Please provide answers to question 7, 8 and 9 only. The other questions posted are only in reference to help answer the following questions. Thank you.

Leader Assassination as a Natural Experiment One longstanding debate in the study of international relations concerns the question of whether individual political leaders can make a difference. Some argue that leaders with different ideologies and personalities can significantly affect the course of a nation. Others argue that political leaders are severely constrained by historical and institutional forces. Did individuals like Hitler, Mao, Roosevelt, and Churchill make a big difference? The difficulty of empirically testing these arguments stems from the fact that changes in leadership are not generally random. In this exercise, we consider a natural experiment in which the success or failure of assassination attempts may be essentially random, at least with respect to the outcomes in which we are interested. This exercise is based on: Jones, Benjamin F, and Benjamin A Olken. 2009. "Hit or Miss? The Effect of Assassinations on Institutions and War." American Economic Journal: Macroeconomics 1(2): 55-87. Each observation of the CSV dataset leaders.csv contains information about an assassination attempt. The variables are: The polity variables represent "Polity scores" from the Polity Project. The Polity Project assigns an annual Polity score to all countries in the world from 1800 to the present as a measure of each country's political institutions. The Polity score is a 21-point scale ranging from -10 (hereditary monarchy) to 10 (consolidated democracy). The result variable is a 10 category text variable describing the result of each assassination attempt: dies between a day and a week; dies between a week and a month; dies within a day after the attack; dies, timing unknown; hospitalization but no permanent disability; not wounded; plot stopped; survives but wounded severely; survives, whether wounded unknown; wounded lightly. Question 1 (all questions 10 pts each) How many assassination attempts are recorded in the data? What is the average age of a leader across all assassination attempts in the data? What is the first year in which an assassination attempt is recorded in the data? Answer 1 \# insert code here Insert written answer here. Many researchers collapse the Polity scores to create binary autocracy/democracy indicators, because it is not clear that the Polity scores can or should be interpreted as measuring linear variation from autocracy to democracy. We will do that, too. First, create a new binary pre-assassination democracy variable in the dataset that is equal to 1 if politybefore is greater than 0, and equal to 0 otherwise (hint: the ifelse command will be helpful here). Next, create a new binary post-assassination democracy variable in the dataset that is equal to 1 if polityafter is greater than 0 , and equal to 0 otherwise. What proportion of countries in which assassination attempts occurred were democracies in the three years prior to the attempt, as measured by your new democracy variable? What proportion of countries in which assassination attempts occurred were democracies in the three years after the attempt, as measured by your new democracy variable? In order to investigate whether successful assassinations affect countries' political institutions and likelihood of being involved in a war, we need to assess whether there are any confounders that might affect both assassination success and changes in post-assassination outcomes. Identify three variables in the dataset that might plausibly be confounders as described above. For each variable, explain why we might think that the variable might affect both assassination success and changes in post-assassination outcomes. Answer 3 Insert written answer here. Question 4 We can explore the potential for confounding using our data. Using your newly created pre-assassination democracy variable, what proportion of countries were democracies prior to unsuccessful assassination attempts? What proportion of countries were democracies prior to successful assassination attempts? (Hint: you may want to use either the subset() command or brackets [] to select subsets of observations.) What does this tell you about whether pre-assassination political institutions are likely to be a confounder in an analysis of the effect of assassination success on post-assassination outcomes? Likewise, what was the mean leader age prior to unsuccessful assassination attempts? What was the mean leader age prior to successful assassination attempts? What does this tell you about whether leader age is likely to be a confounder in an analysis of the effect of assassination success on post-assassination outcomes? Next, create a new binary pre-assassination war variable in the data frame that is equal to 1 if a country is in either civil or international war during the 3 years prior to an assassination attempt, and equal to 0 otherwise. Also, create a new binary post-assassination war variable in the data frame that is equal to 1 if a country is in either civil or international war during the 3 years after an assassination attempt, and equal to 0 otherwise. Then, repeat the analysis in Question 4 to assess whether a country's pre-assassination involvement in civil or international war is likely to be a confounder in an analysis of the effect of assassination success on post-assassination outcomes. What do you learn? Answer 5 \#\# insert code here Insert written answer here. Question 6 Does successful leader assassination affect a country's political institutions? To answer this question, first create a variable that represents the absolute value of the difference between a country's pre-assassination democracy variable and its post-assassination democracy variable (using the democracy varaibles you created). What is the proportion of countries that experience a change in political institutions after a successful assassination attempt? Among the set of countries that were democracies prior to assassination attempts, what is the proportion that experience a transition to autocracy after a successful assassination attempt? Among the set of countries that were autocracies prior to assassination attempts, what is the proportion that experience a transition to democracy after a successful assassination attempt? What does this analysis tell you about the effect of successful leader assassination on a country's political institutions? Question 7 Now incorporate change in political institutions after unsuccessful assassination attempts into your analysis. What is the proportion of countries that experience a change in political institutions after an unsuccessful assassination attempt? Among the set of countries that were democracies prior to assassination attempts, what is the proportion that experience a transition to autocracy after an unsuccessful assassination attempt? Among the set of countries that were autocracies prior to assassination attempts, what is the proportion that experience a transition to democracy after an unsuccessful assassination attempt? How can you use this information to improve your analysis in Question 6? Answer 7 \# insert code here Insert written answer here. Question 8 For each of these three outcomes (change in political institutions among all countries, change in political institutions among pre-assassination democracies, and change in political institutions among pre-assassination autocracies), find the differences-in-differences estimates across successful and unsuccessful assassination attempts in both percentage point and percent terms. To find percentage point differences-in-differences estimates, subtract the proportion of countries that changed political institutions after unsuccessful assassination attempts from the proportion of countries that changed political institutions after successful assassination attempts, and multiply by 100 . To find percent differencesin-differences estimates, divide each percentage point difference by the percent of countries that changed political institutions after unsuccessful assassination attempts. What are the difference-in-differences results for all countries experiencing assassination attempts? What are the difference-in-differences results for democracies that experience assassination attempts? What are the difference-in-differences results for autocracies that experience assassination attempts? Make sure to interpret each result in the correct units of measurement. What do you learn from this analysis? Answer 8 \#\# insert code here Insert written answer here. Question 9 Following the steps above, construct differences-in-differences analyses of the effect of successful assassinations on a country's involvement in civil or international war (using the war variable you created, for both percentage point and percent differences-in-differences). What are the difference-in-differences results for all countries experiencing assassination attempts? What are the difference-in-differences results for countries that were not involved in a war prior to the assassination attempt? What are the difference-in-differences results for countries that were involved in a war prior to the assassination attempt? What do you learn from this analysis about the effect of successful assassinations on a country's involvement in civil or international war