Replication materials for the paper "Comparing automated content analysis methods to distinguish issue communication by political parties on Twitter", authored by Stiene Praet, Peter Van Aelst, Walter Daelemans, Tim Kreutz, Jeroen Peeters, Stefaan Walgrave, and David Martens. Available at SSRN: http://ssrn.com/abstract=3782027.

Abstract: Party competition in Western Europe is increasingly focused on “issue competition”, which is the selective emphasis on issues by parties. The aim of this paper is to contribute methodologically to the increasing number of studies that deal with different aspects of parties’ issue competition and communication. We systematically compare the value and shortcomings of three exploratory text representation approaches to study the issue communication of parties on Twitter. More specifically, we analyze which issues separate the online communication of one party from that of the other parties and how consistent party communication is. Our analysis was performed on two years of Twitter data from six Belgian political parties, comprising of over 56,000 political tweets. The results indicate that our exploratory approach is useful to study how political parties profile themselves on Twitter and which strategies are at play. Secondly, our method allows to analyze communication of individual politicians which contributes to classical literature on party unity and party discipline. A comparison of our three methods shows a clear trade-off between interpretability and discriminative power, where a combination of all three simultaneously provides the best insights.

Fig. 1: Schematic representation of the methods we propose in this paper

• flemish_parliamentarians List of Flemish parliamentarians (2017) from which tweets were collected
• 20140718_dutchdictionary_v2.lcd Dutch CAP dictionary, compiled by Sevenans et al. (2014).
• tweet_ids Tweet IDs from the political tweets used in this study. In line with the Twitter policy we only store tweet IDs, but the tweets can be hydrated using readily available tools such as Hydrator.
• json_to_excel.py Load json file with hydrated tweets line by line and store tweet_id, screen_name, text, created_at, hashtags, mentions, and retweeted_user in excel file. You can merge this file with tweet_ids (to add political party per tweet) and use for analysis.

• 01-preprocessing.py Preprocessing of the text of the tweets (see section 3.2 in paper). This includes: (1) replace named entities, mentions, numbers, and urls (2) remove punctuation and stopwords (Dutch, French, and English) (3) normalize (reduce to word lemma)
• 02-expert_issues.py Discriminative power and the most discriminative issues per political party when applying the models based on expert issues (Table 6 and Table 7 of the paper)
• 03-BoW.py Discriminative power and the most discriminative words per political party when applying the models based on Bag of Words (Table 7 and Table C1 of the paper)
• 04-topic_models.py Discriminative power and the most discriminative topics per political party when applying the models based on topic modeling (Table 7 and Table C2 of the paper)