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Can Partisan News Shift Political Preference and Voting Behavior? An Experimental Evidence from Taiwan’s General Election 2016
Last registered on October 28, 2019


Trial Information
General Information
Can Partisan News Shift Political Preference and Voting Behavior? An Experimental Evidence from Taiwan’s General Election 2016
Initial registration date
October 26, 2019
Last updated
October 28, 2019 11:18 AM EDT
Primary Investigator
Department of Economics, National Taiwan University
Other Primary Investigator(s)
Additional Trial Information
Start date
End date
Secondary IDs
We conducted a field experiment to investigate the effects of partisan news on the 2016 Taiwan Presidential and Legislative Elections. Subjects are randomly divided into four groups: KMT the ruling party, DPP, the opposition party, the new third-party and control, and provided them with distinct partisan news articles. We find that the pro DPP news articles have significantly increased the support for the DPP candidate Tsai by reinforcing the existing preferences. Pro third-parties articles have changed subjects' voting intentions to support the new party GSD. We also find that the estimated baseline and reinforcement treatment effects are driven by undecided subjects.
External Link(s)
Registration Citation
Lin, Ming-Jen. 2019. "Can Partisan News Shift Political Preference and Voting Behavior? An Experimental Evidence from Taiwan’s General Election 2016." AEA RCT Registry. October 28. https://doi.org/10.1257/rct.4934-1.0.
Experimental Details
We randomly assigned partisan news articles to our subjects during one month before the 201 General Election in Taiwan. During the period of intervention, we asked subjects to complete reading comprehension to the news articles to ensure the readership. Also, we asked subjects their political preferences and voting intentions toward the 2016 election.
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
The voting decisions subjects reported in 2016 General Election
Primary Outcomes (explanation)
If the subjects didn't turn out to vote, we instead asked the same hypothetical questions applied during the intervention (e.g. If you were to turn out to vote, which party/candidate would you vote for?).
Secondary Outcomes
Secondary Outcomes (end points)
1. The voters' preference to parties or candidates.
2. The voters' media consumption behavior.
Secondary Outcomes (explanation)
We surveyed the voters' preference with several 10-scaled questions on each candidate or party, and we asked how often subjects consume news from specific media sources.
Experimental Design
Experimental Design
The subjects are divided into four treatment groups by the article they received: articles favoring KMT (the ruling party), favoring DPP (the opposing party), favoring NPP and GSD (new emerging party) and control group (receiving news articles unrelated to politics, like sport or entertainment).
Experimental Design Details
Randomization Method
Randomization was done in office by computer with STATA, seed id 20160116.
Randomization Unit
We assigned treatments individually.
By the initial survey, we divided subjects into two blocks: people initially favoring KMT or people initially favoring DPP. Within each block, we randomize the treatment assignments evenly.
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
200 subjects.
Sample size: planned number of observations
200 subjects.
Sample size (or number of clusters) by treatment arms
50 in KMT treatment group, 50 in DPP, 50 in THIRD PARTIES (NPP/GSD), 50 in Control
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Intervention Completion Date
January 15, 2016, 12:00 AM +00:00
Is data collection complete?
Data Collection Completion Date
February 02, 2016, 12:00 AM +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
190 subjects
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
190 subjects
Final Sample Size (or Number of Clusters) by Treatment Arms
50 Control, 48 KMT, 49 DPP, 43 THIRD PARTIES
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)