Understanding User Resistance Strategies in Persuasive Conversations (2020)

Abstract: Persuasive dialog systems have various usages, such as donation persuasion and physical exercise persuasion. Previous persuasive dialog systems research mostly focused on analyzing the persuader’s strategies and paid little attention to the persuadee (user). However, understanding and addressing users’ resistance strategies is an essential job of a persuasive dialog system. So, we adopt a preliminary framework on persuasion resistance in psychology and design a fine-grained resistance strategy annotation scheme. We annotate the PersuasionForGood dataset with the scheme. With the enriched annotations, we build a classifier to predict the resistance strategies. Furthermore, we analyze the relationships between persuasion strategies and persuasion resistance strategies. Our work lays the ground for developing a persuasive dialogue system that can understand and address user resistance strategy appropriately. The code and data will be released.

## introduction and related work persuasion plays a prominent role in human communication and has attracted more and more attentions in the nlp community @xcite @xcite @xcite . during persuasion, the persuader attempts to convince the persuadee to change his/her attitude, opinion or behavior. previous research on persuasive dialogs mainly study the persuader's strategies @xcite @xcite , which is helpful when the persuadee shows positive altitude towards the persuasion; but in other situations, the persuadees resists rather than embrace the persuasive attempt. for instance, in persuasionforgood @xcite , 166 out of 1,017 persuasive dialogs contains resistance strategy; although individuals resist persuasive attempts with different tactics, these resistant utterances all collapse into one dialog-act "negative-reactions-towards-persuasion" in the provided annotation scheme, which makes it harder for the persuasive system to respond accordingly. therefore, to achieve more efficient persuasion, we propose to study the resistance to persuasion in more details. persuasion resistance has been studied in social psychology, marketing and so on @xcite @xcite @xcite . @xcite showed that there exist individual differences in persuasion resistance dependent on their beliefs. further, one preliminary framework in psychology @xcite categorized the resistance behaviors into four main categories: avoidance, contesting, biased processing, and empowerment, as shown in figure 1 . in our work, we adopt this framework as a guidance, and design a more fine-grained annotation scheme with resistance strategies for persuasionforgood. two annotators label 447 persuadee resistant utterances in the dataset with six different resistance strategies. with these enriched labels, we build a classifier to predict the resistance strategies for further persuasive dialog system development. ## resistance strategy annotation scheme and analysis based on the framework in psychology @xcite , we design a fine-grained resistance strategy annotation scheme. as this persuasion task was complicated, different utterances in the same dialog turn may have different semantic meanings. we decide to annotate each utterance instead of the dialog turn, following @xcite . we identified six out of ten resistance strategies in the preliminary framework @xcite occured in the persuasionforgood (with the exception of contesting the source, reducing impact,optimism bias and social validation), and designed an annotation scheme accordingly. we hired two experts with persuasion theory training to annotate the persuasionforgood based on the scheme. they reached an inter-code reliability of kappa value of 0.806 for persuasionforgood. we shows the details of annotation scheme below together with some analyses. avoidance: avoidance refers to avoiding persuasion attempts. this is one of the most common and straightforward strategies to protect oneself from the impact of persuasive messages. self-assertion: people may resist persuasion by asserting their attitude. when they apply this strategy, they remind themselves that nothing can change their attitudes or behavior because they are confident about them. (e.g., persuader: any chance you would consider making a greater donation? (1) persuadee: this is all i can afford (2) persuadee: i can't afford much.(3) persuadee: unfortunately , i can't donate anything right now.(4) persuadee: 0.60 still sounds good to me.) all these four examples show that the persuadees assert themselves that they would not change their attitudes. when they apply self-assertion strategy, it is difficult for the persuader to persuade them. weighting-attributes: weighting attributes means more weight is attached to information that is consistent with one's attitudes and less weight is attached to inconsistent information. (e.g: (1)persuader: it's a fact that small donations by large numbers of people can have an impact. persuadee: how do we know the donation aren't simply buying another yacht for an executive? (2) persuader: it doesn't take much to save 30c a week. persuadee: that is true, but its hard to justify that 30c is going to make any difference.) both examples show that persuadee attach more weights to the side effects that may occur after they donate the money. contesting-content: contesting content means people reflect on the augments in the message and subsequently use counterarguments to refute it. it is a thought process that decreases agreement with a counter attitudinal message. (eg: (1) persuder: would you consider to donate? persuadee: i don't think so. (2) persuader: they are a good group. persuadee: that doesn't sound very good.) both examples show that persuadees refute the content from persuaders. attitude-bolstering: attitude bolstering is a process by which people generate thoughts that are supportive of their existing attitudes and behavior. (eg: persuadee: as they say, don't light yourself on fire to keep others warm.) this example shows that the persuadee uses the existing attitude to refuse the persuasion. persuasionforgood . it is mainly because this resistance strategy is relatively indirect compared with other resistance strategies. contesting-strategy: contesting strategy means people develop theories and beliefs about how persuasion agents try to influence them. (eg: persuader: so one last time how much exactly would you like to donate to the charity now? persuadee: pushiness does not make for a good salesperson.) in this example, the persuadee has developed their belief that the persuader tries to push for donation. then the persuadee contests the strategy that the persuader used. ## how resistance strategies influence donation rate there are altogether 166 out of 1,017 persuasive dialogs containing resistance strategy. with the enriched dataset, we first want to learn whether the resistance strategy can affect the persuasion result. so we calculate the donation rate for the dialogs with each resistance strategy. the dialogs with weighting attributes strategy have the highest donation rate. it is not surprising as the persuaders can use multiple persuasion strategies such as credibility appeal and logical appeal to eliminate the persuadees' concerns about certain attributes. for example, when persuadee said "how do we know the donation aren't simply buying another yacht for an executive? ", he has the concern for the usage of the donation. then the persuader said "a review of the tax exempt paperwork and financial statements can help you weed out good from bad." the persuader here uses credibility appeal strategy to address the persuadee's concern. so if the persuasive dialog system can classify different resistance strategies and apply different persuasion strategies to deal with certain resistance strategies, it can effectively increase the persuasiveness of the conversational agent. ## resistance strategy classification in order to build a persuasive dialog system with user resistance strategy awareness, we need to first understand the resistance persuasion patterns and differentiate various resistance persuasion strategies from each other. so we designed a classifier for the resistance persuasion strategies in persua-sionforgood dataset. ## conclusions and future work in this paper, we introduce a persuasion resistance strategy annotation scheme to assist persuasion dialog analyses and persusive dialog system building. we annotate the persuasionforgood dataset with the resistance strategy annotation scheme. we find that users who use resistance strategies are less likely to donate compared with users who don't show resistant attitudes. further, different resistance strategies have different impacts on the donation outcome. for example, it is more difficult for the persuader to handle with the self assertion strategy than the weighting attrbutes strategy. we also built a baseline classifier to classify different resistance persuasion strategies. results show that the classify can obtain relative high accuracy and f1 score. such classifier can assist persuasive dialog systems to identify different resistance strategies and choose corresponding persuasion strategies to deal with them. it is also helpful to build a user simulator when testing the persuasive dialog system. in conclusion, this study marks the first step to incorporate resistance strategy into a persuasive dialog system for better persuasion outcomes.