Renewable vs. Non-Renewable Resources as Causes of Conflict in Sub-Saharan Africa, a Time-series Analysis: 1970-2000 Samuel S. Stanton, Jr. Grove City College [email protected] Joseph J. St. Marie University of Southern Mississippi [email protected] Prepared for presentation at the American Political Science Association Annual Meeting 2008, Boston, MA. PLEASE DO NOT CITE WITHOUT PERMISSION OF THE AUTHORS Renewable vs. Non-Renewable Resources as Causes of Conflict in Sub-Saharan Africa, a Time-series Analysis: 1970-2000 Truly the “Heart of Darkness” appears to remain a “fire zone. Where poets speak their heart then bleed for it.”1 Over the past thirty-five years, nonAfrican developing countries experienced a decrease, while African countries experienced an increase in the outbreak of civil war (Collier and Hoeffler, 2002). While Africa and Asia are the primary locations of civil war today and were the primary locations of civil war during the Cold War, this work focuses on SubSaharan Africa. We choose Africa because of the growing publicity African conflicts receive and because of the general focus on Africa and Asia that emerges in the literature on civil war. Civil War The current primary arguments about civil war consider the importance of greed vs. grievance in explaining human behavior (Collier 1999, 2002, 2007, Fearon and Laitin 2003, Oechslin 2006). Greed vs. grievance has been further amended to consider feasibility (economic viability) and motivation (sociopolitical inequality), with the caveat that greed promotes feasibility of civil war and grievance is more motivational. This paper examines both economic feasibility and socio-political inequality perspectives as greed vs. grievance in the examination of civil war in Sub-Saharan Africa. Creating a nexus between the literature on resource wars and renewable natural resource scarcities, this research analyzes the affects certain resources (both renewable and nonrenewable) have on the occurrence, duration, and magnitude of civil wars in subSaharan Africa. This paper examines oil, diamonds and forested land2 as non-renewable resources that feed the greed and feasibility hypotheses. The paper examines freshwater and arable land, as renewable natural resource causes of civil war. Renewable natural resources are sources of inequality that lead to grievance and motivation for conflict. The importance of continued study of civil war falls into three areas. First, while conflict appears to be subsiding in the world, civil wars do continue and according to Bennett and Stam (1996) civil wars last about last about seven (7) 1 Borrowed from Robert Conrad and from the lyrics of “One Tree Hill” by U2. We are well aware that trees are a renewable natural resource. However, the demand for forestry products, particularly derived from old growth hardwoods, leads us to accept arguments that forestry products are part of the resources governments and rebels covet control over for monetary reasons. 2 1 years, while international conflicts last only about eleven (11) months on average. Secondly, civil wars are fought between parties that share and if both survive, will continue to share the same territorial limitations (as created by international borders) after the conflict concludes. Finally, civil war can be viewed as a conflict where defeat can mean the end of the existence of one or more parties to the war, making compromise in the settlement of the conflict difficult at best (Licklider, 1995). The primary question we seek to answer in this paper is: whether greed or grievance natural resources provide a better causal explanation for civil war in SubSaharan Africa. We examine the years 1970 to 2000 utilizing data from the Correlates of War, Civil War (Singer and Small 1994, updated by Collier, et al. 2007) using cross-sectional time-series models to test the impact of the greed vs. grievance hypotheses on the occurrence, duration and magnitude of civil wars in sub-Saharan Africa. Preliminary indications find a stronger case is made for grievance and motivation hypotheses in the explanation of civil wars in SubSaharan Africa. To answer this intriguing question we divide the paper into six sections. The first and second examine civil war and its causes. The Greed versus Grievance hypotheses are introduced and explained. The third section outlines the hypotheses we use in testing our models. The fourth section introduces the data and explains the variables used in the analysis. The fifth section presents the results of the statistical analysis. Finally, we will offer some conclusions about the greed vs. grievance arguments, the veracity and quality of our own effort, and the direction for future research on civil war in Sub-Saharan Africa. The Causes of Civil War We must first establish the definitions of “greed” and “grievance” before looking at what exact factors are considered in testing these general ideas as causes of civil war. Greed quite simply is the desire to accumulate more of something to yourself or to the group you represent. In most cases of greed the desired object has monetary value. Accumulating a large amount of something of monetary value is perceived and in many cases translated into political power. Simply put, wealth begets wealth. Grievance refers to a person or group of people who are socially or politically differentiated from others, perhaps another ethnic or religious group. The reality or the perception on the part of the aggrieved group is that this differentiation, be it artificial or real, is negative toward them. This is akin to an in-group/out-group situation where benefits flow to the in-group but not he out-group creating hostility. An example of 2 extreme grievance would be a constitutional provision that prohibited members of a certain group within the population from all forms of political participation in the state. This group would definitely be aggrieved. The Greed Hypothesis At the center of the greed v. grievance debate is the work of Paul Collier, who along with Anke Hoeffler and others have authored several works in the last decade arguing that greed is the primary cause of civil war based on study of income growth, plunder of natural resources, financial ability to maintain military activity.3 Greed by all apprearance allows rebel movements to maintain viability (Collier 1999, 2007; Collier and Hoeffler 1999; Humphreys 2002). The primary argument of the greed hypothesis is that groups challenge the state for control of resources of monetary value. The resources primarily fall into what would be considered non-renewable natural resources. Nonrenewable natural resources are those resources that take over one human generation to replenish themselves. Most non-renewable natural resources require hundreds of years to regenerate and require great human effort to retrieve. Among the resources that are considered to be non-renewable would be oil, natural gas, diamonds, gold and silver, gemstones, and minerals. One renewable natural resource is usually accepted as a greed resource—forests. Forests provide a readily accessible source of both income and cover. While our paper is about renewable vs. non-renewable resources, we will allow forested land to act as a greed resource rather than a grievance resource. Most of the recent research has tested the greed hypothesis. Greed has been tested primarily in terms of commodity exports and done in either 5 year periods or country years (Collier and Hoeffler 2002, DeRouen and Sobek 2004, Fearon 2005). It has also been tested using income and economic growth (Collier and Hoeffler 2002, Fearon 2005). If studied in 5 year periods, exports and economic growth show a statistically significant relationship with civil war onset (Collier and Hoeffler 2002, Fearon 2005), but not when studied in country year format (Fearon 2005). In DeRouen and Sobek (2004) exports showed statistical significance in relation to multiple forms of civil war termination. Fearon (2004) includes contraband (illegal drugs, illegal trade in precious gems and minerals) in his study and finds that contraband was statistically significant in relation to civil war duration. Hegre etal (2001) include a variable called “development” in 3 Normally this citation would be given in text, but length leads to this footnote. Collier (1999, 2000, 2001, 2007); Collier and Hoeffler (2002, 2004), Collier, Hoeffler and Söderbom (2006); Collier, Hoeffler and Rohner (2007); Collier and Sambanis (2002). 3 their model, which measures per capita energy consumption (2001, 37) yet did not find it to be related to outbreak of civil war. This is important to note for greed arguments, as control of energy production resources is pootentially a great source of wealth. Lujala et al (2005) finds the presence and production of both primary and secondary diamonds are statistically significant in relation to civil war onset between 1945 and 1999. DeRouen and Sobek (2004) included a variable measuring forested land and found this to statistically significant in relation to multiple forms of civil war termination. The Grievance Hypothesis Grievance has also been tested repeatedly. Grievance is tested primarily in terms of political form, linguistic differences, and religious differences (DeRouen and Sobek 2004, Fearon 2004, 2005, Hegre etal 2001). The U-shaped curve has been repeatedly demonstrated in these studies, showing conflict more likely in transitionary states found in the lower scores of autocracy and democracy than in either highly authoritarian or highly democratic states. Interestingly ethnic fractionalization measured by ethnic linguistic fractionalization (ELF) has not show itself to be highly related to onset or duration of civil war, except when measured in five year periods (Fearon 2005). Our work looks primarily are resources as the elements of greed and grievance. Ross (2004) offers four (4) conclusions about resources and civil war. 1) oil dependence is linked to civil war onset, but not duration; 2) gemstones, opium, coca, and cannabis are not linked to onset, but lengthen existing wars, and timber’s role is untested; 3) no statistical evidence links agricultural commodities to initiation or duration of civil war; 4) claims that primary commodities are associated with the onset of civil war are not very robust (Ross 2004, 352). Ross is correct in stating that statistical evidence does not exist about agricultural commodities as a cause of civil war. This does not mean that agriculture per se has not been considered as an element of conflict. In studying the effects of resource degradation on conflict behavior, Porter (1995) Baechler (1998), HomerDixon (1994, 1999), and Klare (2001) each point out the negative affects of resource degradation on the welfare of a society. Baechler and Homer-Dixon particularly note the causal relation of resource degradation to conflict behavior. 4 These scholars have also focused on renewable natural resources as sources of conflict. Homer-Dixon (1999) refers to the social consequences of renewable natural resource scarcity and how this may lead to conflict. Of the renewable natural resources considered by scholars studying the relationship with conflict behavior, freshwater, arable land, and forested land are those most often considered to have a strong relationship with conflict behavior (Baechler 1998, Deudney 1990, Hauge and Ellingsen 1993, Porter 1995) Renewable natural resources in relation to conflict behavior are most appropriately viewed as grievance mechanisms. The scarcity of a natural resource can affect all people in society equally, but scarcity can also be structural, that is caused by the policy of a state. When scarcity is structural it has the potential to be used against opponents of the state. An example of this is a policy that makes ownership of water rights illegal for a certain group in a society. This group is now deprived of one of the necessary elements of life. This sort of deprivation is a grievance, desire to have access to a required element of human life is not greed, it is a desire to survive. Based on the literature we find there is a categorical difference between the resources that are greed based (sources of monetary wealth and income gain) versus grievance resources (those resources necessary to support life). This resource dichotomy provides an interesting means of studying civil war by testing both the grievance hypotheses regarding renewable natural resources and civil conflict and the greed hypotheses of civil war in determining which is a better explanation for civil war in Sub-Saharan Africa, where both greed resources and grievance resources are present (often both in abundance in the same country). We believe that renewable natural resources are a stronger causal explanation for civil violence based on the literature of environmental security and the wide divergence of findings regarding greed resources and civil war. However, in this work we test greed and grievance equally since there is no existing research that shows either greed or grievance to be beyond a shadow of a doubt the stronger cause of civil war. Hypotheses The dependent variable in this paper is civil war in sub-Saharan Africa. This study identifies a conflict as a civil war if it includes organized military action, at least 1,000 battle deaths in a given year, at least five percent of the deaths which were inflicted by the weaker party, and the national government at the time was actively involved, as defined by Singer and Small (1994). These 5 figures will be used from the original Correlates of War (COW) dataset developed by Singer and Small, as well as the updated Armed Conflict Dataset by Nils Petter Gleditsch (2002). Our study also considers two important aspects of civil war— duration, the temporal length of the conflict, and magnitude, the number of deaths caused by the conflict. With this in mind we offer the following hypotheses: Greed based hypotheses: H1: Presence of greed resource production will cause an increase in the likelihood of civil war onset H2: Presence of greed resource production will cause an increase in the duration of civil war H3: Presence of greed resource production will cause an increase in the magnitude of civil war Grievance based Hypotheses: H4: Renewable natural resource scarcity will cause an increase in the likelihood of civil war onset H5: Renewable natural resource scarcity will cause an increase in the duration of civil war H6: Renewable natural resource scarcity will cause an increase in the magnitude of civil war We do not discount greed as a potential cause of civil war, even though our sympathies based on extant literature appear to support grievance. Instead we propose through our hypotheses to test each with equal rigor. We now turn to a discussion of the data that will allow us to operationalize concepts found in the literature and hypotheses and finally to the models used in testing this data. Data and Variables Our data is grouped in a country-year format. We examine 46 countries in continental Sub-Saharan Africa from 1970-2000. The yearly panels are not equal, as not all countries in Sub-Saharan Africa were independent in every year covered in this study. The data also does not include the smaller, island-states of Sub-Saharan Africa, nor does it include Lesotho or Swaziland. The choice to not 6 include these states is based on the large amount of missing data for these countries. The dataset as complied has 1207 cases. The dependent variable will test is civil war. We want to test the viability of greed, measured as natural resources, in relations to three aspects of civil war—onset, duration, and magnitude. This requires 3 models utilizing 2 different techniques (OLS and Logit regression) for measuring the statistical relationship. The first and fourth hypotheses (likelihood of civil war) use a dichotomous variable, with “0” indicating a lack of civil war and “1” indicating the occurrence of a civil war. This data was gathered from Nils Petter Gleditsch’s updated version of the Correlates of War data (2004), originally compiled by Singer and Small (1994).4 The Correlates of War data is the premier study and analysis of civil wars. The data shows 202 cases where civil war occurred. In the vast majority of cases (1511) no civil war occurred. This is of little surprise, as violent conflict of any type is a rare occurrence. The second and fifth hypotheses use duration of civil war as the dependent variable, ranging from “0-12” with “0” indicating a lack of civil war occurring in that year and increasing to “12” indicating that a civil war composed all twelve months of that year, using the original COW data for the years 1960 – 1997 and the Uppsala Conflict Data Program and International Peace Research Institute, Oslo UCDP/PRIO Armed Conflict Dataset for the years 1998 – 2000 (2002).5 The mean value of duration is .91, indicating that in all 1713 cases an average civil war lasted less than one month. If we exclude the cases where no civil war occurred in the country-year observed, however, the mean value of duration is 9.48. This indicates that when a civil war did occur in a given country in a given year, the average duration of an actual event was approximately nine and one-half months. Onset and Duration have been tested repeatedly in the study of civil war. Magnitude, however, has received less coverage. In part this is due to the difficulty in measuring magnitude. Is the magnitude of civil war to be construed simply as the number of battle deaths in a calendar year or is it the total of all deaths? We must recognize that the magnitude of conflict could be measured in both military deaths and total deaths. Azam (2002) points out in a limited look at civilian vs. military deaths in African civil wars, that the differences are often staggering. For instance in the Angolan Civil War there were 21,000 military deaths over 16 years (1975-1991) and 320,000 civilian deaths in the Sudan 4 5 Civil war occurrence data is available at: http://new.prio.no/CSCW-Datasets/ Duration of civil war data available at: http://correlatesofwar.org/datasets.htm 7 between 1983 and 1990 there were 10,000 military deaths and 500,000 civilian deaths (Azam 2002, 132). Civil war magnitude despite being discussed has not often been tested. Thus, we propose a test. We test magnatude with the best and most complete data available which is battle deaths per year. Our two remaining hypotheses use a scalar dependent variable, measuring the magnitude of each civil war using the number of battle deaths per year, from 1960 – 1997. This data was gathered from Bethany Lacina’s Battle Deaths Dataset 1946 – 2005 provided by the Centre for the Study of Civil War and the International Peace Research Institute, Oslo (2006).6 While not a perfect measure, the numbers are still sobering to consider. The mean value of magnitude for all the cases in our data, measured as battle deaths per year, was 553.60 or roughly 554 battle deaths per year. If we limit this to actual observed cases of civil war occurrence, the mean value for magnitude is 5357.79. This indicates that when a civil war did occur in a given country in a given year, the average number of battle deaths was nearly 5358 per year. Independent Variables Our independent variables fall into two categories, those we believe are associated with greed and those that are associated with grievance. We address greed first, and then grievance. Certainly the list for each in not exhaustive, but given data limitations these variables are the best candidates to conduct our tests. Moreover, many have been used extensively before in published work establishing their theoretical significance. Greed Variables Oil Producing State This variable measures whether a state was an oil producing state in the year of observation. 397 of the 1207 cases in our data were oil producing states in the given year of observation. One-Third of Export GDP from Fuels Because oil as a resource is a greed resource, it is necessary to test whether greed comes from larger share of GDP from the production of oil. This measure is taken from Fearon and Laitin (2003). 119 of 1207 cases were countries in which fuels accounted for one-third or more of export GDP in the given year. 6 Magnitude of civil war data available at: http://new.prio.no/CSCW-Datasets/ 8 Diamond Producing State Diamonds have been argued to be one of the primary sources of funding for civil war and much of the atrocities in Africa. The presence of blood diamonds requires that a state be a diamond producing state. Borrowing from the World Development Indicators we use a dichotomous variable that measures whether a country was diamond producing. This is not the best measure possible, which would be volume or dollar amount per year of diamond production. However, secrecy within that industry makes such numbers difficult to find and unreliable when found. 440 of 1207 cases were diamond producing countries in a given year in our dataset. SXP (Interpolated) Lacking a quality measure for the years 1970-2000 for actual oil and diamond production we use interpolated sxp (Fearon 2005) a measure of the percentage of GDP represented by primary commodity exports. Primary commodities include minerals, ores, metals, and unrefined oil. The interpolation is necessary because this indicator is only available through the World Bank in five year measurement points. The mean value of SXP was .1761, indicating that for the average country in a given year of the data the portion of export GDP from primary commodities was almost 18%. The highest level of SXP was 56%. The standard error of the mean is .0039. Percentage of Lost Forested Land This measure gives the actual amount of forested land lost in a country in a given year from the amount of forested land present in the previous year. We use this measure to test for economic gain from timbering, which if reports in many news sources are to be believed, is a major source of deforestation. This percentage is based on forested land estimates found in CIA, Keesing’s World Record, United Nations, and World Development Indicator data. The mean percentage of lost forested land was .2216% with a standard error of .0298. For most countries the sources used indicate the loss of no forested land (1096 of 1207 cases have loss of 0%). At the extreme end of the spectrum one country reported in one year the loss of 20% of forested land. For each of the above variables we also have created one and two year lagged variables. It is entirely likely that desire to control wealth generated by these resources is built over time as those outside and inside government see the wealth generated by this resource in previous years and determine to take control of the resource by force in the current year. 9 Grievance Variables Percentage of Arable Land Lost This measures the percentage of arable land lost from the previous calendar year. The measurement is based on the same data sources as forested land. The belief is that land is a grievance resource given that all people must eat. Conversely it is not greed that makes people desirous of arable land when most people are involved in subsistence agriculture—as is the case in Sub-Saharan Africa—it is merely survival. The average loss of arable land was .2264% with a standard error of .0338. 1103 cases show no loss of arable land, the extreme case showed loss of 24% of arable land. Where loss occurred the norms were 1% (47 cases) and 2% (26 cases). Freshwater Scarcity Accurate data for the cubic feet of freshwater available in a country is not readily available for most of the world, and particularly not for much of Sub-Saharan Africa. Simply put, people require water to live. Not having access to fresh, potable water is a grievance. We turn to the question of freshwater scarcity and pollution as an environmental concern. In the CIA country data, Keesing’s country data, and the United Nations country data, there are a sections that mention environmental concerns. If that section mentions freshwater scarcity and/or pollution as an environmental concern in at least two of the three sources, we coded that as a 1 (freshwater scarcity/pollution present), if this was not listed as a concern in at least two of the sources, we coded it as 0 (freshwater scarcity/pollution not present). 711 cases showed freshwater scarcity/pollution was an issue of concern in the country in that year. 495 cases showed no concern for this issue in the country in the given year. As with greed variable, those things leading to grievance may take time to fully cause the population or the state to take violent action. A drought may last only a year before policy is enacted that protects farmers from its ill effects, or after two years no action may have been taken to protect the farmers and they may decide it is necessary to take up arms against the state for the purpose of protecting their lives. Thus, with these variables we also include lagged variables of one and two years that are tested in our models. Control Variables Our independent variables do not exist in a vacuum. Other factors must be considered as cause and correlates of civil war. We consider four factors that have been used for a variety of reasons with a variety of results in previous studies of civil war. 10 Polity This variable is the squared value of the standard polity score generated by adding the Polity IV autocracy and democracy values. It is squared because this allows us to see the U-shaped relation of governmental type with respect to conflict. Those states that are highly autocratic and those that are highly democratic are less likely to experience civil war. This has been confirmed in many studies. Gross Domestic Product Per Capita This allows us to test the general economic health of a state. It is based on the measure of GDP in millions of U.S. dollars. This is also a proxy measure in some studies for strength of the state and relates the ability of the state to avoid violent attempts to harm or destroy the state. Ethnic Fractionalization We use the ethnic fractionalization scores as found in Fearon and Laitin (2003). This allows us to control for the amount of ethnic divisiveness in a country being a causal factor in organizing for and engaging in civil violence. Mountainous Terrain This variable measures the estimated percentage of mountainous terrain in a country in a given year. This measure is taken from Fearon and Laitin (2003). It is argued that rebel groups are more likely to form and actively challenge the government to a greater extent when mountainous terrain exists for the rebels to return to for protection from government action. This argument is made more poignant by the use of terrain by terrorists and tribesmen in the Afghanistan and Pakistan border regions. Lagged Dependent Variables We also include lags of the dependent variables in the models. It is always likely, and hardly ever found not statistically significant, that civil war in the previous year (or duration, or magnitude) is related to civil war in the current year. Statistical Analysis We employ a series of models that are in two formats. As civil war onset is dichotomous, we use logit models to test the independent variables in relation to onset. Both civil war duration and civil war magnitude are interval-ratio level variables and allow us the use regression modeling. Our data are time-series and cross sectional, however, the year panels are not equal for every country (since, for instance, Angola was not independent until 1975 there are 26 cases for Angola and since Nigeria existed independently in 1970 there are 31 cases for Nigeria). To correct for this we use a generalized model that employs panel corrected standard errors. The panel corrected standard error time series 11 regression model creates robust standard errors for the models enhancing the quality of the results. Models 1 through 4, reported in Table 1 are for the logit models with civil war onset as the dependent variable.7 Model 1 includes only the current year independent variables. Model 2 employs the one year lag independent variables. Model 3 employs the two year lag independent variables and model 4 includes the current year and both one and two year lag variables.8 Model 1 includes 1165 country-year observations. The Log Ratio Χ2 is 580.96 with a probability of .0000 and a Pseudo R2 of .5935.9 Of the independent variables tested, only freshwater scarcity was found statistically significant and then only at the .10 level. The control findings were consistent with findings in previous studies indicating that rebel groups consider having terrain that is favorable for hiding and defense against superior armed forces a plus when initiating a civil war and that civil wars generally will not occur in highly democratic or highly autocratic states. Model 2 includes 1163 country-year observations. The Log Ratio Χ2 is 580.21 with a probability of .0000 and a Pseudo R2 of .5932. None of the independent variables tested showed statistical significance in relation to civil war onset. As with model 1 the control variables showed consistency with previous studies of civil war onset. The preliminary indication of this model is that what occurred one year prior to the civil war onset is not correlated or causal to the event. Model 3 includes 1122 country-year observations. The Log Ratio Χ2 is 565.31 with a probability of .0000 and a Pseudo R2 of .5944. In the same pattern as model 2, the independent variables showed not statistically significant relationships with civil war. The control variables remained consistent in significance and in the indicated direction of the relationships. The indication of this model is that resource production and issues from 2 years prior to the event are not correlated with the onset of civil war. Model 4 includes 1120 country-year observations. The Log Ratio Χ2 is 566.78 with a probability of .0000 and a Pseudo R2 of .5964. As with the first three models the independent variables show no statistical significance in 7 Tables are located in Appendix 1. 1 and 2 year lags for fuel production greater than 33% of export GDP and diamond production were dropped due to collinearity with the initial variable from which they were derived. Likewise, sxp lagged 1 year was also dropped due to collinearity with sxp. 9 We do not report the Pseudo R-sq. here as a means of showing fit or explained variance, as this cannot be done with this statistic. The Pseudo R-Sq used in our models is a count Pseudo R-Sq. which ranges 0-1, in each of our four logit models the Pseudo R-sq. of the final version of the model is greater than .5 and a larger value than any of the other iterations of the model we considered. 8 12 relation to civil war and the control variables are in keeping with the findings of existing scholarship. Models 5 through 8 are the time-series regressions with civil war duration as the dependent variable with the independent variables done in the same manner as in models 1 through 4. These results are shown in Table 2.10 Model 5, looks at measurements taken in the particular year in relation to duration in that year and includes 1164 observations. The R2 for this model is .6873, meaning nearly 69% of variance in civil war duration as measured (number of months in this year that the conflict lasted) is explained by the included independent variables. The Wald Χ2 for the model is 741.80 with probability .0000 indicating a well specified model. Oil producing states and having fuel exports greater than 33% of export GDP were both statistically significant in relation to civil war duration. Being an oil producing state was negative in its direction and 33% or greater export was positive in its direction. Among the grievance variables freshwater scarcity was statistically significant but was negative in its direction. GDP Per Capita was significant and negative in direction. Civil war onset, civil war magnitude, and the duration of civil war in the previous calendar year were all statistically significant in relation to civil war duration in the given country in the given year. Interestingly civil war onset is negatively related to civil war duration in this model. If each value of each independent variable is held at its value of central tendency, the value of Civil War Duration would equal -2.36 months. In short, it appears civil war is so rare even in one of the world’s most civil war prone areas that duration is non-existent.11 Model 6, which uses one year lags of the independent variables in relation to duration in that year, includes 1162 observations. The R2 for this model is .6874, meaning nearly 69% of variance in civil war duration as measured (number of months in this year that the conflict lasted) is explained by the included independent variables. The Wald Χ2 for the model is 733.35 with probability .0000 indicating a well specified model. Oil production and fuel exports greater than 33% were both statistically significant in model 6, with oil production still being negative in direction. No other independent variables were statistically significant. GDP Per Capita and Civil War Onset showed negative relationship with duration, and Civil War Magnitude and the lag of Civil War Duration were both positive and statistically significant in their relationships with civil war duration. When all of the 10 11 See fn 8. Equations for models 5-12 are expressed in Appendix 2. 13 statistically significant variables were held at their measure of central tendency, the value of civil war duration in model 6 is 7.7690 months. This indicates that with duration past events do have a greater impact than current events. Model 7, using two year lags of the independent variables, includes 1121 observations. The R2 for this model is .6888, meaning nearly 69% of variance in civil war duration as measured (number of months in this year that the conflict lasted) is explained by the included independent variables. The Wald Χ2 for the model is 752.98 with probability .0000 indicating a well specified model. The same variables that were significant in model 6 are significant in model 7. The difference being here they are 2 year lags instead of one year lags. The directions of the indicated relations remain the same. When all of the independent variables are held at their measures of central tendency, the value of civil war duration is 8.4063 months adding more credence to the finding that events in previous years has greater impact on civil war duration than the events of the current year. Model 8 uses current year values plus the 1 and 2 year lag values of the independent variables and includes 1119 observations. The R2 for this model is .6892, meaning nearly 69% of variance in civil war duration as measured (number of months in this year that the conflict lasted) is explained by the included independent variables. The Wald Χ2 for the model is 753.90 with probability .0000 indicating a well specified model. The same variables that were significant in the earlier models remained significant in this model and maintain the same direction of the relationship. Freshwater scarcity did not reenter the equation in this model, an interesting finding that will be discussed in the conclusions. When all of the independent variables are held at their measures of central tendency, the value of civil war duration is 8.5082 months adding more credence to the finding that events in previous years has greater impact on civil war duration than the events of the current year. Table 3 records the results for models using civil war magnitude as the dependent variable. As with the other models we test current and lead year variables separately and then in a combined model.12 Model 9 uses current year values for the independent variables and has 1163 observations. The R2 for this model is .7020, meaning slightly more than 70% of variance in civil war magnitude is explained by the included independent variables. The Wald Χ2 for the model is 694.84 with probability .0000 indicating a well specified model. 12 See fn 8. 14 No grievance variable is significant in model 9, whole only one of the greed variables is significant—loss of forested land. The direction of the relationship is negative indicating as timbering activity increased the number of battle deaths per year decreased. Among the controls used polity-squared, ethnic fractionalization, civil war onset, civil war duration, and the lag of civil war magnitude were positively correlated and statistically significant The findings regarding polity-squared and ethnic fractionalization are interesting. Both highly autocratic regimes and highly democratic regimes can expect higher magnitude civil war. Sub-Saharan African countries that have lower heterogeneity of ethnicity can expect to have civil wars of greater magnitude. If all of the statistically significant variables are held at their measure of central tendency the magnitude of civil war on average would be 305.0559 or roughly 300 battle deaths per year per country in Sub-Saharan Africa. Model 10 uses 1 year lag values for the independent variables and has 1161 observations. The R2 for this model is .7001, meaning slightly more than 70% of variance in civil war magnitude is explained by the included independent variables. The Wald Χ2 for the model is 682.44 with probability .0000 indicating a well specified model. In this model only the same control variables that were significant in model 9 are significant. None of the greed or grievance variables showed significance. If all of the statistically significant variables are held at their measure of central tendency the magnitude of civil war on average would be 459.9097 or roughly 456 battle deaths per year per country in Sub-Saharan Africa. Model 11 uses 2 year lag values for the independent variables and has 1120 observations. The R2 for this model is .7019, meaning slightly more than 70% of variance in civil war magnitude is explained by the included independent variables. The Wald Χ2 for the model is 685.93 with probability .0000 indicating a well specified model. One greed variable, sxp, and one grievance variable, lost arable land, are statistically significant when we consider a two year lag of their value in relation to current year civil war magnitude. The value of sxp is negative in directional relation to magnitude indicating that increased export value of primary commodities in previous years leads to lower numbers of battle deaths during a civil war in the current year. The value of lost arable land is positive in relationship to magnitude. A probable implication of the arable land finding is that it takes time for grievance caused by land loss to manifest in human action. The same control variables were significant in this model as in the previous magnitude models. If all of the statistically significant variables are held at their 15 measure of central tendency the magnitude of civil war on average would be 466.5636 or roughly 467 battle deaths per year per country in Sub-Saharan Africa. Model 12 uses 1 and 2 year lag values as wells as the current year values of the independent variables and has 1118 observations. The R2 for this model is .7057, meaning slightly more than 70% of variance in civil war magnitude is explained by the included independent variables. The Wald Χ2 for the model is 735.63 with probability .0000 indicating a well specified model. One greed variable remains statistically significant in this full model. Lost forested land remained significant and negative in direction with respect to civil war magnitude. Two grievance variables were statistically significant, the two year lag of lost arable land and the current year freshwater scarcity. Both of these are positively correlated with civil war duration. What is indicated by this combination is that the past loss of arable land couples with current freshwater scarcity to increase the level of grievance mobilization into armed conflict. The control variables found significant in models 9-11 remained significant and in the same direction in model 12. The overall model indicates an average value of 1117.5872, or roughly 1118 battle deaths per year per country when the significant variables are held constant at their central tendency. Conclusions Based on findings from our models the data we have tested do not support hypotheses dealing with the onset of civil war from either the greed or grievance perspective. Our hypotheses regarding civil war duration are both supported and contradicted in relation to greed and not supported at all for grievance. The test of greed and grievance is split again with civil war magnitude with greed not being supported or being directly contradicted and grievance finding a strong measure of support. These findings are summarized in Table 4 in relation to the offered hypotheses. TABLE 4: Summary of Findings in Relation to Hypotheses Hypothesis Greed Grievance Civil War Onset + Civil War -+ Duration Civil War --+++ Magnitude + is positive correlation with this measure of civil war, - is negative correlation 16 Given the number of variations on each of the variables used, there were 28 chances for greed to have positive or negative relation with each measurement of civil war used. In our models greed was negatively more often than positively correlated. There were 12 chances for grievance to be positively or negatively related to civil war. Grievance was positively related four times and negatively related one time. The most interesting set of findings is in relation to civil war magnitude. Here greed causes magnitude to diminish and grievance causes magnitude to increase. It is in the area of civil war magnitude that we also have our most robust results in relation to the hypotheses offered. To be sure, civil war is a difficult subject to explain in great detail. What we believe we have found are unique processes that shed light on how we look at intrastate political violence. Civil wars are processes not just brush fires that start quickly, burn hot and then die out as quickly as they start. On the contrary, civil wars are processes and as such we have utilized models that take this into account. We believe that our examination of natural resources and civil war provides a way to unlock the civil war process on a different level than has been accomplished in previous studies. Specifically we find that lost land, lost forests and less fresh water are indeed important but are not immediately important. This seems to indicate that immediate needs are not only important but are important in the long-term. For example, subsistence farmers may be able to survive one year having been pushed from their land but not two, thus they have a grievance since they probably have no other form of income or skills to earn a living. They would also have a grievance if they cannot return to their land. Conversely the “greed” hypothesis would indicate that the possession of large amounts of land is an initiating factor in civil war, however this would only be true in capital intensive agricultural societies where large amounts of land can be exploited by a handful of people. A counter-argument would be that it is not the production but the exports of these products that creates the conditions for greedy people to expropriate them for their own gain. However, the composition of the greed variable SXP is skewed heavily toward non-renewable products and non-foodstuffs. Thus our findings on lost arable land and water scarcity as important components of the conflict process reinforce the grievance hypothesis since they are both immediate and long-term elements of agricultural production. As for urban dwellers loss of land is not important but the ability to purchase food certainly is. They might have grievances if the government cannot provide access to food; however this is different from greed. 17 In sum, our findings seem to confirm that the grievance hypothesis is a stronger explanation and predictor for civil war than the greed hypothesis. The results indicating the importance of the magnitude of civil war is an important innovation has been shown to be significant especially with renewable resource variables. This finding indicates that the processes that start civil wars are complex and have an indeterminate lead time. 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Ann Arbor, MI: Inter-Univeristy Consortium for Political and Social Research. 22 APPENDIX 1: TABLES TABLE 1: CIVIL WAR ONSET Variables Oil Producing State Fuel Production > 33% export GDP Model 1 -.0121 .3926 .4848 .5235 Model 2 .0189 .3914 .6389 .5344 2 Yr Lag .1042 .3617 .0936 .3704 .1152 .3604 1 Yr Lag .0883 .3688 2 Yr Lag SXP .0077 .0482 -.2176 6.7223 .0078 .0516 1 Yr Lag .0072 .0394 2 Yr Lag Lost Forested Land -.0115 .1113 .0455 .1079 1 Yr Lag .0001 .0077 2 Yr Lag Lost Arable Land -.0951 .1357 .0753 .0886 1 Yr Lag .0581 .0977 2 Yr Lag Freshwater Scarcity .4462* .3116 .3797 .3089 1 Yr Lag 2 Yr Lag GDP Per Capita PolitySquared Ethnic Fractionalization Mountainous Terrain Lag of Civil War Onset Constant Model 4 -.0504 .4043 .6424 .5407 .4950 .5200 1 Yr Lag Diamond Production Model 3 -.0390 .4016 -.00001 .0001 -.0012** .0004 .4879 .9154 .0153** .0075 4.7867*** .2889 -4.2752*** .7836 -.00006 .0001 -.0011** .0004 .4487 .9206 .0149** .0075 4.7919*** .2898 -4.2683*** .7853 .3593 .3113 -.00006 .0001 -.0012** .0004 .6404 .9386 .0130* .0076 4.7964*** .2931 -4.3298*** .8027 .2247 6.7223 -.0200 .1119 .0462 .1084 .0001 .0081 -.1032 .1363 .0758 .0901 .0576 .0966 .7619 .9360 -.6880 1.4008 .3297 1.1369 -.00007 .0001 -.0011** .0003 .6629 .9444 .0128* .0076 4.8236*** .3002 -4.3992*** .8092 Top number in each cell is coefficient, bottom number is standard error. *p > .1, ** p > .05, *** p > .001 23 TABLE 2: Civil War Duration Variables Oil Producing State Fuel Production > 33% export GDP Model 5 -24.3139* 13.7244 Model 6 -24.2982* 13.71412 35.8770** 17.7678 39.9815** 18.6264 38.8162** 18.4573 2 Yr Lag 4.6366 12.9408 5.9756 13.5416 4.6254 12.9563 1 Yr Lag 5.8398 13.4490 2 Yr Lag SXP -.0097 .0071 -40.7349 76.3465 -.0098 .0072 1 Yr Lag -.0111 .0075 2 Yr Lag Lost Forested Land -.2089 2.5816 .0011 .0153 1 Yr Lag -.0043 .0164 2 Yr Lag Lost Arable Land 1.2981 2.5138 2.1399 2.5745 1 Yr Lag -.2649 2.6771 2 Yr Lag Freshwater Scarcity 1 Yr Lag 2 Yr Lag Model 8 -27.4782* 14.1809 36.0669* 17.7716 1 Yr Lag Diamond Production Model 7 -27.5212* 14.1489 -10.021* 6.4143 -9.9663 6.3621 -10.3114 6.5658 40.7227 76.3469 -.3621 2.6831 1.6265 2.6315 -.0039 .0169 1.0594 2.5412 2.0622 2.5842 -.4545 2.6536 -6.4333 17.4674 -2.4785 22.7877 -2.026 17.6488 24 TABLE 2: Civil War Duration (Continued) Variables GDP Per Capita PolitySquared Ethnic Fractionalization Mountainous Terrain Civil War Onset Civil War Magnitude Lag of Civil War Duration Constant Model 5 -.0064* .0038 -.0099 .0157 -16.3275 34.2062 -.00009 .3007 -163.342*** 20.5912 .0116*** .0018 .7373*** .0456 31.1538 29.1407 Model 6 -.0063* .0038 -.0101 .01567 -16.5666 34.3471 .0024 .3046 -163.5275*** 20.6362 .0116*** .0018 .7370*** .0457 30.8674 29.1844 Model 7 -.0066* .0039 -.0119 .0159 -15.7704 35.5866 .0022 .3144 -168.9332*** 21.4597 .0119*** .0018 .7325*** .0466 31.7913 30.3051 Model 8 -.0066* .0039 -.0122 .0159 -16.2562 35.4882 -.0108 .3133 -169.6368*** 21.5442 .0119*** .0018 .7319*** .0464 31.8742* 30.1682 Top number in each cell is coefficient, bottom number is standard error. *p > .1, ** p > .05, *** p > .001 25 TABLE 3: Civil War Magnitude Variables Oil Producing State Fuel Production > 33% export GDP Model 9 62.4807 102.4037 Model 10 65.0846 102.1888 -151.3944 272.989 -198.8436 294.6382 -185.1261 287.7116 2 Yr Lag -60.0832 121.8249 -92.4155 125.3395 -71.2676 121.5836 1 Yr Lag -99.0411 125.3938 2 Yr Lag SXP -.03918 .0627 1121.734 1740.686 -.0807 .0617 1 Yr Lag -.1042* .0634 2 Yr Lag Lost Forested Land -101.4269** 48.5619 -.1712 .1766 1 Yr Lag -.1226 .1962 2 Yr Lag Lost Arable Land -17.3386 34.5299 -4.5492 34.5164 1 Yr Lag 133.2197*** 27.822 2 Yr Lag Freshwater Scarcity 1 Yr Lag 2 Yr Lag Model 12 101.0414 103.5762 -174.4339 273.1208 1 Yr Lag Diamond Production Model 11 104.0218 103.7207 81.6495 103.7291 20.5242 104.7026 -3.4474 110.1319 -1121.778 1740.682 -119.4112** 50.7262 -31.9891 50.5032 -.1048 .3270 -32.8543 28.0738 -9.0277 27.2523 141.9307*** 28.3108 657.4915** 269.2569 -412.2042 350.5822 -223.3321 279.2877 26 TABLE 3: Civil War Magnitude (Continued) Variables GDP Per Capita PolitySquared Ethnic Fractionalization Mountainous Terrain Lag Civil War Magnitude Civil War Onset Civil War Duration Constant Model 9 -.0022 .0354 .5738** .2551 473.9728* 253.1283 3.2577 2.5323 .6555*** .0534 2219.388*** 342.6417 1.7949*** .3821 -421.8676** 197.3726 Model 10 .0045 .0358 .5822** .2547 486.4529* 258.2397 3.0793 2.5643 .6537*** .0535 2240.864*** 343.0118 1.7892*** .3808 -424.4516** 198.8118 Model 11 .0088 .0371 .5885** .2847 479.4923* 263.3079 2.5251 2.8199 .6549*** .0545 2253.604*** 356.4664 1.7924*** .3935 -438.6012** 205.7979 Model 12 .0065 .0370 .5770** .2479 464.7894* 257.9229 2.8067 2.8371 .6585*** .0540 2237.556*** 354.2981 1.7812*** .3937 -413.3164** 205.7858 Top number in each cell is coefficient, bottom number is standard error. *p > .1, ** p > .05, *** p > .001 27 APPENDIX 2 FORMULAS FOR REGRESSION LINES The formulas include only those variables that were found statistically significant in relation to the dependent variable. CIVIL WAR DURATION: Models 5 through 8 Model 5: Current Year Value of IVs Civil War Duration = 31.1538 + βOil Producing State + βFuel Production <33% of Export GDP + βFreshwater Scarcity/Pollution + βGDP Per Capita + βCivil War Onset + βCivil War Magnitude + βLag of Civil War Duration Civil War Duration = 31.1538 – 24.3139(0) + 35.8770(0) -10.021(1) - .0064(1195.29) 163.342(0) + .0116(641.988) + .7373(-31.5846) Model 6: 1 Year Lags of IVs Civil War Duration = 30.8674 + βOil Producing State + βFuel Production <33% of Export GDP + βGDP Per Capita + βCivil War Onset + βCivil War Magnitude + βLag of Civil War Duration Civil War Duration = 30.8674 – 24.2982(0) + 36.0669(0) - .0063(1195.29) 163.5275(0) + .0116(641.988) + .7370(-31.5846) Model 7: 2 Year Lags of IVs Civil War Duration = 31.7913 + βOil Producing State + βFuel Production <33% of Export GDP + βGDP Per Capita + βCivil War Onset + βCivil War Magnitude + βLag of Civil War Duration Civil War Duration = 31.7913 – 27.5212(0) + 38.8162(0) - .0066(1195.29) 168.9332(0) + .0119(641.988) + .7325(-31.5846) Model 8: Current Year, 1 Year Lag, 2 Year Lag IVs 28 Civil War Duration = 31.8742 + βOil Producing State + βFuel Production <33% of Export GDP in current year+ βGDP Per Capita + βCivil War Onset + βCivil War Magnitude + βLag of Civil War Duration Civil War Duration = 31.8742 – 27.782(0) + 39.9815(0) - .0066(1195.29) -169.6368(0) + .0119(641.988) + .7319(-31.5846) CIVIL WAR MAGNITUDE: Models 9 though 12 Model 9: Current Year Value of IVs Civil War Magnitude = -421.8676 + βLost Forested Land + βPolity-squared + βEthnic Fractionalization + βLag of Civil War Magnitude + βCivil War Onset + βCivil War Duration Civil War Magnitude = -421.8676 – 101.4269(.2216) + .5738(44.911) + 473.9728(.7343) + .6555(669.726) + 2219.388(0) - 1.7949(35.3297) Model 10: 1 Year Lag Values of IVs Civil War Magnitude = -424.4516 + βPolity-squared + βEthnic Fractionalization + βLag of Civil War Magnitude + βCivil War Onset + βCivil War Duration Civil War Magnitude = -424.4516 + .5822(44.911) + 486.4529(.7343) + .6537(669.726) + 2240.864(0) + 1.7892(35.3297) Model 11: 2 Year Lag Values of IVs Civil War Magnitude = -438.6012 - βSXP + βLost Arable Land + βPolity-squared + βEthnic Fractionalization + βLag of Civil War Magnitude + βCivil War Onset + βCivil War Duration Civil War Magnitude = -438.6012 - .1042(30.9045) + 133.2197(.2064) + .5885(44.911) + 479.4923(.7343) + .6549(669.726) + 2253.604(0) + 1.7924(35.3297) Model 12: Current Year, 1 Year Lag, 2 Year Lag IVs 29 Civil War Magnitude = -413.3164 – βLost Forested Land + βLost Arable Land 2 Year Lag + βFreshwater Scarcity + βPolity-squared + βEthnic Fractionalization + βLag of Civil War Magnitude + βCivil War Onset + βCivil War Duration Civil War Magnitude = -413.3164 – 119.4112(.2264) + 141.9307(.2064) + 657.4915(1) + .5770(44.911) + 464.7894(.7343) + .6585(669.726) + 2237.556(0) + 1.7812(35.3297) 30
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