Postmortem memory of public figures in news and social media
Who is remembered by society after they die? Although scholars as well as the broader public have speculated about this question since ancient times, we still lack a detailed understanding of the processes at work when a public figure dies and their media image solidifies and is committed to the collective memory. To close this gap, we leverage a comprehensive 5-y dataset of online news and social media posts with millions of documents per day. By tracking mentions of thousands of public figures during the year following their death, we reveal and model the prototypical patterns and biographic correlates of postmortem media attention, as well as systematic differences in how the news vs. social media remember deceased public figures.
Deceased public figures are often said to live on in collective memory. We quantify this phenomenon by tracking mentions of 2,362 public figures in English-language online news and social media (Twitter) 1 y before and after death. We measure the sharp spike and rapid decay of attention following death and model collective memory as a composition of communicative and cultural memory. Clustering reveals four patterns of postmortem memory, and regression analysis shows that boosts in media attention are largest for premortem popular anglophones who died a young, unnatural death; that long-term boosts are smallest for leaders and largest for artists; and that, while both the news and Twitter are triggered by young and unnatural deaths, the news additionally curates collective memory when old persons or leaders die. Overall, we illuminate the age-old question of who is remembered by society, and the distinct roles of news and social media in collective memory formation.
Being remembered after death has been an important concern for humans throughout history (1), and conversely, many cultures have considered damnatio memoriae—being purposefully erased from the public’s memory—one of the most severe punishments conceivable (2). To reason about the processes by which groups and societies remember and forget, the French philosopher and sociologist Maurice Halbwachs introduced the concept of collective memory in 1925 (3), which has since been a subject of study in numerous disciplines, including anthropology, ethnography, philosophy, history, psychology, and sociology, and which gave rise to the new discipline of memory studies (4). Over the decades, collective memory has moved from being a purely theoretical construct to becoming a practical phenomenon that can be studied empirically (5), e.g., in order to quantify to what extent US presidents are remembered across generations (6) or how World War II is remembered across countries (7).
Whereas oral tradition formed the basis for collective memory in early human history, today the media play a key role in determining what and who is remembered, and how (8⇓⇓–11). Researchers have studied the role of numerous media in constructing the postmortem memory of deceased public figures. A large body of work has investigated the journalistic format of the obituary (12⇓⇓⇓–16), which captures how persons are remembered around the time of their death (14). Taking a more long-term perspective, other work has considered how deceased public figures are remembered in the media over the course of years and decades (17⇓⇓⇓–21). As ever more aspects of life are shifting to the online sphere, the Web is also gaining importance as a global memory place (22), which has led researchers to study, e.g., how social media users (23⇓⇓⇓–27) and Wikipedia editors (28) react to the death of public figures. In the context of social media, the detailed analysis of highly visible individual cases, such as Princess Diana (24), pop star Michael Jackson (25, 26), or race car driver Dale Earnhardt (27), has revealed how people experience and overcome the collective trauma that can ensue following the death of celebrities.
Although such studies of individuals have led to deep insights at a fine level of temporal granularity, they lack breadth by excluding all but some of the very most prominent public figures. What is largely absent from the literature is a general understanding of patterns of postmortem memory in the media that goes beyond single public figures.
To bridge this gap, we draw inspiration from a body of related work that has studied the temporal evolution of collective memory using large-scale datasets—although, unlike our work, not with a focus on the immediate postmortem period of public figures. For instance, van de Rijt et al. (20) tracked thousands of person names in news articles, finding that famous people tend to be covered by the news persistently over decades. In a similar analysis, Cook et al. (19) further showed that the duration of fame had not decreased over the course of the last century. Beyond news corpora, the online encyclopedia Wikipedia has become a prime resource for the data-driven study of collective memory. Researchers have leveraged the textual content of Wikipedia articles (29), as well as logs of both editing (30) and viewing (31, 32), as proxies for the collective memory of traumatic events such as terrorist attacks or airplane crashes. Jatowt et al. (33) characterized the coverage and popularity of historical figures in Wikipedia, observing vastly increased page-view counts for people from the 15th and 16th centuries, a fact that Jara-Figueroa et al. (34) later attributed to the invention of the printing press. In addition to news and encyclopedic articles, books (35⇓–37) and social media (38, 39) have also emerged as important assets for studying collective memory.
Whereas the above works are primarily descriptive in nature, researchers have also developed mathematical models of the growth and decay of collective memory. Notably, as part of a rich literature on the evolution of performance, fame, and success in the arts and sciences (40⇓⇓⇓⇓–45), Candia et al. (46) analyzed thousands of papers, patents, songs, movies, and athletes, showing that the decay of the intensity of collective memory can be well described by a biexponential function that captures two aspects of collective memory: communicative memory, which is “sustained by the oral transmission of information,” and cultural memory, which is “sustained by the physical recording of information” (46).
We extend this literature by studying how the coverage of thousands of public figures in news and social media evolved during the year following their death. Our approach combines the Freebase knowledge base (47)—a comprehensive repository containing records for over 3 million public figures—with an extensive corpus of online news and social media compiled via the online media aggregation service Spinn3r (48), which comprises, for each day, hundreds of thousands of news articles from a complete set of all 6,608 English-language Web domains indexed by Google News and tens of millions of social media posts from Twitter, amounting to about one-third of full English Twitter (details in Materials and Methods; number of documents per day in SI Appendix, Fig. 1). The population of study consists of 2,362 public figures who died between 2009 and 2014 and received at least a minimum amount of premortem coverage both in the news and on Twitter. For each person, we tracked the daily frequency with which they were mentioned in the two media during the year before and the year after death, and operationalize postmortem memory via the resulting time series of mention frequency. (For details about data and preprocessing, see Materials and Methods.) Analyzing the mention time series allowed us to quantify the extreme spike and rapid decay of attention that tend to follow the death of public figures, a pattern well captured by a power law shifted by a constant additive offset. A cluster analysis of mention time series revealed four prototypical patterns of postmortem memory (“blip,” “silence,” “rise,” and “decline”), and a regression analysis shed light on the biographic correlates of postmortem memory and on systematic differences between postmortem memory in mainstream news vs. social media. We conclude that the prototypical persona with the largest postmortem boost in English-language media attention can be described as an anglophone who was already well known before death and died a young, unnatural death. Long-term attention boosts are on average smallest for leaders and largest for artists. Finally, while both the mainstream news and Twitter are triggered by young and unnatural deaths, the mainstream news—but not Twitter—appears to also assume an additional role as stewards of collective memory when an old person or an accomplished leader dies. Overall, the present work helps illuminate an age-old question: Who is remembered by society?
We strive to characterize the patterns by which postmortem memory evolves during the year immediately following the death of public figures. When considering this time frame, prior work has primarily taken a qualitative stance, asking how, linguistically, the mainstream and social media speak about small sets of deceased people (15, 16, 23⇓⇓⇓–27). In contrast, enabled by a comprehensive corpus of news and social media posts, we take a quantitative stance, asking about whom the media speak how much after death.
At the core of our analysis are time series of mention frequency. A person i’s “raw mention time series” specifies, for each day t relative to i’s day of death (t=0), the base-10 logarithm of the fraction Si