Mongo DB Atlas and R
10 Sep 2018At One Earth Future Research our mission is to utilize rigorous research methodologies in an effort to provide empirical assessment of the root-causes of political violence and the efficacy of governance and development programs. I will be starting a semi-weekly blog that highlights some of our work in both the conflict trends and forecasting tracks. Our collective goal is to utilize data to explore the mechanisms of conflict and the long-term shifts in conflict related phenomena (conflict trends) and to understand and predict short term outcomes in conflict and political violence (forecasting). Our organization utilizes field work and in-depth interviews alongside state of the art technical approaches found in inferential statistics and machine learning/artificial intelligence.
Setup and Data
As we went about the process of creating a centralized data repository for all organizational data, we stumbled upon MongoDB’s Atlas platform. Atlas utilizes the MongoDB document system and is accessible from the cloud (AWS, Google Cloud, or Azure). This blog provides some demonstration code for utilizing Atlas in the R programming environment with our soon-to-be released election violence data.
Our data
We have a data set of all major national elections from 1975 to 2018 that is based on original data gathering and the NELDA dataset put together by Hyde and Marinov1 and our own REIGN dataset2. For this demonstration, we will simply use the name ev_df for our new election violence data for the time being.
Let’s quickly inspect our data before moving it into Atlas.
summary(ev_df)
## year country dates
## Min. :1975 Ecuador : 35 10/25/2015: 8
## 1st Qu.:1990 United States of America: 33 10/24/1999: 6
## Median :2000 Iran : 32 10/23/2011: 5
## Mean :1999 France : 31 10/31/1999: 5
## 3rd Qu.:2009 Egypt : 29 11/28/2010: 5
## Max. :2018 Guatemala : 29 11/28/2011: 5
## (Other) :2074 (Other) :2229
## elecViolence l.elecViolence anticipation regimetenure
## vio : 617 0:1645 Min. :0.0000 Min. : 1.00
## peace:1623 1: 618 1st Qu.:0.0000 1st Qu.: 27.00
## NA's : 23 Median :1.0000 Median : 56.00
## Mean :0.6879 Mean : 83.39
## 3rd Qu.:1.0000 3rd Qu.:109.00
## Max. :1.0000 Max. :589.00
##
## lastelection pcgdp growth logIMR
## Min. :0.000 Min. : 0.0 Min. :0.09887 Min. :0.6419
## 1st Qu.:0.000 1st Qu.: 709.6 1st Qu.:0.99141 1st Qu.:2.3842
## Median :0.000 Median : 2143.7 Median :1.05674 Median :3.3464
## Mean :1.068 Mean : 7269.8 Mean :1.06457 Mean :3.2260
## 3rd Qu.:2.441 3rd Qu.: 7933.4 3rd Qu.:1.12739 3rd Qu.:4.1558
## Max. :8.098 Max. :102573.7 Max. :4.09959 Max. :5.1728
##
## lnpop2 logpredict SPI lexconst
## Min. : 31.48 Min. :0.0000221 Min. :-2.561111 Min. :1.000
## 1st Qu.: 69.81 1st Qu.:0.0006450 1st Qu.:-0.428677 1st Qu.:3.000
## Median : 84.67 Median :0.0015977 Median : 0.023829 Median :5.000
## Mean : 88.17 Mean :0.0038759 Mean :-0.001438 Mean :4.803
## 3rd Qu.:105.59 3rd Qu.:0.0037408 3rd Qu.: 0.428446 3rd Qu.:7.000
## Max. :197.67 Max. :0.1414839 Max. : 2.682971 Max. :7.000
##
## lpolity2 lpolcomp
## Min. :-10.000 Min. : 1.000
## 1st Qu.: -4.000 1st Qu.: 3.000
## Median : 6.000 Median : 7.000
## Mean : 3.186 Mean : 6.603
## 3rd Qu.: 9.000 3rd Qu.: 9.000
## Max. : 10.000 Max. :10.000
##
The data contains 17 variables and captures 2263 unique elections across the 1975 - 2018 time period.3
Setting up connection and uploading data to cluster
As of right now, we have no data housed on our Atlas cluster called OEFdata. To send data to our Atlas cluster, we can use the mongolite package.
library(mongolite)
#find cluster url with username and password replaced with SCRAM credentials
url_path = 'mongodb+srv://<username here>:<password here>!@<cluster url>/admin'
#make connection object that specifies new database and collection (dataset)
mongo1 <- mongo(collection = "EV_Forecast Data (1975 - 2018)", db = "OEFR",
url = url_path,
verbose = TRUE)
#show commands for connection
mongo1
## <Mongo collection> 'EV_Forecast Data (1975 - 2018)'
## $aggregate(pipeline = "{}", options = "{\"allowDiskUse\":true}", handler = NULL, pagesize = 1000, iterate = FALSE)
## $count(query = "{}")
## $disconnect(gc = TRUE)
## $distinct(key, query = "{}")
## $drop()
## $export(con = stdout(), bson = FALSE, query = "{}", fields = "{}", sort = "{\"_id\":1}")
## $find(query = "{}", fields = "{\"_id\":0}", sort = "{}", skip = 0, limit = 0, handler = NULL, pagesize = 1000)
## $import(con, bson = FALSE)
## $index(add = NULL, remove = NULL)
## $info()
## $insert(data, pagesize = 1000, stop_on_error = TRUE, ...)
## $iterate(query = "{}", fields = "{\"_id\":0}", sort = "{}", skip = 0, limit = 0)
## $mapreduce(map, reduce, query = "{}", sort = "{}", limit = 0, out = NULL, scope = NULL)
## $remove(query, just_one = FALSE)
## $rename(name, db = NULL)
## $replace(query, update = "{}", upsert = FALSE)
## $run(command = "{\"ping\": 1}", simplify = TRUE)
## $update(query, update = "{\"$set\":{}}", filters = NULL, upsert = FALSE, multiple = FALSE)
Use the $insert command to store the data in your Atlas collection.
mongo1$drop()
mongo1$insert(ev_df)
##
Processed 1000 rows...
Processed 2000 rows...
Complete! Processed total of 2263 rows.
## List of 5
## $ nInserted : num 2263
## $ nMatched : num 0
## $ nRemoved : num 0
## $ nUpserted : num 0
## $ writeErrors: list()
Analysis commands and pulling data into R.
Now our original R dataframe is hosted in our Atlas cluster in the MongoDB document format and we can start to analyze and manipulate data that is already stored in our cluster.
#count number of documents (rows)
mongo1$count()
## [1] 2263
#import data frame back into R
ev_df2 <- mongo1$find()
##
Found 1000 records...
Found 2000 records...
Found 2263 records...
Imported 2263 records. Simplifying into dataframe...
str(ev_df2)
## 'data.frame': 2263 obs. of 17 variables:
## $ year : int 1978 1982 1987 1991 1991 1992 1992 1996 1996 1997 ...
## $ country : chr "Albania" "Albania" "Albania" "Albania" ...
## $ dates : chr "11/12/1978" "11/14/1982" "2/1/1987" "3/31/1991" ...
## $ elecViolence : chr "peace" "peace" "peace" "vio" ...
## $ l_elecViolence: chr "0" "0" "0" "0" ...
## $ anticipation : num 1 1 1 1 1 1 1 1 1 1 ...
## $ regimetenure : num 409 457 23 72 73 84 84 50 51 63 ...
## $ lastelection : num 0 0 0 0 0 0 0 0 0 0 ...
## $ pcgdp : num 628 798 807 410 410 ...
## $ growth : num 1.061 1.008 0.973 0.611 0.611 ...
## $ logIMR : num 4.29 4.03 3.71 3.52 3.52 ...
## $ lnpop2 : num 61.6 62.9 64.7 65.6 65.6 ...
## $ logpredict : num 0.00273 0.00222 0.00236 0.00302 0.00329 ...
## $ SPI : num 0.00931 0.25154 -0.39167 -1.55961 -1.2355 ...
## $ lexconst : int 1 1 1 3 3 3 3 5 5 5 ...
## $ lpolity2 : int -9 -9 -9 1 1 1 1 5 5 0 ...
## $ lpolcomp : int 1 1 1 6 6 6 6 6 6 6 ...
The find function can also be used for making conditional queries from our Atlas cluster, and is especially useful for big data that may not play well with your local R instance. Lets demonstrate some ways to query/subset from our election violence data.
#use the query argument to subset by rows
#lets get all observations that experienced election violence
ev_df2 <- mongo1$find(query = '{"elecViolence":"vio"}')
##
Found 617 records...
Imported 617 records. Simplifying into dataframe...
#inspect our subsetted data frame
nrow(ev_df2)
## [1] 617
#use the fields argument to subset by columns
#lets query the above data, but only getting country and date information
ev_df2 <- mongo1$find(query = '{"elecViolence":"vio"}',
fields = '{"country": true, "dates": true}')
##
Found 617 records...
Imported 617 records. Simplifying into dataframe...
#inspect data frame variables
summary(ev_df2)
## _id country dates
## Length:617 Length:617 Length:617
## Class :character Class :character Class :character
## Mode :character Mode :character Mode :character
Now we can create a new cluster collection to host our subsetted data
#now lets upload our new subset into it's own Atlas collection
#make new connection within the OEFR database
mongo2 <- mongo(collection = "Election Violence Events (Country, Dates)", db = "OEFR",
url = url_path,
verbose = TRUE)
mongo2$insert(ev_df2)
##
Complete! Processed total of 617 rows.
## List of 5
## $ nInserted : num 617
## $ nMatched : num 0
## $ nRemoved : num 0
## $ nUpserted : num 0
## $ writeErrors: list()
If you need to delete a a collection (data frame) from your Atlas cluster, you can use the following.
#drop and delete collection tab in Atlas
mongo2$drop()
#drop data frame, but keep collection tab in Atlas
mongo2$drop{'{}'}
Finally, we can query aggregate statistics from our Atlas cluster using MongoDB’s pipeline syntax. Aggregating at the group level is useful for getting more managable data sets when dealing with big data. Lets demonstrate this capability using our election violence data!
#Lets get the count of country elections and the average infant mortality rate and SPI (precipitation) by country
agg_stats <- mongo1$aggregate('[{"$group":{"_id":"$country", "election events": {"$sum":1},
"average IMF":{"$avg":"$logIMR"}, "average SPI":{"$avg":"$SPI"}}}]'
)
##
Found 152 records...
Imported 152 records. Simplifying into dataframe...
#show first 25 rows of country aggregated data
head(agg_stats, n = 25)
## _id election events average IMF average SPI
## 1 Zimbabwe 19 4.043437 0.33245826
## 2 Venezuela 21 3.006033 0.20093259
## 3 Uzbekistan 12 3.817488 -0.02127261
## 4 United States of America 33 2.115447 -0.03168326
## 5 United Kingdom 10 1.810915 -0.07704831
## 6 Ukraine 19 2.579029 0.21402413
## 7 Thailand 22 3.090824 0.24227424
## 8 Sweden 13 1.465030 -0.17207021
## 9 Swaziland 6 4.205235 -0.12403276
## 10 Surinam 2 3.020008 -0.92425866
## 11 Sudan 12 4.218346 -0.11023233
## 12 Spain 12 1.880806 -0.24571050
## 13 South Africa 9 4.058460 0.04487938
## 14 Somalia 4 4.662905 -0.62259620
## 15 Solomon Islands 2 3.233632 0.18578571
## 16 Syria 17 3.159167 -0.26130308
## 17 Slovakia 13 2.104528 0.06276020
## 18 Singapore 13 1.447405 0.43001852
## 19 Serbia (Yugoslavia) 3 3.039749 -0.64691414
## 20 Senegal 18 4.168331 -0.18662808
## 21 Rwanda 13 4.243818 0.25100911
## 22 Russia 14 2.686567 -0.01138183
## 23 Romania 23 2.997278 -0.22977333
## 24 Portugal 22 2.052871 -0.24904753
## 25 Poland 22 2.230286 0.08542938
Susan D. Hyde and Nikolay Marinov, 2012, Which Elections Can Be Lost?, Political Analysis, 20(2), 191-201.↩
Bell, Curtis. 2016. The Rulers, Elections, and Irregular Governance Dataset (REIGN). Broomfield, CO: OEF Research. Available at oefresearch.org↩
Information about our election violence data and collection/analysis methodology will be explored in future blogs.↩