Appendix and Supplementary Materials: These materials are organized into several parts. In the first part, we discuss the way in which the dataset is constructed and how we measure each of the different concepts in our paper. In Part Two, we include two tables in which we specify the model reported in our paper using two alternative modeling methods: Multi-Level Modeling and Fixed Effects Regression. We report these models by region and with all regions included. In Part Three, we furnish a series of tables in which we include one additional control variable at a time in our model, using the ARFIMA Technique. In Part Four, we display a correlation matrix between the variables that were utilized in our model and the additional control variables that we did not report in our manuscript. In Part Five, we run our models with both country and year binaries at the same time. This is the same model that is reported in the paper, just with country binaries in addition to year-level binaries. In Part Six, we run our models using the ARFIMA-MLM, Multi-Level Modeling, and Fixed Effects Regression techniques with temperature as our only independent variable. In Part Seven, we provide summary statistics for all of the variables used in our analysis. Part One-Dataset Construction and Measurement: Below readers may examine how we constructed our data set comprised of Countries' homicide rates, temperature readings and various control factors. We discuss the key aspects and sources of each type of data included in our final data set, which is available here (link). Construction of Variables: I. Dependent variable: Homicide vars. "homicide", "homiciderate", and "loghom" Homicide data between 1995 and 2012 were collected from the UN as they are slightly more complete for non-western nations than WHO data. Although one might go back further than 1995 data quickly become imbalanced before that era (leading to an overrepresentation of industrialized nations). What is more earlier waves of UN data exist they do not appear fully compatible as visual breaks in the data (large spikes or declines) were present. The original data may be found here: Set one is composed of most recent data (2000-2012), and can be found athttp://www.unodc.org/gsh/en/data.html . The second and third dataset were drawn from UN's 6th and 7th wave of law enforcement and can both be found here: http://www.unodc.org/pdf/crime/seventh_survey/7th%20all%20040331.xls (1998-2000) http://www.unodc.org/pdf/crime/sixthsurvey/cs_2001_06_27.xls (1995-1997) Website accessed 10-6-2014 Since collection of this data a new web interface has been posted at which all data from this time period can be found (http://data.un.org/Data.aspx?d=UNODC&f=tableCode%3a1) Homicide statistics from the UN are a blend of criminal justice (typically law enforcement) and public health data sources, with CJ sources dominant. Although many nations had at least some data available in our time period (1995-2012) we used the following selection criteria for inclusion: (1) Uninterrupted series of at least 8 years of data. (2) A minimum of about 30 homicides per year, nations with 0 homicides in any given year were excluded. (3) Homicides should not display unreasonably large breaks between years (evidence of reporting/definitional change). This is arguably a somewhat subjective rule, but it was used to ensure that data were reported in a stable fashion. (4) Avoiding nations with known political bias in reporting. Nations such as China, who -for at least part of the time period under investigation- are known for underreporting or otherwise distorting the true nature of crime were excluded. Raw homicide data (var. "homicide") were combined with population figures (var "totalpop") from the World Bank data (described below) to calculate rates per 100,000 (var. "homiciderate"). The natural log of var. homiciderate ("lnhomiciderate") was used in the analysis II. Independent variable: Temperature, var. "tempcelcius" The approach to collect temperature data follows that by Rotton and Cohn (2003) and Anderson and DeLisi (2011) who selected the largest cities of each US state to develop a representative sample for their study on US crime rates and climate change. In our case we select the largest city (in some cases, cities) in a nation as homicides tend to cluster in large metropolitan areas. In some cases we select multiple cities and combined the temperature readings based on population weight for those cities (India and the US). The rationale behind selecting one city or a couple of places rather than use the temperature average for the entire nation rest on the realization that violence is highly concentrated in "socially disorganized communities" (Mares 2013b), most typically larger urban places. In order to establish the most reasonable relationship between climate and violence that relation has to be characterized as geographically accurate as possible. Temperature data were drawn from NOAA's Global Historical Climatology Network (GHCN). Monthly Mean Temperature data were aggregated to create average annual temperatures. Any missing values were interpolated using linear interpolation. Original temperature data may be found here: http://gis.ncdc.noaa.gov/map/viewer/#app=cdo&cfg=cdo&theme=monthly&layers=1 Accessed 10-6-2014 In particular, our way of identifying places was by examining the sizes of the largest cities in a nation. If a country has a dominant city (more than 2x population of next largest city) that one city would suffice, unless the nation has a very large total population (100 million plus), or extensive landmass with much climatic variation. In those cases we would seek out additional large places and weigh temperature data according to population sizes. In some cases measurement stations were not in or near our cities. Our preferences obviously was to keep stations located within a few miles of the cities, in a few cases we had to use locations over 60 miles from the city in question, but we this would only be used if climatic conditions would be reasonably identical (such as locations on the coast, for instance). In some cases nations had to be dropped because no reasonable nearby locations could be identified, or too many missing data were present in the data. Nations for which approach was followed and city/cities for which temperature data were collected (not all ended up being included as temperature data may have been incomplete, other data may have been missing necessitating deletion of nation): Kenya: Nairobi and Mombassa Uganda: Kampala Algeria: Algiers Egypt: Elat, Israel Morocco: Casablanca South Africa: Cape Town, Johannesburg, Durban Sierra Leone: Freetown Bahamas: Nassau Barbados: Barbados Jamaica: Montego Bay Belize: Felipe Carrillo Pue, Mexico Costa Rica: Puerto Limon El Salvador: San Salvador Honduras: Teguciagalpa Mexico: Mexico City and Monterrey Argentina: Mercedes, Uruguay; Cordoba and Rosario Bolivia: Tarija Chile: Curico (located between Santiago, Conception and Valpraiso) Colombia: Bogotá and Cali (Medellin not available) Ecuador: Pichilingue (between Guyaquil and Quito, only available) Guyana: Tumeremo, Venezuela Paraguay: Concepcuion (few in centre) Peru: Arequipa. Site reflects climatic conditions of Lima (near ocean), but slightly more south. Uruguay: Rocha, (nearest to Montevideo). Venezuela: Maracay B.A. Sucr. (Between Caracas and Valencia) Kazakhstan: Almaty Tajikistan: Dushanbe Hong Kong: Shanwei, China Japan: Tokyo and Nara (near Kyoto, Kobe, Osaka) Mongolia: Bulgan (closest to Ulan Batar) Philippines: Manilla Singapore: Sitiawan, Malaysia Thailand: Bangkok Bangladesh: Agartala, India (east of Dhaka) India: New Delhi, Mumbai, Calcutta Pakistan: Bhuj Rudramata, India (near Karachi): Lahore Sri Lanka: Hambantota (Southeast of Colombo) Armenia: Amasia (West of Yerevan) Azerbaijan: Alat (Southwest of Baku) Georgia: Bolnisi (Southwest of Tbilsi) Belarus: Mariyna Gorka (Southeast of Minsk) Czech Republic: Milesovka (Northeast of Prague) Hungary: Hurbanovo (West of Budapest) Poland: Siedlce (East of Warsaw -only available) Moldova: Kisinev Romania: Varfu Omul (Northwest of Bucharest) Denmark: Copenhagen Estonia: Tallinn Finland: Helsinki, dominant Ireland: Dublin Lithuania: Vilnius and Kanaus Norway: Oslo Sweden: Linkoeping (Southwest of Stockholm) United Kingdom: Cet Central (near Birmingham) Greece: Hellinikon Italy: Rome and Verona Portugal: Porto Serbia: Belgrade Spain: Navacerrada (Madrid) and Barcelona Macedonia: Lazaropole (Southwest of Skopje) Austria: Vienna Belgium: Brussels France: Paris Germany: Köln, Berlin, Munich Netherlands: De Bilt (near Utrecht) Switzerland: Zurich, and Geneva Australia: Perth, Adelaide, Sydney United States: New York, Los Angeles, Chicago Canada: Toronto New Zealand: Wellington Nations ultimately included in our analysis: Algeria, Australia, Austria, Bahamas, Bangladesh, Barbados, Belgium, Belize, Canada, Colombia, Costa Rica, Czech Republic, Egypt, El Salvador, Estonia, Finland, France, Germany, Greece, Honduras, Hungary, India, Ireland, Italy, Jamaica, Japan, Kazakhstan, Kenya, Lithuania, Macedonia, Mexico, Moldova, Mongolia, Morocco, Netherlands, New Zealand, Norway, Pakistan, Paraguay, Philippines, Poland, Portugal, Romania, Serbia, Singapore, South Africa, Spain, Sri Lanka, Sweden, Switzerland, Tajikistan, Thailand, Uganda, United Kingdom, Uruguay, United States, Venezuela III. Control Variables Multiple control variables were vetted, but many were not available for developing nations, restricting our opportunities to utilize them for all nations in the sample Used in manuscript: 1. Population: var "totalpop" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 Measure reflects total annual population as estimated or by census. Used to compute homicide rates, not included separately in analysis. 2. Consumer Price Index: var. "cpi" and “cpidiff” (differenced) Source: World Bank: http://data.worldbank.org/country, accessed 10-6-2014 From File Meta Data: "Consumer price index (2010 = 100). Consumer price index reflects changes in the cost to the average consumer of acquiring a basket of goods and services that may be fixed or changed at specified intervals, such as yearly. The Laspeyres formula is generally used." CPI was used to reflect the immediacy with which price hikes may affect violence levels 3. Infant mortality: var. "mortalityinfant" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 From File Meta Data : " Infant mortality rate is the number of infants dying before reaching one year of age, per 1,000 live births in a given year." 4. Youth Unemployment: vars. "maleyouthunemployed" and "unemdiff” (differenced) Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 From File meta Data: "Unemployment, male youth total (% of total labor force ages 15-24) (modeled ILO estimate). Youth unemployment refers to the share of the labor force ages 15-24 without work but available for and seeking employment." Male youth unemployment rather than all unemployment is used because it affects the group at highest risk for offending and victimization in homicides. We expect that variation in homicide would be most affected by young males, the available time that youth have to spend on delinquent activity, including violence, may be impacted by their unemployment rates. 5. Immigrant Population: var "migrants" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 From File Meta Data: "International migrant stock (% of population) International migrant stock is the number of people born in a country other than that in which they live. It also includes refugees. The data used to estimate the international migrant stock at a particular time are obtained mainly from population censuses. The estimates are derived from the data on foreignborn population--people who have residence in one country but were born in another country. When data on the foreign-born population are not available, data on foreign population--that is, people who are citizens of a country other than the country in which they reside--are used as estimates. After the breakup of the Soviet Union in 1991 people living in one of the newly independent countries who were born in another were classified as international migrants. Estimates of migrant stock in the newly independent states from 1990 on are based on the 1989 census of the Soviet Union. For countries with information on the international migrant stock for at least two points in time, interpolation or extrapolation was used to estimate the international migrant stock on July 1 of the reference years. For countries with only one observation, estimates for the reference years were derived using rates of change in the migrant stock in the years preceding or following the single observation available. A model was used to estimate migrants for countries that had no data." Although the literature on immigrants and violence is certainly somewhat mixed, a recent emerging consensus suggests (Martinez 2014) that migrants may actually lower the incidence of violence in some nations (the US, for instance). For this reason we included the proportion of migrants as a longer term variation. 6. Battle Casualties: vars. "battledeath" and "batdeathrate" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 From File metadata: "Battle-related deaths (number of people) Battle-related deaths are deaths in battle-related conflicts between warring parties in the conflict dyad (two conflict units that are parties to a conflict). Typically, battle-related deaths occur in warfare involving the armed forces of the warring parties. This includes traditional battlefield fighting, guerrilla activities, and all kinds of bombardments of military units, cities, and villages, etc. The targets are usually the military itself and its installations or state institutions and state representatives, but there is often substantial collateral damage in the form of civilians being killed in crossfire, in indiscriminate bombings, etc. All deaths--military as well as civilian--incurred in such situations, are counted as battle-related deaths." Battle related deaths are used to account for any changes in homicide levels that may be linked to group conflicts. Not used in manuscript, but used in alternative specifications in appendix: 1. Income (not used): vars. "income", and "incomediff" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 From File Meta Data: "GNI per capita, Atlas method (current US$) GNI per capita (formerly GNP per capita) is the gross national income, converted to U.S. dollars using the World Bank Atlas method, divided by the midyear population. GNI is the sum of value added by all resident producers plus any product taxes (less subsidies) not included in the valuation of output plus net receipts of primary income (compensation of employees and property income) from abroad. GNI, calculated in national currency, is usually converted to U.S. dollars at official exchange rates for comparisons across economies, although an alternative rate is used when the official exchange rate is judged to diverge by an exceptionally large margin from the rate actually applied in international transactions. To smooth fluctuations in prices and exchange rates, a special Atlas method of conversion is used by the World Bank. This applies a conversion factor that averages the exchange rate for a given year and the two preceding years, adjusted for differences in rates of inflation between the country, and through 2000, the G-5 countries (France, Germany, Japan, the United Kingdom, and the United States). From 2001, these countries include the Euro area, Japan, the United Kingdom, and the United States." Income was dropped from the analysis due to high levels of correlation with multiple other independent variable (especially CPI and Unemployment), thereby potentially distorting some of the results (effects can be seen in alternative specifications below). 2. Prison Population (not used): vars. "prison" and "prisonrate” (rate per 100,000) Sources: United Nations and the International Centre for Prison Studies Since UN data is limited on incarceration we added in data from ICPS to fill gaps. Remaining missing data is interpolated (linear). In general, the prison population is calculated by adding all inmates of local, state and federal prisons/jails together and may include people awaiting trial, and political prisoners. UN Data is obtained through: http://www.unodc.org/documents/data-andanalysis/statistics/crime/CTS2013_Persons_detained.xls (2000-2012) http://www.unodc.org/pdf/crime/seventh_survey/7th%20all%20040331.xls (1998-2000) http://www.unodc.org/pdf/crime/sixthsurvey/cs_2001_06_27.xls (1995-1997) Website accessed 10-6-2014 ICPS data is accessed through: http://www.prisonstudies.org/world-prison-brief Website accessed 10-6-2014 Prison population was dropped from the final analysis as it did not attain significance in all but one model (Europe) and led to a reduction in the overall sample size. 3. Number of Police officers (not used): vars. "Police", “Policerate” (rate per 100,000) Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 While police levels is an interesting variable could not be used as a control variable as the data were not complete enough for our final sample and would have reduced the number of nations in our sample too much. Its effects appear largely negative (more police, fewer homicides) and may thus be seen as one way to mitigate the predicted effects of rising temperatures, but it must be stressed that the data available for this variable is largely limited to Western nations, where climate effects on crime appear lower. 4. Life expectancy at birth (not used): var. "lifeexpectancy" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 Life expectancy is expressed in years. Life expectancy and child mortality, unsurprisingly correlated very highly. We decided to retain child mortality because it is measured as a rate offering slightly greater precision. We also believe the care very young children receive better represents attitudes toward life and ability of nations to preserve life, whereas life expectancy may be biased by the demographic composition of a nation. 5. Urban population (not used): var. "urbanpop" Source: World Bank http://data.worldbank.org/country, accessed 10-6-2014 Urban population is expressed as a percentage of total population. While we do not dispute that urban population growth may be relevant when comparing nations, we do not think that urban growth within nations manifests itself rapidly (in the span of under two decades) alters homicide levels. Nations used in final analysis: The following nations had complete enough data to be utilized in the final analysis: Algeria, Australia, Austria, Bahamas, Bangladesh, Barbados, Belgium, Belize, Canada, Colombia, Costa Rica, Czech Republic, Egypt, El Salvador, Estonia, Finland, France, Germany, Greece, Honduras, Hungary, India, Ireland, Italy, Jamaica, Japan, Kazakhstan, Kenya, Lithuania, Macedonia, Mexico, Moldova, Mongolia, Morocco, Netherlands, New Zealand, Norway, Pakistan, Paraguay, Philippines, Poland, Portugal, Romania, Serbia, Singapore, South Africa, Spain, Sri Lanka, Sweden, Switzerland, Tajikistan, Thailand, Uganda, England and Wales, Uruguay, United States, Venezuela. Part Two-Alternative Modeling Methods: In this section, we specify two alternative routes by which we can model our results: multi-level modeling with fixed and random effects, and fixed effects regression. Table 1. Climate Change and Homicide Rates, Multi-Level Modeling Results Independent Variable All Countries Africa Latin America Asia Former Communist Europe North America/ AUS/NZ .144** (.044) .030 ** (.011) -.006 (.008) .014 (.081) -.066 (.165) .010 (.048) -1.264 (1.591) .069 * (.041) -.004 (.009) .032 * (.014) .065 * (.038) .022 (.043) .139 * (.065) .605 (1.065) -.001 (.024) .007 (.007) .007 (.010) -.000 (.036) -.091*** (.016) .004 (.003) 1.757** (.758) .002 (.012) .001 (.002) .003 (.004) .005 (.017) .005 (.028) .126 (.108) .719*** (.285) .005 (.015) .013 * (.006) .033 ** (.012) -.128 * (.055) -.001 (.013) - .028 *** (.003) -.010 (.015) .050 * (.024) 1.113*** (.047) -.022 ** (.007) -.371 (1.165) -3.133*** (.303) 1.78*10-17 (-) .0003 (-) 2.06*10-22 (-) .021 (-) 7.56*10-19 (-) 1.90*10-20 (-) 1.72*10-15 (-) 3.29*10-25 (-) .001 (-) .006 (-) 5.12*10-23 (-) 1.41*10-23 (-) 1.31*10-21 (-) 2.69*10-27 (-) .0003 (-) .006 (-) 8.75*10-30 (-) 2.59*10-27 (-) 2.83*10-22 (-) 2.40*10-26 (-) 6.22*10-26 (-) .0002 (-) .003 (-) .019 (-) .0004 (.0006) .0002* (.0001) 4.52*10-20 (-) .007* (.004) .0003 (.003) -4 Fixed Effects Parameters 1,2,3,4 Temperature .041*** (.012) Unemployment .007 ** (differenced) (.003) Price Index .017*** (differenced) (.005) Infant Mortality .020 (.022) Migrant -.026 Percentage (.017) Battle Deaths .005 (.004) Constant .488* (.239) Random-Effects Parameters Temperature Unemployment (differenced) Price Index (differenced) Infant Mortality Migrant Percentage Battle Deaths .003* (.001) .0001 (.0001) .0004* (.0002) .013*** (.003) .004* (.002) 2.16 * 10-20 (-) .061 (.266) 3.03*10-22 (-) .0004 (-) 2.97*10-24 (-) 3.49*10-23 (-) 2.01*10-22 (-) 7.73*10-18 (-) Table 1 (Continued). Climate Change and Homicide Rates (Multi-Level Modeling results) Independent Variable All Countries Africa Latin America Asia Former Communist Europe North America/AUS/NZ Variance (Constant) N Chi-Squared Prob>ChiSquared Log-Likelihood 1.077* (.584) 817 105.71 <.0001 4.852 (-) 65 51.63 .0001 1.377 168 56.33 .0001 2.017 (-) 117 152.82 <.0001 .557 (-) 160 271.18 <.0001 .070 (.060) 239 218.12 <.0001 7.29*10-21 (-) 68 4046.81 <.0001 95.718 9.018 -10.513 48.057 87.717 124.807 74.387 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. 3. The values in parenthesis are standard errors. 4. No battle casualties were recorded in included European countries during study period, hence no estimate could be created Table 2. Climate Change and Homicide Rates, Fixed Effects Regression Results Independent Variable All Countries Africa Latin America Asia Former Communist Europe North America /AUS/NZ Temperature 1 .018** 2 (.007) 3 .003* (.002) .006** (.003) .040** (.015) -.031* (.016) .008* (.004) .800*** (.056) 760 5.91 <.0001 .100* (.048) .025** (.009) .002 (.008) -.091* (.042) -.317* (.175) -.003 (.060) 1.695** (.522) 59 3.48 .006 .072*** (.023) .008 (.005) .019** (.006) .010 (.042) .067 (.147) .018 (.048) .886*** (.221) 156 3.40 .004 .016 (.016) .001 (.005) .006 (.006) .022 (.016) -.166*** (.035) .011** (.004) 1.303*** (.162) 108 6.92 <.0001 -.006 (.013) -.0001 (.002) .001 (.005) .089*** (.014) .078** (.031) .056 (.034) -.096 (.119) 149 14.07 <.0001 .022* (.012) .001 (.004) .006 (.009) .134* (.064) -.012 (.016) .001 (.026) .019* (.009) .018 (.015) .666*** (.108) .017 (.017) -.838 (1.248) -2.066** (.650) 64 9.79 <.0001 Unemployment (differenced) Price Index (differenced) Infant Mortality Migrant Percentage Battle Deaths Constant N F-Statistic Prob>F-Statistic 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed test. 3. The values in parenthesis are standard errors. 4. No battle casualties were recorded in included European countries during study period, hence no estimate could be created 4 -.374** (.127) 224 3.19 .009 Part Three-Including One Additional Control at a Time using ARFIMA Table 1. Climate Change and Homicide Rates among All Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .056 *** .056 *** (.012) (..011) Male Youth .003 .002 Unemployment (.002) (.002) Price Index .004 *** .004 *** (.001) (.001) Infant Mortality .0004 .001 (.009) (.008) Migrant Percentage -.004 -.003 (.009) (.009) Battle Deaths .002 .002 (.006) (.006) Income -.007 (.006) Prison Population - Model Three Model Four Model Five Model Six .049 ** (.011) .004 * (.002) .004 *** (.001) .009 (.008) -.007 (.009) .002 (.005) - .035 ** (.011) .003 (.002) .008 *** (.001) .020 (.011) -.004 (.009) .012 (.028) - 054 *** (.011) .004 * (.002) .004 *** (.001) -.011 (.010) -.001 (.009) .001 (.006) - .058 *** (.011) .003 (.002) .004 *** (.001) -.0002 (.009) -.003 (.010) .002 (.006) - - - - -.0000005 (.0000003) - - -.045 * (.016) - Number of Police Officers - .0002 (.0002) - Life Expectancy - - - Urban Population - - - Intercept .049 .033 .022 (.342) (.132) (.419) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept 1.529 1.517 1.458 1.501 (1.529) (1.232) (1.208) (1.225) Year intercept .089 .00006 .034 .144 (.298) (.008) (.185) (.379) N 673 (57 Countries, 666 (57 Countries, 634 (55 Countries, 541 (50 Countries, 13 Years) 13 Years) 13 Years) 13 Years) Log-Likelihood -129.794 -131.715 -85.377 -65.034 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. .040 (.155) .0000001 (.00000009) .052 (.250) 1.299 (1.140) .000000001 (.00003) 673 (57 Countries, 13 Years) -129.564 1.558 (1.248) .033 (.183) 673 (57 Countries, 13 Years) -144.243 3. The values in parenthesis are standard errors Table 2. Climate Change and Homicide Rates among African Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .165 * .168 * (.087) (.092) Male Youth .016 * .016 * Unemployment (.011) (.011) Price Index .015 *** .015 *** (.005) (.005) Infant Mortality -.130 * -.131 * (.075) (.076) Migrant Percentage -.100 -.094 (.190) (.197) Battle Deaths .177 * .176 * (.074) (.075) Income -.021 (.195) Prison Population - Model Three Model Four Model Five Model Six .202 ** (.082) .014 * (.008) .012 * (.004) -.105 * (.065) -.080 (.203) .042 (.054) - .015 (.138) -.053 * (.025) .009 (.007) -.027 (.112) .054 (.056) -.035 (.066) - .080 (.076) .020 * (.010) .023 *** (.004) -.222 *** (.067) -.151 (.162) .160 * (.063) - .121 + (.076) -.004 (.011) .012 *** (.004) -.073 (.071) .154 (.166) .111 * (.067) - - - - -.00003 (.00002) - - -.170 *** (.040) - - Number of Police Officers - - -.003 (.002) - Life Expectancy - - - - Urban Population - - - - Intercept .143 .143 .740 -.001 (.953) (.955) (.944) (.846) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept 5.121 5.137 3.943 6.031 * 10-16 (2.263) (2.266) (1.986) (2.456 * 10-8) Year intercept .032 .034 .036 .013 (.178) (.184) (.191) (.112) N 62 (6 Countries, 62 (6 Countries, 48 (5 Countries, 28 (3 Countries, 13 Years) 13 Years) 13 Years) 12 Years) Log-Likelihood -38.046 -38.764 -22.868 -17.094 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. 3. The values in parenthesis are standard errors .312 (.680) -.161 *** (.042) .091 (1.490) 2.390 (1.546) .046 (.215) 62 (6 Countries, 13 Years) -32.846 12.975 (3.602) .042 (.205) 62 (6 Countries, 13 Years) -35.254 Table 3. Climate Change and Homicide Rates among Asian Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .018 .020 (.031) (.030) Male Youth -.014 -.013 Unemployment (.013) (.013) Price Index .0004 -.0002 (.003) (.003) Infant Mortality -.021 + -.020 + (.014) (.013) Migrant Percentage -.088 *** -.078 *** (.021) (.021) Battle Deaths .001 .002 (.005) (.005) Income -.034 * (.020) Prison Population - Model Three Model Four Model Five Model Six .013 (.030) -.020 + (.013) -.003 (.003) -.026 * (.015) -.075 ** (.024) .001 (.005) - .017 (.043) -.028 * (-.016) .005 (.006) -.007 (.027) -.094 *** (.021) -.126 (.099) - .023 (.019) -.006 (.012) -.001 (.003) -.061 *** (.015) -.040 * (.017) -.0002 (.005) - .010 (.032) -.014 (.013) -.00006 (.003) -.023 * (.015) -.086 *** (.021) .001 (.005) - - - - -.0000001 (.0000004) - - -.222 *** (.044) - - Number of Police Officers - - .001 (.001) - Life Expectancy - - - - Urban Population - - - - Intercept .053 .081 -.011 -.049 (.425) (.447) (.452) (.539) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept 1.342 1.264 1.302 1.790 (1.158) (1.125) (1.141) (1.338) Year intercept .016 .044 .035 .019 (.125) (.211) (.187) (.138) N 99 (9 Countries, 99 (9 Countries, 94 (9 Countries, 64 (8 Countries, 13 Years) 13 Years) 13 Years) 13 Years) Log-Likelihood -23.522 -25.019 -28.838 -30.846 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. 3. The values in parenthesis are standard errors -.028 (.427) -.010 (.011) -.019 (.442) .317 (.563) .138 (.372) 99 (9 Countries, 13 Years) -18.691 1.332 (1.154) .024 (.156) 99 (9 Countries, 13 Years) -26.714 Table 4. Climate Change and Homicide Rates among European Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1 Temperature .018 .018 (.014) (.014) Male Youth .005 * .004 * Unemployment (.002) (.002) Price Index .016 * .016 * (.007) (.007) Infant Mortality -.220 *** -.220 *** (.065) (.065) Migrant Percentage -.029 ** -.029 ** (.010) (.010) Battle Deaths n/a 3 n/a 3 Model Three Model Four Model Five Model Six .021 (.015) .005 * (.002) .021 ** (.008) -.188 *** (.069) -.028 ** (.010) n/a 3 .022 (.015) .005 * (.003) .018 ** (.007) -.212 *** (.066) -.028 ** (.010) n/a 3 .018 (.014) .005 * (.002) .018 ** (.007) -.220 *** (.064) -.026 ** (.010) n/a 3 .023 * (.014) .004 * (.002) .017 ** (.007) -.202 *** (.065) -.026 ** (.010) n/a 3 - - - - - - - -.000001 (.0000008) - - -.068 (.046) - - Income - Prison Population - -.004 (.007) - Number of Police Officers - - -.002 * (.001) - Life Expectancy - - - - Urban Population - - - - Intercept -.127 -.131 -.131 -.128 -.127 (.109) (.142) (.113) (.157) (.119) ARFIMA, Random Effects, variance and standard deviation Country intercept .097 .096 .099 .105 .089 (.311) (.309) (.315) (.324) (.299) Year intercept .003 .012 .004 .016 .006 (.058) (.108) (.062) (.125) (.079) N 183 (15 Countries, 183 (15 Countries, 181 (15 Countries, 181 (15 Countries, 183 (15 Countries, 13 Years) 13 Years) 13 Years) 13 Years) 13 Years) Log-Likelihood 40.058 36.242 33.820 27.116 38.954 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-values. 3. No battle casualties were recorded in included European Countries during study period, hence no estimate could be created .010 + (.007) -.130 (.194) .086 (.293) .030 (.173) 183 (15 Countries, 13 Years) 36.932 Table 5. Climate Change and Homicide Rates among Former Communist Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature -.003 -.001 (.014) (.014) Male Youth -.003 + -.002 Unemployment (.002) (.002) Price Index .003 + .002 (.002) (.002) Infant Mortality .026 + .027 + (.019) (.019) Migrant Percentage .047 ** .048 ** (.019) (.018) Battle Deaths -.001 .002 (.038) (.038) Income .051 * (.031) Prison Population - Model Three Model Four Model Five -.005 (.012) -.004 * (.002) .005 ** (.002) .035 + (.023) .040 ** (.016) -.038 (.033) - -.005 (.013) -.004 * (.002) .005 ** (.002) .020 (.021) .046 ** (.017) -.029 (.033) - -.004 (.014) -.001 (.002) .001 (.002) .004 (.021) .031 * (.020) .009 (.038) - - - -.000001 (.000004) - .097 (.217) -.065 ** (.028) .020 (.198) .434 (.659) .000004 (.002) 114 (10 Countries, 13 Years) 14.235 .396 (.629) .00003 (.005) 131 (11 Countries, 13 Years) 14.109 Number of Police Officers - - -.0004 (.0003) - Life Expectancy - - - Intercept .028 .036 .145 (.210) (.210) (.247) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept .445 .446 .477 (.667) (.668) (.691) Year intercept .0004 .0000004 .008 (.002) (.001) (.091) N 131 (11 Countries, 131 (11 Countries, 117 (10 Countries, 13 Years) 13 Years) 13 Years) Log-Likelihood 14.228 13.002 21.373 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. 3. The values in parenthesis are standard errors Table 6. Climate Change and Homicide Rates among Latin American Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .043 .046 (.044) (.044) Male Youth .010 .013 Unemployment (.009) (.010) Price Index -.005 * -.004 (.003) (.003) Infant Mortality .040 .030 (.033) (.034) Migrant Percentage .012 .017 (.041) (.041) Battle Deaths .264 *** .259 *** (.068) (.068) Income -.033 (.052) Prison Population - Model Three Model Four Model Five Model Six .051 (.044) .009 (.009) -.007 * (.003) .029 (.034) .032 (.043) .260 *** (.067) - -.009 (.050) -.007 (.010) -.005 (.004) .078 * (.044) .052 (.056) .177 (.672) - .048 (.042) .011 (.009) -.005 * (.003) .033 (.035) .005 (.038) .258 *** (.069) - .021 (.048) .013 (.009) -.005 * (.003) .027 (.034) .026 (.044) .270 *** (.067) - - - - -.000006 *** (.000002) - - -.073 (.078) - - Number of Police Officers - - -.0003 (.0003) - Life Expectancy - - - - Urban Population - - - - Intercept -.064 -.064 -.178 -.242 (.375) (.383) (.420) (.452) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept .638 .667 .712 1.708 (.799) (.817) (.844) (1.307) Year intercept .083 .086 .111 .023 (.287) (.294) (.332) (.152) N 146 (12 Countries, 139 (12 Countries, 142 (12 Countries, 102 (10 Countries, 13 Years) 13 Years) 13 Years) 13 Years) Log-Likelihood -56.336 -56.527 -60.573 -47.946 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. 3. The values in parenthesis are standard errors -.064 (.481) -.017 (.013) -.064 (.311) .482 (.694) .186 (.432) 146 (12 Countries, 13 Years) -57.678 .817 (.904) .024 (.154) 146 (12 Countries, 13 Years) -59.038 Table 7. Climate Change and Homicide Rates among North American Countries Independent Variable Model One (Original) Model Two ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .028 ** .028 *** (.009) (.007) Male Youth .009 .007 Unemployment (.010) (.011) Price Index -.014 -.013 (.015) (.016) Infant Mortality 1.078 *** 1.057 *** (.131) (.115) Migrant Percentage -.022 -.026 (.019) (.017) Battle Deaths .249 .353 (1.609) (1.629) Income -.007 (.015) Prison Population - Model Three Model Four Model Five .024 *** (.006) .007 (.009) -.007 (.014) 1.043 *** (.096) .007 (.026) -.186 (1.604) - .032 *** (.007) .007 (.010) -.001 (.018) 1.087 *** (.105) .002 (.028) .033 (1.607) - .028 (.030) .009 (.012) -.013 (.016) -1.093 *** (.275) -.021 (.023) .243 (1.666) - - - -.068 (.050) - - Life Expectancy - - .001 (.0004) - Urban Population - - - Intercept -.156 -.156 -.156 (.121) (.140) (.114) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept .001 .0004 .00001 (.036) (.021) (.00001) Year intercept .012 .017 .010 (.107) (.130) (.102) N 52 (4 Countries, 52 (4 Countries, 52 (4 Countries, 13 Years) 13 Years) 13 Years) Log-Likelihood 9.870 6.700 4.300 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-test. 3. The values in parenthesis are standard errors -.156 (.120) .002 (.065) -.156 (.129) .00001 (.00001) .012 (.108) 52 (4 Countries, 13 Years) 8.687 .002 (.040) .013 (.116) 52 (4 Countries, 13 Years) 8.048 Part Four-Correlation Matrix between Variables Variable Homicide Rates Temperature Unemployment Price Index Infant Morality Migrant Percentage Battle Deaths Income Prison Population Number of Police Officers Life Expectancy Homicide Rates 1.000 Temperature .362 1.000 Unemployment -.008 -.246 1.000 Price Index .317 -.018 .036 1.000 Infant Mortality .467 .394 -.099 -.391 1.000 Migrant Percentage .326 .128 .029 -.173 .291 1.000 Battle Deaths -.354 -.096 -.133 .139 -.394 -.206 1.000 Income -.258 -.152 -.155 .181 -.234 -.085 .221 1.000 Prison Population .462 .135 -.047 -.118 .030 -.092 .223 -.098 1.000 Number of Police Officers .050 .200 -.140 -.025 .429 .017 -.200 -.057 .009 1.000 Life Expectancy -.621 -.271 .034 .448 -.856 -.358 .383 .285 -.223 -.144 1.000 Urban Population -.027 -.339 .063 -.223 .090 -.034 -.175 -.042 .013 -.050 -.102 Urban Population 1.000 Part Five-ARFIMA-MLM Models with Year and Country Binaries Independent Variable All Countries Africa Latin America ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .050 ** .177 * .050 (.014) (.090) (.055) Male Youth .002 .014 .017 * Unemployment (.002) (.011) (.009) Price Index .004** .015 *** -.007 * (.001) (.004) (.002) Infant Mortality -.010 -.171 * -.018 (.010) (.082) (.038) Migrant .010 -.055 .186 ** Percentage (.011) (.199) (.072) Battle Deaths .002 .200 ** .258 *** (.006) (.076) (.068) Intercept -1.240 1.841 -2.089 * (1.310) (1.371) (1.024) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept 1.640 1.230 .838 (1.281) (1.109) (.915) Year intercept .040 .189 .024 (.201) (.435) (.153) N 673 (57 62 (6 Countries, 146 (12 Countries, 13 13 Years) Countries, 13 Years) Years) Log-Likelihood -34.980 -25.788 -38.554 Asia Former Communist Europe North America and Australia .018 (.046) -.018 (.014) -.0003 (.003) -.030 * (.017) -.088 *** (.028) .001 (.005) .247 (1.456) -.004 (.015) -.003 (.002) .003 (.002) .032 (.024) .028 (.021) -.001 (.038) -.260 (.771) .018 (.017) .004 (.003) .014 * (.007) -.252 *** (.070) -.026 * (.013) n/a 4 .035 (.046) .010 (.010) -.011 (.018) .561 (.413) .033 (.036) -.437 (1.632) -.590 (.850) 1.189 (1.090) .027 (.165) 99 (9 Countries, 13 Years) .572 (.756) .012 (.109) 131 (11 Countries, 13 Years) 26.074 .202 (.449) .006 (.075) 183 (15 Countries, 13 Years) 45.271 -9.494 -.037 (.490) 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-values. 3. The values in parenthesis are standard errors. 4. No battle casualties were recorded in included European Countries during study period, hence no estimate could be created. .538 (.734) .010 (.098) 52 (4 Countries, 13 Years) 10.948 Part Six- Models with Temperature as the Sole Independent Variable Table 1: ARFIMA-MLM Models with Temperature as the Sole Independent Variable Independent Variable All Countries Africa Latin America Asia Former Communist Europe North America and Australia .030 (.040) .153 (.495) -.001 (.013) .038 (.292) .008 (.016) .0002 (.036) -.113 (.124) -.156 (.378) ARFIMA-MLM, Fixed-Effects, coefficients and standard error 1,2,3 Temperature .054 *** .211 * .077 * (.011) (.098) (.041) Intercept -.924 * .025 -.064 (.329) (.798) (.309) ARFIMA-MLM, Random Effects, variance and standard deviation Country intercept Year intercept N Log-Likelihood 1.556 (1.248) .043 (.209) 3.206 (1.790) .070 (.264) .691 (.831) .032 (.180) 1.837 (1.356) .043 (.207) .687 (.829) .020 (.140) .119 (.344) .005 (.071) .507 (.712) .013 (.113) 694 (58 Countries, 13 Years) -132.601 62 (6 Countries, 13 Years) 154 (12 Countries, 13 Years) -51.622 112 (10 Countries, 13 Years) -32.231 131 (11 Countries, 13 Years) 28.830 183 (15 Countries, 13 Years) 33.779 52 (4 Countries, 13 Years) -36.655 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed t-values. 3. The values in parenthesis are standard errors. 8.457 Table 2. Multi-Level Models with Temperature as the Sole Independent Variable Independent Variable All Countries Africa Latin America Asia Former Communist Europe North America and Australia .210 ** (.081) -2.790 + (1.782) .044 (.040) 2.107 * (1.002) .032 (.034) .082 (.875) .003 (.022) 1.001 *** (.310) -.011 (.015) .063 (.189) .028 (.036) .329 (.292) .002 (.001) 1.006 (.285) 884 (58 Countries, 18 Years) 196.64 <.0001 2.43 * 10-25 (4.99 * 10-24) 2.591 (1.579) 65 (6 Countries, 18 Years) 4.10 * 10-27 (1.35 * 10-22) 1.516 (.727) 136 (10 Countries, 18 Years) 79.68 <.0001 .001 (.002) .607 (.287) 173 (11 Countries, 18 Years) 345.20 <.0001 2.00 * 10-11 (2.12 * 10-10) .100 (.037) 251 (15 Countries, 18 Years) 186.62 <.0001 .003 (.003) .076 (.188) 72 (4 Countries, 18 Years) 23.60 .072 3.89 * 10-21 (5.10 * 10-20) .626 (.259) 187 (12 Countries, 18 Years) 15.90 .599 -156.78 -23.33 -59.20 -13.25 23.85 87.39 48.87 Fixed Effects Parameters 1,2,3 Temperature .031 ** (.013) Constant .573 ** (.229) Random-Effects Parameters Temperature Variance (Constant) N Chi-Squared Prob>ChiSquared Log-Likelihood 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed test. 3. The values in parenthesis are standard errors. 93.36 <.0001 Table 3. Fixed Effects Regression Models with Temperature as the Sole Independent Variable Independent Variable All Countries Africa Latin America Asia Former Communist Europe North America and Australia Temperature 1 .016 *2 (.007) 3 .946 *** (.026) 826 (58 Countries, 13 Years) 4.78 .029 .072 + (.050) .083 (.264) 59 (6 Countries, 13 Years) .051 ** (.020) 1.935 *** (.102) 175 (12 Countries, 13 Years) 6.18 .014 .039 * (.020) -.171 (.135) 126 (10 Countries, 13 Years) 3.75 .055 -.007 (.012) 1.066 *** (.018) 162 (11 Countries, 13 Years) .41 .524 .013 (.011) -.028 (.037) 236 (15 Countries, 13 Years) 1.37 .243 -.025 (.024) .967 *** (.093) 68 (4 Countries, 13 Years) Constant N F-Statistic Prob>F-Statistic 2.09 .154 1. Fixed effects for each year in the dataset are omitted. 2. +=p<.1, *=p<.05, **=p<.01, and ***=p<.001. All p significance levels based on single-tailed test. 3. The values in parenthesis are standard errors. 1.13 .293 Part Seven- Summary Statistics for Variables in Analyses Table 1: All Countries Variable Mean Standard Deviation Minimum Maximum Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy Urban Population 9.960 16.292 17.200 1.705 8.140 10.340 .207 -2.875 2.500 138.778 30.192 70.200 78.371 10.760 7.895 .399 .672 169.07 73.130 196,573 23.030 10.390 8.340 2.510 1.610 121.290 6.850 1,486,029 2.582 1.10 .150 0 -5.740 27.35 45.970 12 152.656 52.80 40.231 41.614 9.880 880.31 83.480 12,197,105 Mean Standard Deviation Minimum Maximum 14.360 20.180 22.630 19.670 2.790 13.630 .460 17.240 3.200 68.70 27.460 52.000 72.400 22.840 1.450 212.710 .120 171.630 61.650 42.570 24.600 7.130 1.110 494.720 .220 97.990 8.050 19.480 25.310 11.600 .150 0 -.390 55.630 45.970 11.660 135.330 37.400 4.080 3024.000 1.210 399.070 70.910 73.710 Table 2: African Countries SS Variable Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy Urban Population Table 3: Asian Countries Variable Mean Standard Deviation Minimum Maximum Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy 4.450 23.160 11.400 3.500 8.530 4.840 .210 -1.730 2.500 15.750 30.190 28.000 76.690 19.710 8.380 531.710 .340 150.360 71.110 25.060 16.340 14.510 1274.170 1.260 115.600 6.810 16.450 1.100 .300 0 -5.740 27.350 60.190 125.890 52.800 40.230 8413.000 7.710 435.070 83.480 Variable Mean Standard Deviation Minimum Maximum Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy Urban Population 1.290 11.010 16.400 .500 3.220 8.550 .510 4.610 4.200 3.090 19.520 55.500 88.890 3.010 10.140 0 1.360 90.040 79.230 52.960 10.140 .840 4.710 0 2.510 24.220 1.610 30.230 57.000 1.600 2.020 0 -5.020 40.370 85.260 15.040 107.430 7.000 22.610 0 9.880 164.090 82.940 100.00 Table 4: European Countries Table 5: Former Communist Countries Variable Mean Standard Deviation Minimum Maximum Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy Urban Population 5.310 8.680 24.350 4.470 4.470 13.840 .820 -2.880 3.800 17.120 17.210 70.200 71.510 9.860 7.670 23.080 .380 222.240 71.200 74.250 27.540 7.440 5.900 149.780 .540 113.160 3.650 10.510 2.580 1.600 .600 0 -1.090 58.150 62.390 51.110 119.280 35.100 21.490 1382.000 2.070 595.090 78.080 97.510 Table 6: Latin American Countries Variable Mean Standard Deviation Minimum Maximum Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy Urban Population 31.59 24.040 14.880 24.330 3.730 6.140 5.290 14.820 2.900 138.780 28.010 33.900 72.700 10.890 4.690 61.670 .280 221.590 72.670 1,036,202 25.380 3.280 4.890 231.170 .580 139.200 2.820 26.43 19.580 3.900 .230 0 -2.280 57.640 65.420 12,197,100 152.660 19.800 18.580 1389.000 3.220 880.310 79.710 3,288,948 Table 7: North American Countries Variable Mean Standard Deviation Minimum Maximum Homicide Rates Temperature Male Youth Unemployment Price Index Infant Mortality Migrant Percentage Battle Deaths Income Difference Prison Population Life Expectancy Urban Population 2.570 11.160 13.830 1.920 5.160 2.740 .890 3.050 9.000 8.110 18.720 21.000 86.490 3.680 18.200 3.240 1.680 222.010 79.110 64.93 11.110 .590 3.540 27.460 1.960 162.620 1.640 17.040 67.640 2.800 10.710 0 -1.590 96.440 75.620 35.480 105.360 5.100 22.540 233.000 9.660 530.100 82.100 93.700