming to provide a comprehensive framework for understanding the various ways research types can be conceptualized. You will learn the key characteristics and features of each research type, and understand the differences between positivist, postpositivist, and interpretivist research, including their advantages and limitations. Additionally, you will learn about the key differences between quantitative, qualitative, and mixed methods research methodologies, as well as their respective strengths and weaknesses. The chapter also defines the main types of research designs – experimental, correlational, and descriptive – highlighting their strengths and weaknesses, and clarifies the distinctions between basic and applied research. It will also explore the differences between cross-sectional, longitudinal, and time-series research designs. By the end of this chapter, you will appreciate the different types of research available to you, which will help you identify the most appropriate research type for your research questions and objectives.
Fish swimming together in schools interact via multiple sensory pathways, including vision, acoustics and hydrodynamics, to coordinate their movements. Disentangling the specific role of each sensory pathway is an open and important question. Here, we propose an information-theoretic approach to dissect interactions between swimming fish based on their movement and the flow velocity at selected measurement points in the environment. We test the approach in a controlled mechanical system constituted by an actively pitching airfoil and a compliant flag that simulates the behaviour of two fish swimming in line. The system consists of two distinct types of interactions – hydrodynamic and electromechanical. By using transfer entropy of the measured time series, we unveil a strong causal influence of the airfoil pitching on the flag undulation with an accurate estimate of the time delay between the two. By conditioning the computation on the flow-speed information, recorded by laser Doppler velocimetry, we discover a significant reduction in transfer entropy, correctly implying the presence of a hydrodynamic pathway of interaction. Similarly, the electromechanical pathway of interaction is identified accurately when present. The study supports the potential use of information-theoretic methods to decipher the existence of different pathways of interaction between schooling fish.
Focused on empirical methods and their applications to corporate finance, this innovative text equips students with the knowledge to analyse and critically evaluate quantitative research methods in corporate finance, and conduct computer-aided statistical analyses on various types of datasets. Chapters demonstrate the application of basic econometric models in corporate finance (as opposed to derivations or theorems), backed up by relevant research. Alongside practical examples and mini case studies, computer lab exercises enable students to apply the theories of corporate finance and make stronger connections between theory and practice, while developing their programming skills. All of the Stata code is provided (with corresponding Python and R code available online), so students of all programming abilities can focus on understanding and interpreting the analyses.
A time series contains the values of a dataset sampled at different points in time. Some examples in financial research include asset prices, volatility indices, inflation rates, revenues, and so on. This chapter briefly covers the basic methods used in time-series analysis. Issues include whether the time-series data have equally spaced intervals, whether there is noise or error, how quickly the series grows, and whether the series has missing values. The chapter begins by testing for autocorrelation and remedies for autocorrelation. It then presents some standard tests for stationarity and cointegration, briefly covering random walks and the unit-root test. The models covered, among others, include autoregressive distributed lag (ARDL), autoregressive moving average (ARMA), autoregressive integrated moving average (ARIMA), generalized autoregressive conditional heteroskedasticity (GARCH), and vector autoregressive (VAR) models. The chapter provides an application to mortgage rates and ends with lab work and a mini case study.
Prior studies report a decline in male twin live births during economically stressful periods, presumably owing to higher selection in utero against frail male gestations, yet no study has examined the natural corollary: whether provision of economic support increases rates of male twin births. We examined whether male twin live births increase following income gains from the Alaska Permanent Fund Dividend (PFD)—the longest running unconditional cash transfer program in the US. We obtained the monthly volume of male (and female) twin and singleton live births, from January 1980 to December 2019, from Alaska’s Department of Health. Data on PFD timing and payment amounts came from Alaska’s Department of Revenue. We used time-series analyses to gauge whether the odds of male twin live births increase within 2−6 months following PFD receipt, controlling for autocorrelation. Results suggest that for every $1000 increase in PFD payments, the odds of male twin live births increase by 0.002 (p < .05) three months following PFD disbursement. This corresponds with 50 additional (individual) male twin live births statistically attributable to the cumulative PFD amount disbursed over our study period. Income gains through the PFD may correspond with reduced male-specific selection in utero in Alaska.
This study investigates the impacts of behavioral finance on stock market volatility. The primary aims are to explain the reasons behind changes in the S&P 500 price within the context of behavioral finance and to analyze investor behavior in response to these changes. To achieve this, the research employs time-series analysis over a 10-year period, focusing on the S&P 500, real interest rates, consumer confidence, market volatility and credit default swaps while considering the effects of behavioral biases. The findings reveal several significant correlations: rising real interest rates negatively affect stocks due to loss aversion and sentiment. Conversely, higher consumer confidence tends to positively influence the stock market, driven by herding behavior and optimism. Additionally, market volatility shows a negative correlation with the S&P 500, influenced by risk aversion, recency bias and herding behavior. Moreover, an increase in credit default swap rates leads to stock market declines, primarily influenced by risk perception, loss aversion and herding behavior.
This chapter studies the dynamics of elite support, which varies considerably across time. This temporal fluctuations are explained by three different sets of variables: the changing political and problem pressure that governments face, the contextual characteristics that may moderate this relationship, and the endogenous dynamics unfolding between different elite groups. Far from the elite closing ranks behind government proposals as the “rally-around-the-flag” perspective may suggest, nongovernment elites rather use the strategic opportunity offered by mounting problem pressure to articulate opposition to these proposals and signal distance from governments as a result. This dynamic is mostly confined to destination and transit states, and it is more prominent during debates on border controls and in the early phase of the crisis. By contrast, the impact of political pressure is largely in line with our expectations: In response to the growing strength of the radical right, the elite steps up dissent, with the strongest effect found, again, in destination states. In addition to responding to external pressure, elite groups were also shown to engage in strategic behavior with respect to each other.
Prior research based on Swedish data suggests that collective optimism, as measured by monthly incidence of suicides, correlates inversely with selection in utero against male twins in a population. We test this finding in the US, which reports the highest suicide rate of all high-income countries, and examine whether monthly changes in overall suicides precede changes in the ratio of male twin to male singleton live births. Consistent with prior work, we also examine as a key independent variable, suicides among women aged 15−49 years. We retrieved monthly data on suicides and the ratio of male twin to singleton live births from CDC WONDER, 2003 to 2019, and applied Box-Jenkins iterative time-series routines to detect and remove autocorrelation from both series. Results indicate that a 1% increase in monthly change in overall suicides precedes a 0.005 unit decline in male twin live births ratio 6 months later (coefficient = −.005, p value = .004). Results remain robust to use of suicides among reproductive-aged women as the independent variable (coefficient = −.0012, p value = .014). Our study lends external validity to prior research and supports the notion that a decline in collective optimism corresponds with greater selection in utero.
The aim of the present article is to evaluate the use of the Autoregressive Fractionally Integrated Moving Average (ARFIMA) model in predicting spatially and temporally localized political violent events using the Integrated Crisis Early Warning System (ICEWS). The performance of the ARFIMA model is compared to that of a naïve model in reference to two common relevant hypotheses: the ARFIMA model would outperform a naïve model and the rate of outperformance would deteriorate the higher the level of spatial aggregation. This analytical strategy is used to predict political violent events in Afghanistan. The analysis consists of three parts. The first is a replication of Yonamine’s study for the period beginning in April 2010 and ending in March 2012. The second part compares the results to those of Yonamine. The comparison was used to assess the validity of the conclusions drawn in the original study, which was based on the Global Database of Events, Language, and Tone, for the implementation of this approach to ICEWS data. Building on the conclusions of this comparison, the third part uses Yonamine’s approach to predict violent events in Afghanistan over a significantly longer period of time (January 1995–August 2021). The conclusions provide an assessment of the utility of short-term localized forecasting.
A large literature examines how citizens in violent conflicts react to the conflict's events, particularly violent escalations. Nevertheless, the temporal nature of these attitudinal changes remains under-studied. We suggest that popular reactions to greater violence are typically immediate but brief, indicating short-term emotional responses to physical threats. Over the longer term, however, public opinion is more commonly shaped by non-violent events signaling the adversary's perceived intentions, reflecting slower but deeper belief-updating processes. We support this argument using dynamic analyses of comprehensive monthly data from Israel spanning two full decades (2001–20). Rather than violence levels, we find that long-term changes in Jewish attitudes on the Israeli–Palestinian conflict follow non-violent events implying Palestinian preferences, particularly failed negotiations and out-group leadership changes. Our findings underscore the importance of public opinion's temporal dynamics and show that non-violent events, which are often overlooked in the literature, play a prominent role in shaping long-term attitudes in conflictual contexts.
In this article, we argue that rising housing prices increase voter approval of incumbent governments because such a rise increases personal wealth, which leads to greater voter satisfaction. This effect is strongest under right-wing governments because those who benefit from rising prices—homeowners—are more likely to be right-leaning. Non-homeowners, who are more likely to vote for left-leaning parties, will view rising housing prices as a disadvantage and therefore feel the government does not serve them well, which will mitigate the advantage to left-wing governments. We find support for our arguments using both macro-level data (housing prices and government approval ratings in 16 industrialized countries between 1960 and 2017) and micro-level data (housing prices and individuals’ vote choices in the United Kingdom using the British Household Panel Survey). The findings imply that housing booms benefit incumbent governments generally and right-wing ones in particular.
This chapter provides support for my main hypotheses that more urban and food-importing autocracies should be more likely to default, whereas more rural and food-exporting democracies should be more likely to renege on their international financial obligations.Drawing on approximately 50 years of cross-national data, I demonstrate robust evidence in favor of my main theoretical expectations, which remain even after introducing an extensive battery of controls for additional country- and systemic-level alternative explanations.In addition, I show that, for the subset of countries with relevant data on subsidy costs, it is precisely the most rural-biased democracies, and most urban-biased autocracies, that are most likely to default on their debt.
The Lung Cam expanded stratigraphic succession in Vietnam is correlated herein to the Meishan D section in China, the GSSP for the Permian–Triassic boundary. The first appearance datum of the conodont Hindeodus parvus at Meishan defines the Permian–Triassic boundary, and using published graphic correlation, the Permian–Triassic boundary level has been projected into the Lung Cam section. Using time-series analysis of magnetic susceptibility (χ) data, it is determined that H. parvus arrived at Lung Cam ∼18 kyr before the Permian–Triassic boundary. Data indicate that the Lung Cam section is expanded by ∼90 % relative to the GSSP section at Meishan. Given the expanded Lung Cam section, it is possible to resolve the timing of significant events during the Permian–Triassic transition with high precision. These events include major stepped extinctions, beginning at ∼135 kyr and ending at ∼110 kyr below the Permian–Triassic boundary, with a duration of ∼25 kyr, followed by deposition of Lung Cam ash Bed + 13, which is equivalent to Siberian Traps volcanism is graphically correlated to a precession Time-series model, placing onset of this major volcanic event at ~242 kyr before the PTB. The Meishan Beds 25 and 26, at ∼100 kyr before the Permian–Triassic boundary. In addition, the elemental geochemical, carbon and oxygen isotope stratigraphy, and magnetostratigraphy susceptibility datasets from Lung Cam allow good correlation to other Permian–Triassic boundary succession. These datasets are helpful when the conodont biostratigraphy is poorly known in sections with problems such as lithofacies variability, or is undefined, owing possibly to lithofacies exclusions, anoxia or for other reasons. The Lung Pu Permian–Triassic boundary section, ∼45 km from Lung Cam, is used to test these problems.
Time-series analysis is used to identify and quantify periodic features in datasets and has many applications across the geosciences, from analysing weather data, to solid-Earth geophysical modelling. This intuitive introduction provides a practical 'how-to' guide to basic Fourier theory, with a particular focus on Earth system applications. The book starts with a discussion of statistical correlation, before introducing Fourier series and building to the fast Fourier transform (FFT) and related periodogram techniques. The theory is illustrated with numerous worked examples using R datasets, from Milankovitch orbital-forcing cycles to tidal harmonics and exoplanet orbital periods. These examples highlight the key concepts and encourage readers to investigate more advanced time-series techniques. The book concludes with a consideration of statistical effect size and significance. This useful book is ideal for graduate students and researchers in the Earth system sciences who are looking for an accessible introduction to time-series analysis.
A new data analysis toolkit which is suitable for the analysis of large-scale, long-term datasets and the phenomenon/anomalies they represent is described. The toolkit aims to expose and quantify scientific information in a number of forms contained within a time-series based dataset in a quantitative and rigorous manner, reducing the subjectivity of observations made, thereby supporting the scientific observer. The features contained within the toolkit include the ability to handle non-uniform datasets, time-series component determination, frequency component determination, feature/event detection and characterization/parameterization of local behaviours. An application is presented of a case study dataset arising from the 'Lasgit' experiment.
Dengue fever (DF) and leptospirosis are serious public problems in tropical regions, especially in Manila, the Philippines. In attempting to understand the causes of DF and leptospirosis seasonality, meteorological factors have been suspected, but quantitative correlation between seasonality and meteorological factors has not been fully investigated. In this study, we investigated correlation of temporal patterns of reported numbers of laboratory-confirmed cases of both DF and leptospirosis with meteorological conditions (temperature, relative humidity, rainfall) in Manila. We used time-series analysis combined with spectral analysis and the least squares method. A 1-year cycle explained underlying variations of DF, leptospirosis and meteorological data. There was a peak of the 1-year cycle in temperature during May, followed by maxima in rainfall, relative humidity and number of laboratory-confirmed DF and leptospirosis cases. This result suggests that DF and leptospirosis epidemics are correlated not only with rainfall but also relative humidity and temperature in the Philippines. Quantifying the correlation of DF and leptospirosis infections with meteorological conditions may prove useful in predicting DF and leptospirosis epidemics, and health services should plan accordingly.
We investigated the seasonality of age-specific tuberculosis (TB) in Japan. To allow the development of TB control strategies for different age groups we used a time-series analysis, including a spectral analysis and least squares method, to analyse the monthly age-specific numbers of newly registered cases of all forms of active TB in Japan from January 1998 to December 2013. The time-series data are reported in 10-year age groups: 0–9, 10–19, …, 70–79, and ⩾80 years. We defined the contribution ratio of the 1-year cycle, Q1, as the contribution of the amplitude of a 1-year cycle to the whole amplitude of the time-series data. The Q1 values in the age groups corresponding to adolescence and middle life (10–39 years) and old age (⩾70 years) were high. The peaks in the active TB epidemics for the ⩾70 years age group occurred in August and September, 1–2 months behind the peaks for the 10–39 years age group (June and July). An active TB epidemic might be attributable to travel by public transport and irregular employment in the 10–39 years age group and immune system suppression by low winter temperatures in the ⩾70 years age group.
Annual periodicities of reported chickenpox cases have been observed in several countries. Of these, Japan has reported a two-peaked, bimodal annual cycle of reported chickenpox cases. This study investigated the possible underlying association of the bimodal cycle observed in the surveillance data of reported chickenpox cases with the meteorological factors of temperature, relative humidity and rainfall. A time-series analysis consisting of the maximum entropy method spectral analysis and the least squares method was applied to the chickenpox data and meteorological data of 47 prefectures in Japan. In all of the power spectral densities for the 47 prefectures, the spectral lines were observed at the frequency positions corresponding to the 1-year and 6-month cycles. The optimum least squares fitting (LSF) curves calculated with the 1-year and 6-month cycles explained the underlying variation of the chickenpox data. The LSF curves reproduced the bimodal and unimodal cycles that were clearly observed in northern and southern Japan, respectively. The data suggest that the second peaks in the bimodal cycles in the reported chickenpox cases in Japan occurred at a temperature of approximately 8·5 °C.