COW Militarized Interstate Disputes (v3.10)

Overview

Version 3.0 of the Militarized Interstate Dispute (MID) data collection compiled by the Correlates of War Project provides information about conflicts in which one or more states threaten, display, or use force against one or more other states between 1816 and 2001. Version 2.1 of the MID data set covered the 1816-1992 period. The data collection project that culminated in version 3.0 gathered new data on all MIDs that began between 1993 and 2001, along with those MIDs that began before 1993 but were still ongoing on December 31, 1992.

Version 3.10 (released on September 26, 2007) updates the data set with corrections made after an investigation of over 200 cases where errors or discrepancies had been reported to the COW project between 2003 and 2006. Version 3.10 includes a new version of the dyadic MID data set based on the corrected underlying MID data. Since all currently reported errors and discrepancies have been investigated and either corrected, or the original data judged correct, these official dyadic MID data should be considered to supersede other dyadic MID data sets.

“Militarized interstate disputes are united historical cases of conflict in which the threat, display or use of military force short of war by one member state is explicitly directed towards the government, official representatives, official forces, property, or territory of another state. Disputes are composed of incidents that range in intensity from threats to use force to actual combat short of war” (Jones et al. 1996: 163).


Citation

In any papers or publications that utilize this data set, users are asked to give the version number and cite the article of record for the data set, as follows:

Main Bibliography Entry: Ghosn, Faten, Glenn Palmer, and Stuart Bremer. 2004. "The MID3 Data Set, 1993–2001: Procedures, Coding Rules, and Description." Conflict Management and Peace Science 21:133-154.

Dyadic Data Set Bibliography Entry: Ghosn, Faten, and Scott Bennett. 2003. Codebook for the Dyadic Militarized Interstate Incident Data, Version 3.10. Online: http://correlatesofwar.org.

MID 2.1 codebook/citation. The codebook for the MID data version 3.0 builds on the documentation for the MID version 2.1 data set, which is available online: Daniel M. Jones, Stuart A. Bremer and J. David Singer (1996) ."Militarized Interstate Disputes, 1816-1992: Rationale, Coding Rules, and Empirical Patterns." Conflict Management and Peace Science, 15(2): 163:213.


Data Set

The files associated with the MID 3.0 data set can be obtained either individually, or in one ZIP file that contains several files. All data files are in .csv (comma-delimited) format. In this format, values are separated by commas, with string values (e.g. state names) in quotations. The first line of each data file is a header record containing the variable names.

MID-level data and documents:

MID_v3.0.codebook.pdf Main codebook for the MID 3.0 data set, describing file formats and listing variables contained in the MIDA and MIDB data files.
MID_v3.0.associated document.pdf Auxiliary information about the MID 3.0 data set, including discussion of new and changed variables, updates, and forthcoming MID-related data sets.
MIDA_3.10.csv Data on MIDs from 1816-2001, at the dispute level. Contains one record per militarized dispute.
MIDB_310.csv Data on MIDs from 1816-2001, at the participant level. Contains one record per militarized dispute participant.
MID_v3.0.narratives.pdf Narratives for MIDs containing a brief prose summary of key actors and actions.

Incident-level data and documents:

Codebook for MID Incident Data.pdf Main codebook for the MID 3.0 incident data sets, describing file formats and listing variables contained in the MIDI and MIDIP data files.
MIDI_3.10.csv Data on incidents within MIDs from 1993-2001 (along with disputes ongoing as of 12/31/1992), at the incident level. Contains one record per militarized incident.
MIDIP_3.10.csv Data on incidents within MIDs from 1993-2001 (along with disputes ongoing as of 12/31/1992), at the incident-participant level. Contains one record per participant in each incident.

Dyadic MID data and documentation:

Codebook for Dyadic MID Data v3.10.pdf Main codebook for the dyadic version of the MID 3.0 data set, describing coding procedures and the dyadic file format, and listing variables.
MIDDyadic_3.10.csv Data on dyadic MIDs from 1993-2001 (along with disputes ongoing as of 12/31/1992), at the dyad level. Contains one record per dyadic MID.

Documents discussing data changes:

Discussion - MID changes as of v3.10.pdf Document discussing changes made to MID data since v3.02.
Discussion - MIDs reviewed and unchanged as of v3.10.pdf Document discussing changes/questions examined, but where changes were not needed.

Click here to receive all files in a single zipped data set.


Source Data

Source data include the citations to the original materials used to code each dispute or incident.

All data files are in .csv (comma-delimited) format. In this format, values are separated by commas, with string values (e.g. state names) in quotations. The first line of each data file is a header record containing the variable names.

Source Data for MID 3.0: The source data used to code the MID 3.0 data set can be obtained either individually, or in one ZIP file that contains several files.

MID 3.0 SourceData Codebook.pdf Main codebook for the sources used in MID 3.0 data set, listing variables.
MID 3.0 Standard Source Abbreviations.pdf Main codebook for the sources used in MID 3.0 data set, listing variables.
MID3.0_Sources.csv
MID3.0_Sources.xls
Data on sources used to code incidents in MIDs from 1993-2001. The number of records per incident corresponds the number of sources used to code any given incident.

Source Data for MID 2.1: The source data used to code the MID 2.1 data set can be obtained either individually, or in one ZIP file that contains several files.

MID 2.1 SourceData Codebook.pdf Main codebook for the sources used in MID 2.1 data set, providing historical overview of the project and listing variables.
MID2.1_SpecificSources.csv Data on sources used to code incidents in MIDs prior to 1993. The number of records per MID corresponds the number of sources used to code any given dispute.
MID2.1_GeneralSources.csv Data on sources used to code MIDs prior to 1993. The file contains the full names for sources which are abbreviated in the source data file, and sources contained in the COW MID bibliography that do not correspond to specific MID numbers.

Relationship between MIDs and Wars

Version 3.0 of the Correlates of War Inter-State War data set is matched to Version 3.10 of the Militarized Interstate Dispute (MID) data set. Each interstate war between 1816 -1997 has its corresponding dispute. This report is available for download here.


Pre-1993 MID Data

Dyadic MID data is only available from the Correlates of War project from 1993-2001, because incident data (showing direct dyadic interaction) has only been systematically coded since 1993.  For the pre-1993 period, either assumptions must be made in coding dyadic interaction (critically, that all states on opposite sides interacted), or additional research must be performed to identify actual interactions.  In addition, coding to a dyadic form must carefully check dates of state involvement to verify that states were opponents at the same time.

MID v.2.1 (running from 1816-1992):

MID 2.1.zip The .zip file contains main codebook in .txt format and three data files in .txt format.

MID v.2.1EE provides information on a subset of escalatory incidents in 1816-1992:

MID 2.1 EE.zip The .zip file contains main codebook in .pdf format and the data file in .csv format.

There are two other versions of the dyadic MID data available for the pre-1992 period which tackle these issues in different ways. Extensive documentation on procedures are available in the documentation at both sites:

Scott Bennett’s EUGene software (v3.2, 2008):

http://www.eugenesoftware.org/ EUGene generates dyadic MID data from 1816-2001 using the most recent MID data (3.1).  It allows data to be formatted with several units of analysis, including dyadic-dispute, dyadic-dispute-year, and dyad-year formats, each directed or nondirected.  EUGene constructs dyads of states involved on opposite sides at the same time, but does not add new historical research. 

Zeev Maoz’s dyadic MID data (v2.0, 2005):

http://psfaculty.ucdavis.edu/zmaoz/dyadmid.html/ The data set incorporates historical research on individual dyads rather than just taking all possible dyadic combinations, but does not use the most recent MID data and contains some unilateral coding changes to the data. 

Updates

  1. Data Updates for MID v.3.10:

    On September 26, 2007, the MID data were updated to version 3.10. Updating for version 3.10 focused on the following issues:

    • Since the release of v3.02, the COW project has investigated error reports, questions, and reports of discrepancies on nearly 150 particular MIDs submitted by numerous scholars, including Zeev Maoz, Patrick Regan, Russell Leng, Ashley Leeds, Mark Souva, and others. Each report has been investigated, and v3.10 has made changes/corrections to 74 different MIDs (the remaining MIDs did not require changes; error reports typically resulted from a misinterpretation of coding rules). There have been changes to a total of 100 MIDs since the release of MID 3.0. You may review a detailed cumulative list of these questions and changes that resulted here. A detailed listing of questions examined where it was determined that no changes in the data were required is here.
    • Dyadic MIDs: The COW dyadic MID set (1993-2001) breaks down overall MIDs, some of which have many participants, into actual disputing pairs of states. Each dyadic MID has exactly two states involved on opposite sides; each was directly involved in militarized incidents against the other. The data set omits dyads where the two states were on opposite sides of a multi-party dispute, but never took action towards one another. While there are approximately 300 MIDs from 1993-2001, there are over 500 dyadic MIDs during this period. Version 3.10 corrects errors in the dyadic data set. These errors most often resulted from errors in the underlying (non-dyadic) MID data sets that carried over to the dyadic MID set. Other corrections and additions to the data include the following. 1) Dyadic MIDs and the related dates were not being correctly computed for states exiting and reentering a MID; in such circumstances, a new dyadic MID is now correctly coded. 2) The data now include a "dyadic MID number" as well as the base MID number; this number separates each pair of disputing states, and separates incidents of repeated involvement. 3) Hostility levels were not always reported correctly in the dyadic MID data set in the case of war. It is sometimes the case that a MID has a hostility level of "5" (war) even though no single incident reaches hostility level 5. This is because multiple instances of a use of force (hostility level "4") can accumulate to a level of war. These cases were not always picked up in the MID 3.02 data; they have been corrected with hostility levels in such cases being taken from the MIDB data set rather than the MID IP (incident) data. 4) The end dates of dyadic MID were in some cases not being correctly computed; the end date of the last incident between two states in a MID is not automatically the correct end date of the dyadic MID, as MIDs can end days or weeks after the end of the last incident. These dates have been corrected.
  2. Incident Level Data and Dyadic Data Updates for MID v.3.02

    On October 10, 2003, we replaced version 3.01 of the MID data with version 3.02. The data sets for version 3.02 include the following:

    • Incident and Incident Participant level data files: Incidents are the building blocks of MIDs, and represent individual militarized actions incidents (specific threats, displays, or uses of force) that comprise the disputes. MIDs may consist of one or many specific incidents. The MID 3.0 incident data collection reports information on each of the militarized incidents occurring with MIDs (incidents may be either escalatory or de-escalatory). MID-I contains the essential elements of each militarized interstate incident from 1993-/2001 (incidents that belonged to disputes that began in 1992 and continued into 1993 were also collected). MID-IP describes the participants in each of those incidents.
    • Dyadic MIDs: The COW dyadic MID set from 1993-2001 breaks down overall MIDs, some of which have many participants, into actual disputing pairs of states. Each dyadic MID has exactly two states involved on opposite sides; each was directly involved in militarized incidents against the other. The data set omits dyads where the two states were on opposite sides of a multi-party dispute, but never took action towards one another. While there are approximately 300 MIDs from 1993-2001, there are over 500 dyadic MIDs during this period.
    • Minor Corrections: We have made a few minor changes to data on the MIDs that were newly collected between 1992 and 2003. You may review a summary of these changes here.
    • Revisiting older MIDs: In response to various comments and questions about MID codings from the v2.1 data set, we have revisited a number of pre-1992 MIDs and made 25 corrections/changes/additions. You may review a detailed list of these questions and resulting changes here, and a detailed listing of questions considered which did not necessitate changes here.

    Because the new data version include numerous documentation files, we have released all documentation files in .pdf format only. Users wishing to cut and paste from these documents can still do so using the "t" keystroke command within Adobe.

    A typo was discovered in the MIDA_3.02.csv data file on October 14, 2003 (the MID number for MID 21 was mistakenly listed as a 20, so it appeared that MID 20 was listed twice and MID 21 not at all). The MID number for MID 21 has been corrected in MIDA_3.021.csv, which replaces MIDA_3.02.csv. No other data files were affected by the typo.

  3. MIDB Dataset Updates (v.3.01)

    On March 23, 2003, we replaced version 3.00 of the MID data with version 3.01. The data in the MIDA file (main MID listing) is identical from version 3.00 to version 3.01. However, we found an erroneous case in version 3.00 of the MIDB file, and have deleted this case in version 3.01 (it should not have been in there in the first place). The case was MIDB data set dispute number 4241. This is the only change from version 3.00 to version 3.01.

    With this release, we have also made available text file versions of the documentation as .rtf files, along with .pdf files.


Development Materials

Version 3.0 was developed through a 3-year multi-university initiative supported by the National Science Foundation. The project would not have been completed without the participation of co-PIs Scott Bennett, Stuart Bremer, Paul Diehl, Dan Geller, Doug Gibler, Paul Hensel, Chuck Gochman, Zeev Maoz, Glenn Palmer, Brian Pollins, Jim Ray, Pat Regan, and Ric Stoll. We have preserved the key documents used during the project's data creation phase. To access these documents, or to review the participants in the project, select among the following links:


Questions and Feedback

The militarized dispute data are hosted by Glenn Palmer, Pennsylvania State University, under the COW Data Set Hosting Program. In case of questions or concerns concerning the data or coding rules, he may be contacted by email at gpalmer@psu.edu.