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Peace research – Just the study of war?

The concept of peace has been under discussion in peace research from its start over 50 years ago. This article reviews the debate on broader and narrower conceptions of peace and investigates empirical patterns in the first 49 volumes of Journal of Peace Research, with some comparisons with Journal of Conflict Resolution. Negative peace, in the sense of reducing war, was the main focus in peace research from the inception. But positive peace, in the sense of cooperation or integration, has also always been on the peace research agenda, as reflected in the contents of both journals. Over time, a larger share of the articles in JPR has ‘violence’ or related terms in the title, while the incidence of the word ‘peace’ is fairly stable. Furthermore, articles on peace generally have fewer citations than those with violence-related terms. A broad concept of peace, as encouraged by the definition of positive peace as the reversal of structural violence, was popular in peace research for a decade or so, but has largely evaporated. To some extent, peace research has returned to its original agenda, although the main attention has shifted from interstate war to civil war and to some extent to one-sided and non-state violence. Articles dealing with patterns of cooperation, the traditional meaning of positive peace, now tend to address the liberal agenda and ask how they can foster a reduced probability of violence. Despite the ‘gender gap’, the increasing share of female authors in the journal appears to have had little influence on these developments although it may well have had other effects.

The birth of peace research 1 Peace research was born at the intersection of peace activism and the emergence of modern social science. Although war and peace have always been key issues in the field of international relations (Kant, 1795(Kant, /1991Knutsen, 1997), it was only in the 1950s that calls arose for the systematic investigation of the conditions of peace as a special academic field or even a separate discipline. We are unable to identify the first person to use the term 'peace research', 2 but Johan Galtung -the founder of PRIO and of this journal -was certainly an early user in a pacifist manifesto published in Norwegian (Galtung, 1959). 3 At the time, backed by a double master's degree from the University of Oslo in statistics and sociology, Galtung was an instructor in sociology at Columbia University. At the same time he was active in the Norwegian section of War Resisters' International, which also published his book. One of the chapters called for the establishment of peace research institutes, in Norway and internationally. PRIO was founded in 1959 as the 'Section for Conflict and Peace Research' of the Institute for Social Research. This was a private foundation set up by social scientists with financial sponsorship from a scion of industry, at that time a rather unusual alliance in Norway. The Institute had for some time conducted a program on conflict research in collaboration with US scholars (Rinde & Rokkan, 1959). PRIO obtained public funding in 1964, 4 started JPR in the same year, and became fully independent in 1966. 5 At about the same time, academics concerned about the nuclear arms race and about the human condition more generally, founded Journal of Conflict Resolution (in 1957) 6 and the Center for Conflict Resolution at the University of Michigan in 1959, with sociologist Robert C. Angell and economist Kenneth Boulding as co-directors. The University of Michigan also became the home of the Correlates of War (COW) Project, founded by J. David Singer, in 1964. Although the Center folded in 1971, the COW project prospered, and JCR was taken over by Sage with Bruce Russett starting his 37-year editorship in 1973. The behavioral revolution in sociology and political science was a prominent feature of the new disciplinein economics, of course, this reorientation had occurred several decades earlier. In other institutes founded in the 1960s, such as the chair in 'polemology' established in 1962 at University of Groningen (and first occupied by a prominent scholar in international law, Bert Röling) and the Centre for the Analysis of Conflict in London in 1966, 7 the statistical and model-based work was not as prominent. But JPR and JCR were founded as journals with an empirical orientation, committed to 'hard-nosed-peace research' in the words of the editors of JCR (Russett & Kramer, 1973: 4), although both also published nonquantitative articles from the start.
Two international organizations were founded in the early 1960s. The International Peace Research Association (IPRA) started up in 1963, 8 at the initiative of academics and activists in the Women's International League for Peace and Freedom, a venerable peace organization; indeed two of its leaders had won individual Nobel Peace Prizes. 9 The founding meeting was sponsored by several Quaker organizations. Its Peace Research Newsletter, edited by Elise Boulding (wife of Kenneth Boulding and later to become an academic of considerable standing in her own right), served an important information function for international peace research in the early years, and also as a link to peace activists. The biannual IPRA conferences were also meeting-grounds between academics and activists. JPR was published 'under the auspices of IPRA ' from 1967 to 2002. A parallel institution, the Peace Research Society (International) 10 was founded in 1963, mainly as a result of the efforts of Walter Isard, a professor of regional science, then 1 A more detailed history of the peace research movement is found in Wiberg (1988) and a history of PRIO in Forr (2009). See also UNESCO (1967). 2 As early as 1917 a Norwegian peace organization petitioned the Norwegian Parliament for the establishment of a university chair in 'peace science' (Fetscher, 2013: 70). The proposal failed and the term didn't take hold. 3 In Web of Science the term 'peace research' appears in the title of an article for the first time in 1963 (Singer, 1963). The earliest reference in JSTOR is from 1941, to a Peace Research Group at the Graduate Faculty of Political and Social Science, New School for Social Research, New York (Feiler, 1941 (Isard, 2000: 31). at the University of Pennsylvania. 11 Isard was also the principal founder of the discipline of regional science. A tireless organizer, he ran a series of conferences on the topic in the USA and in Europe. He was a Quaker and had been a conscientious objector during World War II. Papers from his second peace research conference were published in JPR's first special issue at the end of its first volume, featuring an article on the economics of disarmament by one of Isard's old mentors, Wassily Leontief. The papers were simultaneously published as an issue of Isard's own journal, Papers, Peace Research Society (International). Beyond this, efforts at closer coordination between PRS(I) and IPRA failed. 12

A happy marriage?
Despite an auspicious start, relations between the activists and the academics were not always happy. The very name 'peace research' had not met with universal acceptance. When first proposing it around 1960, Galtung encountered objections from academics as well as research bureaucrats and politicians. 'What a horrible word', a senior civil servant in the Norwegian Ministry of Education is reported to have said at the time (Galtung, 1985: 141). Even sympathetic academics felt that 'conflict' was more established as an academic term and others were nervous that 'peace' had been given a bad name by Soviet-sponsored 'peace campaigns' that promoted Eastern Bloc policies in sheep's clothing. PRIO's first name was a compromise, which included conflict as well as peace. It was not until early 1964 that Galtung ventured to drop 'conflict' in PRIO's name and left it out of the name of JPR. However, shortly before that, the first proposal for the new journal was still titled Journal of Conflict and Peace Research. 13 Seven years earlier, the founders of JCR 'after much discussion' settled for 'conflict resolution' rather than 'peace' for the name of the journal. This was, among other reasons, because '''peace'' is a word too much abused these days' (anon, 1957: 2), 14 although an academic pioneer in the USA had championed the term 'science of peace' several years earlier (Lentz, 1955) and had established the Peace Research Laboratory as early as 1945. 15 In Sweden, the compromise term 'peace and conflict' was adopted when junior chairs in peace research were established at three universities in 1971 and that term remains till this day in the name of the department at Uppsala University, while Gothenburg University has settled for 'peace and development'. When Galtung got a chair at the University of Oslo in 1969, it was labeled 'conflict and peace research'. 16 An intergovernmental committee charged with the task of funding research at the Nordic level was established in 1971 and was named the 'Nordic Cooperation Committee for International Politics, including Peace and Conflict Research' -the name clearly reflecting who had won that particular interdisciplinary tug of war. As early as 1959, an independent institution in Lancaster called itself the 'Peace Research Centre' 17 and 1961 saw the birth of the Canadian Peace Research Institute. The term 'polemology' was used in France 18 as well as in the Netherlands, with occasional uses of 'irenology' (Starke, 1968). The US affiliate of IPRA has been known since 2001 as the Peace and Justice Studies Association.
Although activists and peace researchers were allies in the struggle for the term 'peace research', relations between them eventually soured. Just as the behavioral revolution was taking hold in sociology and political science, the student revolt occurred, first in Berkeley in 1964 and then in Europe from 1968 on. The liberationist, even anarchist, tone of the first insurgencies at the universities sounded a note that was superficially 14 However, JCR did not shy away from the use of term 'peace research'. Cf in particular a special issue, Fink & Boulding (1972). The journal also had a subtitle which included the words 'research related to war and peace'. 15 Cf. UNESCO (1967). 16 Galtung occupied the chair only until 1977. His successor, who was hired in 1980, soon had the designation changed to 'international conflict studies'. For a detailed history of the establishment of the chair and the many conflicts surrounding it, see Fetscher (2013). Her work is also a rich source of information and references on the history of peace research more generally. 17  favorable to peace, epitomized in the slogan 'Make Love Not War'. But the student revolutionaries were not enamored by things American, including 'American social science'. The behaviorist tone of much of peace research became a source of suspicion, and so did its 'neutral' stand in the East-West conflict. Many, including some young peace researchers, turned to Marxism (mostly the Maoist rather than the Soviet variety) and the liberation eventually turned into dogma and strong support for violence. Some peace researchers, Johan Galtung in particular, modified their views on methodology as well as substance. Galtung (1974) praised 'invariance-breaking' as a more important goal of social science than 'invariance-seeking' and Galtung (1969) launched the concept of 'structural violence' as an academic tool to shift the focus away from exclusive attention to the East-West conflict towards a higher priority for the North-South conflict. For most activists, this was too little, too late.
But for others it was too much. Walter Isard had long been skeptical of Galtung's concept of 'positive peace', which he perceived to be dominant in IPRA. Indeed, this was a key objection to closer collaboration between PRS(I) and IPRA (Isard, 2000: 32). Nevertheless, many scholars participated in both conferences. However, things came to a head when PRS(I) organized a US conference on the Vietnam War in 1968. At a meeting in Copenhagen in 1969, the Vietnam conference papers were criticized for one-sidedness that could reduce peace research to an unwitting tool of US foreign policy. Increasingly, Walter Isard felt that it was difficult for serious scholars to identify with 'broad-ranging peace researchers, some of whom are known to look at the world through rose-colored glasses' (Isard, 2000: 47). He persuaded the members of PRS(I) to change its name to Peace Science Society (International). 19 The organization's annual meeting continues to be an important meeting-ground for scholars concerned with war and peace, while IPRA has increasingly taken an activist orientation. In 1998, Scandinavian peace researchers took an initiative to forge a closer alliance between IPRA and JPR, where IPRA's Secretary-General Bjørn Møller joined the editorial committee and copies of the journal went to the whole membership. This proved to be an unholy alliance, leading eventually to the complete abolition of the IPRA-JPR partnership, although Møller remained on the editorial committee long after he had resigned from his IPRA position. Today, the peace science meetings remain an important source of articles for JPR, while few if any papers have first been presented at IPRA. In early years, the periodic Nordic peace research conferences were also important for JPR, but more recently the annual convention of the International Studies Association has emerged as the most important venue for mainstream peace researchers and as a source of articles both for JPR and JCR.
Early peace researchers were careful to draw a line between research and activism. The cover of the first issues of JPR stated that authors were free to develop policy conclusions, but the 'journal as such will never support any specific peace policy' and 'no valid article is excluded on the basis of the kind of policy it may favor'. In the current version, 'articles directed towards ways and means of peace are favoured', but '[w]ithout sacrificing the requirements for theoretical rigour and methodological sophistication'.

Just the study of war?
In the early days of peace research, Berenice Carroll (1972: 593, 595) worried that there seemed to be a cult of power in peace research and that the field was dominated by the study of major-power war and paid little attention to broader aspects like violence in society more generally and problems of injustice, exploitation, and oppression. In recent years, related critiques have been formulated by others. For instance, Brock-Utne & Garbo (2009: 3) warn that the increasing tendency in peace research to apply broader concepts of security may provide an inadvertent excuse for militarization. Johan Galtung (2009), now increasingly critical of his intellectual child, has suggested that PRIO ('an old age home from the 1950s') is becoming an arm of the Norwegian Foreign Ministry and should change its name to something like the Norwegian Institute for Security Research. Jørgen Johansen (2003), at that time coordinator of the peace studies program at the University of Tromsø, charged that peace research in the Nordic countries had degenerated into violence research. Counting the number of conflicts, as in the Uppsala Conflict Data Program, smacks of 'necrophilia'. Citing a statement from Wallensteen (1988: 8) -'peace research concentrates on the question of violence', and particularly on 'organized violence in societies ' -Johansen (2006) agreed that this had been the case in the past, but that peace research badly needed a reorientation. In the article that Johansen cited, Wallensteen himself had actually stated that although research on the causes of war stood at the core of peace research, there was also a second tradition of peace research that 'draws inspiration from hopes rather than traumas' and identified this with positive peace in the original sense of the term. Klein, Goertz & Diehl (2008: 67) argue that a negative definition of peace is inadequate: if we want to explain why some are wealthy, it is not useful to define them as being 'not poor'. Inspired by a celebrated study of foreign news published in JPR (Galtung & Ruge, 1965), the term 'peace journalism' has also gained considerable popularity, in distinction to 'violence/war/victory journalism'. In addition to being oriented to conflict and its resolution (as distinct from violence and war), solution-oriented (as opposed to victory-oriented), and people-oriented (rather than elite-oriented), peace journalism is also supposed to be 'truth-oriented' rather than 'propaganda-oriented'. 20 Although some of the complaints about present-day peace research are phrased in less than academic language, we take them sufficiently seriously to try to put them to an empirical test below. But first we need to look more closely at the concept of peace.

Broader concepts of peace
The Cold War and the threat of a nuclear Armageddon were certainly core concerns among early peace researchers. In a review of the first 12 volumes of Journal of Conflict Resolution, the then managing editor confirmed that international war, at least in the beginning, was the phenomenon of central interest for that journal (Converse, 1968: 475). Indeed, the first editorial in the journal had stated that the prevention of global war was by far the most practical problem facing the human race (anon, 1957: 2). J. David Singer (1963: 13) observed that US intellectuals had finally adopted the notion 'that we are drifting toward nuclear cataclysm and that the intellectual should -and perhaps can -do something about it'.
The first generation of the COW dataset (Singer & Small, 1972) was exclusively on interstate war. The COW data on civil war first appeared ten years later (Small & Singer, 1982), although the number of ongoing civil wars had long exceeded the number of interstate wars. A fairly lone voice in the peace research community at the time, Rummel (1984Rummel ( , 1994 argued that violence by governments against ordinary citizens ('democide') had claimed many more lives than war in the 20th century and Harff & Gurr (1988) found that for the post-World War II period, genocides and politicides had claimed at least as many lives as all international and civil wars together. In an influential book, Gurr (1995) also directed the attention of peace researchers to the plight of ethnic and other minorities. But it was not until the new millennium that quantitative peace researchers started engaging in systematic annual data collection on what came to be known as 'one-sided violence' (Eck & Hultman, 2007) and 'nonstate violence' (Sundberg, Eck & Kreutz, 2012).
While peace research enlarged its perspective on violent conflict, there was an underlying feeling that peace had to be something more than the absence of violence. To some extent, this was a reflection of the old dilemma of 'peace vs. justice'. The Norwegian Nobel Committee had long awarded prizes to human rights activists, and Galtung (1964) formulated concepts of 'negative peace' and 'positive peace' as the twin goals of peace research. Negative peace was the absence of war and violence. Positive peace was defined as 'the integration of human society' (Galtung, 1964: 2), but its precise nature was not entirely clear and would have been hard to operationalize. A joke going around peace research circles at the time was that 'peace' was a little bit like 'Paradise' in Christianity, a nice place -but it's not obvious what you do there except float around in white garments. 21 Galtung (1969) completely changed this. In response to the harsh critique from young radicals in the peace research movement, 22 Galtung now redefined positive peace as the negation of 'structural violence'. This was a different kind of violence from 'direct violence' (actor-oriented violence) since it emanated not from individual or group actors, but from the structure of a social system. If people starved, and the starvation was unnecessary because enough food was available, the social structure was to blame. The ambition was to be able to operationalize 'structural violence' and to test the notion of the young radicals that there was much more violence in the North-South conflict than in the East-West conflict. A framework for operationalizing the concept was developed by Galtung & Høivik (1971) and Høivik (1977), who used demographic data to estimate the annual loss of life from structural violence at 18 million, largely in line with an earlier estimate by Köhler & Alcock (1976). 23 These estimates seemed to confirm the claims made by the young Turks: the North-South conflict did indeed cause the loss of more human life than the East-West conflict, although obviously this would 20 See Galtung (1998Galtung ( /2013 and Lynch (2014: 41). 21 Personal recollection of the senior author of this article. 22 In particular Schmid (1968), although this was only acknowledged in an endnote (Galtung, 1969: 186). 23 Galtung (1971), in his most-cited article, explored imperialism as one of the major examples of structural violence. no longer be true if nuclear deterrence were to fail and general war between NATO and the Warsaw Pact broke out.
Not all peace researchers were convinced. Kenneth Boulding (1977: 78) thought that Galtung's term positive peace seemed to contain 'any state of affairs which gets high marks on his scale of goodness' and in fact 'may have very little to do with peace'. Boulding (1977: 80) also criticized Galtung for underestimating the costs of inequality, a critique formulated more sharply by Rummel (1981: 83, 50) who saw Galtung's view as 'a socialist theory of peace' and positive peace as 'a construct within a neo-Marxist theory of exploitation'. While JPR committed itself to devoting more attention to 'new forms of violence such as terrorism, police and para-military repression, and exploitation through new division of labor internationally and nationally ' (anon, 1978: 2), JCR under its new leadership had expanded its focus in a more modest way by promising to devote more attention to 'intranational conflict' (Russett & Kramer, 1973: 5). The efforts at quantifying structural violence fizzled out, and ever-wider interpretations of the concept came to dominate the literature. Any real or perceived injustice could be interpreted as 'structural violence'. Violence could even be psychological and not only physical (Galtung, 1969: 173) and could be applied to any level of social organization from the interpersonal to the global. Galtung (1990) added to the toolbox the concept of 'cultural violence', which can be understood as the cultural tools that legitimize different forms of violence, perhaps in an effort to accommodate the increasing influence of constructivist and postmodern ideas in peace research, but never caught on in mainstream peace research. While the term structural violence is now rarely used in the tradition following the early Galtung, the term still occurs regularly in other social sciences such as anthropology and criminology.
In the early 1980s a somewhat similar discussion arose about the proper definition of 'security'. The Palme Commission launched the concept of 'common security' (Palme et al., 1982) and later Arthur Westing (1989) and others started referring to 'comprehensive security', of which 'environmental security' would be an important component. The Copenhagen School of International Relations expanded the concept of security to include military, political, societal, economic, and environmental dimensions (Buzan, Waever & de Wilde, 1998). In 1994, the Human Development Report promoted the term 'human security' (UNDP, 1994), which encompassed economic security, food security, health security, environmental security, personal security, community security, and political security. This wide conception of security was meant to accommodate those who felt that a traditional state-based security concept, aimed at protecting national territory, was overly narrow. At the same time, critics argued that the wide human security concept, like structural violence, was excessively broad. Thus, the Human Security Report, while retaining the emphasis on the protection of individuals, settled for a narrower definition of human security, focusing on 'violent threats to individuals' (Mack, 2005: 1).
More recent attempts to measure peace include the Global Peace Index 24 and the Peace Scale (Klein, Goertz & Diehl, 2008). While the former has been very successful in getting international media attention, neither of these measures has so far had much impact on the academic study of war and peace, although Bayer (2010) has used the Peace Scale in a study of democracy and peaceful transitions.

War and armed conflict
In a review of the first 15 volumes of JPR, Wiberg (1981) points out that only a single article (Fabbro, 1978) focused solely on the empirical study of peaceful societies and even that article focused largely on the absence of violence at different levels from the interindividual to external wars. On the other hand, numerous articles have focused exclusively on armed conflict. An early example is Kende (1971), which analyses 97 'local wars'. The presentation of new datasets on armed conflict has become an important element in JPR, with Gleditsch et al. (2002) -the third most-cited JPR article ever 25 -as the most prominent example. The shift in attention after the end of the Cold War -from interstate war to civil war and to some extent one-sided violence -does not, of course, decrease the dominance of negative peace.
However, the early volumes of JPR contain a number of articles devoted to forms of peaceful interaction, such as summit meetings, development assistance, international integration, diplomacy, and even international aviation. Publishing such articles in JPR could only be 24 http://www.visionofhumanity.org/#/page/indexes/global-peaceindex. Although the original GPI focuses largely on measures of violence, the 2013 report includes an index of positive peace, which includes peace-promoting attitudes, structures, and institutions. 25 A search on the 'author' file of Web of Science seems to indicate that it is the second most-cited article, but a quirk in the indexing system seriously underestimates the number of citations to Galtung (1971), as the interested reader can verify by using the 'cited author' function.
justified as explorations of positive peace in the original sense of the word, though that term rarely if ever occurred in them. Roughly a quarter of the articles in the first four volumes of JPR can be classified as dealing with positive peace in this sense. There were also several articles on nonviolence. The increasing influence of dominance theory from the late 1960s, as evidenced in the emergence of the concept of structural violence and the interest in imperialism, implied a greater skepticism to many forms of peaceful interaction. If these were asymmetric, as in trade between unequal partners, they might generate conflict rather than peace. This trend was not broken until the 1990s when the democratic peace and later the liberal peace became recurrent themes in JPR. Even then, when the pioneer article on the liberal peace (Oneal et al., 1996) was published in JPR, it was accompanied in the same issue by an article questioning the liberal model in terms reminiscent of dependency theory (Barbieri, 1996).
The recent two decades have seen a return to the original agenda with the reduction of armed violence as the main focus, but with attention clearly shifting from interstate war to civil war and other forms of internal violence. Figure 1 shows the share in titles and abstracts in JPR and JCR with the words 'peace*', 'war*', 'conflict*', and 'violen*' (which includes 'violent' as well as 'violence') (see Appendix for description of the data). 26 The pattern is consistent with the notion that research has moved from interstate war to forms of internal violence. Especially for JPR, the share of articles with 'conflict' or 'violen*' in the title has increased. Additionally, in the last decade, 'war' is more often found in the context 'civil war' (14 articles out of 209 with 'war' in title/ abstract in the period 1993-2002 versus 77/232 between 2003 and 2012). The increasing use of 'peace' around the year 2000 can be attributed to research on the democratic peace.
To get an idea of the contexts of these words, we conducted a more open-ended search for the most common terms with two or more words in the form of a word  1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010 year Share of articles with [word] in title or abstract cloud for JPR. This can be seen in Figure 2. The most common combination of 'war' with other words is 'civil war', reflecting dominant trends in research on armed conflict after the Cold War. Indeed, 'civil war' is more common than 'Cold War'. A caveat here is that the word cloud does not take into account the increasing number of articles in JPR, which went from four to six issues a year in 1998 and switched to a larger format with more space in 2010. The prominence of the term 'human rights' may to some extent illustrate the persistence of articles relating to positive peace in the original sense. However, articles on human rights now increasingly focus on the causes of major human rights violations, in other words another negative peace theme. Articles on cooperation and other forms of peaceful interaction increasingly emphasize how these serve to reduce the probability of armed conflict, in line with thinking about the liberal peace. Thus, articles on positive peace in the original sense now contribute to research on how to overcome negative peace. Of course, the increasing focus on negative peace may also in part be a result of an enormous rise in submissions, which forces the editors of the journal to focus on its main mission. Figure 3 shows the number of published articles in JPR and JCR with the words 'structural violence', 'human rights', 'democratic peace', and 'peacebuilding/ keeping' in the title or abstract. Naturally, the term 'structural violence' does not occur before 1969. The initial enthusiasm for the new concept in JPR is reflected in the peak in the 1970s (although there is only a single year with two articles with this term in the title). From the early 1990s, the term virtually disappears from JPR, although two years in the last decade have one article each. The use of the term 'positive peace' in the abstract or title (allowing for up to 20 characters between the two words; figure not shown) peaks at about the same time as 'structural violence', but is zero for most volumes. In JCR, 'structural violence' has never occurred while 'positive peace' has only occurred once in the title or abstract of an article. In both journals, 'human rights', 'democratic peace', and 'peacebuilding/peacekeeping' are topics on the rise, although some of the steam may have run out of the democratic peace, perhaps because of the ascendance of articles on the liberal peace or, more recently, the capitalist peace.
Largely unrelated to the discussion about wider and narrower concepts of peace, early volumes of JPR and JCR had several articles using game theory or other formal models (e.g. Hansen & Ulrich, 1964;Schelling, 1957). Such tools could be applied to cooperation as well as conflict, including cooperation and coordination during conflict, and could serve as a bridge between negative and positive peace in the traditional sense. Over the years, however, JPR has not been a major outlet for formal modeling. In JCR, such articles have played a more important role, and the journal for many years had a separate 'gaming editor'.

A gender dimension?
Some of the critics of 'war research' have linked gender to this debate. Some prominent scholars of feminist international relations have argued that feminist IR must take a different path than the positivist orientation that has been dominant in the profession. In a widely cited article, Tickner (1997: 224) argues that a broad conception of security, which emphasizes economic and environmental dimensions, is more compatible with feminist scholarship than the traditional view that centers on the integrity of the state. Feminist international relations differs from traditional IR (whether realist, neoliberal, or peace research) in theory as well as methodology (Tickner, 1997: 613). Blanchard (2003Blanchard ( : 1292 contends that '[f]eminist incursions in the . . . security can be usefully situated on the ''widening'' side of the . . . debate' and both he and Tickner acknowledge the usefulness of the concept of structural violence. Galtung (1996: 30ff) identifies patriarchy as a form of structural violence and formulates the 'equation' man:woman ¼ war:peace. Confortini (2006: 340ff), however, finds that Galtung's understanding of patriarchy left much to be desired, and that he was 'unable to recognize the vast The figure shows the most common N-grams (two or more words appearing side by side) in titles  and titles/abstracts  in JPR. For an explanation of the data, see the Appendix.
implications gender has for violence and peace as social practices'. Nevertheless, she views an alliance between peace studies and feminism as possible and in the best interest of both (p. 356). We are unable to test the influence of all of these ideas on the development of peace research. Moreover, far from all women scholars in international relations and peace research have enrolled in the radical and anti-behaviorist feminist camp. 27 We would nevertheless expect an increasing representation of women among the authors in JPR to be associated with an increasing concern with positive peace and extended concepts of security.
Male scholars have always been overrepresented in peace research and in international relations and JPR is no exception. Figure 4 shows how female authorship (modestly defined as an article with at least one woman author) has increased over time. Although there is a considerable way to go before men and woman are represented equally in the columns of the journal -thus reducing 'gendered structural violence' in a terminology  1970198019902010197019801990201019701980199020101970198019902010 in title or abstract

Figure 3. Structural violence and other popular terms in JPR and JCR
The figure depicts the number of articles published in JPR and JCR each year with the term 'structural f20g violence', 'human rights', 'democratic peace' or 'peacef10gbuilding/peacef10gkeeping' in the title or abstract. f20g indicates that we allow up to 20 characters or blank spaces between the two words. For instance, the title of Galtung & Høivik (1971) is 'Structural and direct violence: A note on operationalization'. For a description of the data, see the Appendix.  The figure shows the fraction of articles in JPR with at least one female author. See Appendix for a description of the data. 27 In fact, many women have used quantitative methods in international relations and peace research (for an early example, see Zinnes, 1967) and many women scholars now investigate topics of key concern to women with the use of quantitative methods (e.g. Caprioli, 2000). once popular in peace research -female authorship has more than doubled since the start. The dip after the first few years requires a bit of explanation. Co-founders of PRIO along with Johan Galtung were two young women, Mari Holmboe Ruge and Ingrid Eide, the latter then his wife. Like other PRIO staff and associates at the time, these two women were pushed into publication at an early stage. Not unusually for a new journal, in-house publication was quite frequent at the outset. By the end of the 1960s the two women had left PRIO and Galtung himself was also on the way out. In four volumes of the next ten, there were no female articles at all! Given that we found only a very modest time trend for articles about peace, it would be surprising if the increase in female authorship (and stronger representation in editorial decisionmaking) had much impact on the use of the term. Of course, in theory women could have written more about peace while cancelled out by men writing less. In fact, the curve for peace in male only articles overlaps the curve for articles with female authorship almost exactly (figure not shown). We also tested whether gender was related to the probability of 'peace' or the three violence terms occurred in the title or the abstract, but did not find any significant differences. That does not mean that the stronger representation of women in JPR has not had an impact on the journal. The increased interest in the effects of violence (a common hypothesis being that civilians, including women and children, bear a greater burden of armed conflict) and the recent reawakened interest in nonviolence (Chenoweth & Cunningham, 2013) may well be ascribed in part to a gender factor, but we have no way to test this systematically.

What topics are most cited and when?
From the start, JPR has been well cited and in recent years the journal has been in the top ten in terms of the two-year or five-year impact factor. 28 Initially, its reputation was very much due to the articles by Johan Galtung, just as these articles were (and remain) important to his reputation as a scholar. In the first two volumes, he contributed an article to every issue and volume 7 (1970) was the first volume without a Galtung article. His most recent JPR article appeared in 1990. Since most of his articles were frequently cited, JPR's overall citations depended a lot on Galtung's. However, his share of the total citations to JPR declined from 40% in 1972 to 13% in 1992 (Gleditsch, 1993;Gleditsch, Larsen & Hegre, 1994). 29 More than any individual subjective impression, citations to JPR articles reflect the interests of a broader research community in different types of articles. Thus, if the peace research profession generally, and not just JPR, has given priority to articles about negative peace, we would expect such articles to be more frequently cited. An overall well-cited theme is in turn likely to result in more submissions and more published articles. Also, editors want to position their journals in certain debates, and a number of highly cited articles can influence the editor's choice of what articles to publish. Articles vary greatly in their impact: the median citation count for all JPR articles over the entire period is 4, the range is from 0 to 565, and the interquartile range is from 1 to 10.
We have analyzed citation counts for each JPR article, using the keywords introduced earlier as defining the four themes 'violence', 'conflict', 'war', and 'peace'. Figure 5 shows how, over time, using these words in the article's title is associated with higher or lower citation counts than the average similar article without the corresponding term.
The metric on the y-axis is the difference in the expected number of citations, controlling for a number of factors known to influence the citation count, such as time since publication, page length, number of coauthors, and -most importantly -the average number of citations in each volume. Hence, the value 0 indicates that a corresponding theme is cited on par with the average article in that specific volume, not the global The metric on the y-axis is the expected difference in the predicted number of citations.
average. 30 Holding all these factors constant, we find that the term 'conflict' adds on average ten citations to a typical article published around the year 2000, whereas the term 'peace' subtracts about five citations. The four lines converge towards 0 on the right hand side, since very recent articles have very few citations, and hence seldom depart from the time specific average. Overall, articles with 'peace' in the title tend to receive fewer than average citations. There is rising interest in 'peace' articles from the late 1960s until the early 1990s, but then it drops again. The curve for 'peace' increases again in the most recent decade but it is a bit early to say whether this is more than a fleeting interest. At least in the early volumes, this may indicate that JPR was more interested in positive peace than the research community at large, which was more likely to cite other themes.
The term 'war' was cited less often than average for the first ten years, and is also associated with a major drop in expected citations for the period 1984-2000. However, for the last decade, this term has been associated with a major citation boost, probably because of increasing interest in civil war. A typical article with the term 'war' around 2004 had six more citations than the average article without this term. A cursory review of the most cited titles in titles in JPR indicates that the terms 'conflict' and 'war' overlap somewhat in the period after 1995, where the two corresponding graphs follow the same trajectory.
Largely hovering around the parity line, the term 'violence' was highly popular among JPR readers between 1985 and 1995. Articles with this term in the title could expect, on average, up to seven citations more than their counterpart.
Finally, the term 'conflict' is by far the most frequently cited of the four. Rarely beneath the parity line, 31 articles with the term 'conflict' in the title are more popular among JPR's readers, and in particular from 1995 and onwards. One might suspect that this effect is driven by a few very highly cited articles published in 2002 and 2004, but this does not seem to be the case. The fact that such articles have become more frequent (see Figure 1) and are also more often cited should indicate that both JPR and peace research in general have become more interested in this theme.

Conclusions
The concept of peace has been under constant discussion in peace research from the very start over 50 years ago. Many scholars advocate a broad concept of peace while others hold that peace research should focus on the traditional agenda of mapping and explaining physical violence between groups and investigating how it can be reduced. Critics have argued that peace research has become overly focused on war and violence and needs a reorientation. We do not take a stand on the normative issue, but have studied empirically the balance between articles focusing on peace and articles focusing on war, conflict, and violence in the first 49 volumes of Journal of Peace Research and its main competitor, Journal of Conflict Resolution. Negative peace, in the sense of reducing war, has always been the main focus in peace research. But positive peace, in the sense of cooperation or integration, has also always been on the peace research agenda, as reflected in the contents of the journal. Over time, a larger share of the articles has violence or related terms in the title, while the incidence of the word peace is more stable. There was no 'golden age' of peace research, which focused more clearly on peace. A broad concept of peace, as encouraged by the definition of positive peace as the reversal of structural violence, was popular in JPR (but not in JCR) for a decade or so, but has largely evaporated. Articles focusing on negative peace have also been more frequently cited, even though this effect varies over time. To some extent, peace research has returned to its original agenda, although there has been a clear shift away from interstate war to civil war and other forms of intrastate violence such as one-sided violence and non-state violence. Patterns of cooperation, the traditional meaning of positive peace, are still being investigated. But increasingly such articles focus on how nonviolent interactions foster a reduced probability of violence, in line with the liberal peace theory. Despite the gender gap in attitudes to war and peace found in many studies, the increasing share of women authors in the journal appears to have had little influence on the priorities in article themes, although it may well have had other effects. 30 We use the time-specific average citation score as the baseline since we can then report the differences in absolute citations. We find this to be a more intuitive statistic than the incidence rate ratios usually reported with count models. The figure is based on four regression models, where each term successively is interacted by a volume dummy. The predicted citation numbers are then predicted for each of the four terms. Figure 5 is based on a lowess regression with a conservative bandwidth on the predicted citation numbers, as there is quite a lot of noise in the raw dataset. The results in general are quite robust to the exclusion of highly cited articles or special issues, and even more so when the lowess smoothing is applied. See the replication dataset for a complete documentation. 31 The parity line, with the value 0 on the y-axis, indicates that an article is no more or less likely to be cited dependent on the inclusion of a given term.

Replication data
Our replication data and other supplementary material can be downloaded from www.prio.no/jpr/datasets.