Free-form Messages Research Articles

An Experimental Study of Message Strategies for Mobile Alerts and Warnings

Dr. Dennis Mileti devoted his career to the study of public warnings disseminated through mass media, word of mouth, and, later, mobile technologies. To date, research on mobile public warnings has focused on standardized elements of messages (e.g., the common alerting protocol). During this same period, however, a variety of private, public, and governmental organizations have adopted mobile alert technologies to disseminate a diverse variety of free-form (nonstandardized) messages. We investigated how the evidence-based guidance developed for mobile public warnings applies to this broader class of free-form mobile alerts and warnings (FMAWs). This study reports an experimental comparison of US residents’ (N=299) reactions to notional free-form mobile messages about a safety risk. Experimental conditions compared messages that included safety instructions, ways to seek additional information, expressions of empathy, and emphasizing choice (“choice forward”). Results indicated that message efficacy was greater for FMAWs that gave safety instructions rather than just notifications. Choice-forward FMAWs produced both message efficacy and safety efficacy, or confidence that the person could make a good safety decision for the situation. Application: When the location, timing, and severity of an emergent risk are ambiguous, or when for public safety organizations, they have not yet reached a threshold appropriate for wireless emergency alert messages, a free-form message disseminated through mobile technologies or social media could use choice-forward language and links to more detailed information about possible self-protective action to facilitate just-in-time pre-event education and preparedness.

Demanding or Deferring? The Economic Value of Communication with Attitude

This paper investigates why natural language communication is systematically found to promote coordination better than intention signaling. We hypothesize that, when communicating with natural language, people both use and respond to intentions and attitudes, where attitude indicates the strength of desire to have their intentions followed. We test our hypothesis using controlled laboratory experiments. We find (i) free-form messages do include both intentions and attitudes; (ii) people respond both to intentions and attitudes when making decisions; and (iii) the use of attitude significantly improves coordination.

Demanding or deferring? An experimental analysis of the economic value of communication with attitude

Research has shown that natural language communication is more effective than intention-signaling in promoting coordination. Our paper studies the reasons behind this finding. We hypothesize that, when communicating with natural language, people use and respond to both intentions and attitudes, with attitude indicating the strength of a message sender's desire to have her message followed. We test our hypothesis using controlled laboratory experiments. We find that: (i) free-form messages include both signaled intentions and attitudes; (ii) people respond to both intentions and attitudes when making decisions; and (iii) the use of attitude in natural language messages significantly improves coordination.

An Experimental Study on the Effects of Communication, Credibility, and Clustering in Network Games

The effectiveness of social interaction depends strongly on an ability to coordinate actions efficiently. In large networks, such coordination may be very difficult to achieve and may depend on the communication technology and the network structure. We examine how pre-play communication and clustering within networks affect coordination in a challenging experimental game on eight-person networks. Free-form chat is enormously effective in achieving the non-equilibrium efficient outcome in our game, but restricted communication (where subjects can only indicate their intended action) is almost entirely ineffective. We can rationalize this result with a novel model about the credibility of cheap-talk messages. This credibility is much larger with free-form message communication than with restricted communication. We are the first to model this credibility and show, both theoretically and experimentally, an interaction effect of network structure and communication technologies. We also provide a model of message diffusion, which indeed predicts that diffusion will be more rapid without clustering and is consistent with our data.

An Experimental Study on the Effects of Communication, Credibility, and Clustering in Network Games

The effectiveness of social interaction depends strongly on an ability to coordinate actions efficiently. In large networks, such coordination may be very difficult to achieve and may depend on the communication technology and the network structure. We examine how pre-play communication and clustering within networks affect coordination in a challenging experimental game on eight-person networks. Free-form chat is enormously effective in achieving the non-equilibrium efficient outcome in our game, but restricted communication (where subjects can only indicate their intended action) is almost entirely ineffective. We can rationalize this result with a novel model about the credibility of cheap-talk messages. This credibility is much larger with free-form message communication than with restricted communication. We are the first to model this credibility and show, both theoretically and experimentally, an interaction effect of network structure and communication technologies. We also provide a model of message diffusion, which indeed predicts that diffusion will be more rapid without clustering and is consistent with our data.

Trust and communication in a property rights dilemma

We study in five diverse countries a laboratory social dilemma game in which incentives to steal from others lead to the socially inefficient diversion of resources from production unless the members of a given mini-society can abide by norms of non-theft or engage in low cost collective protection of their members’ wealth accumulations. We compare two treatments in which subjects have opportunities to exchange free-form messages to one without such opportunities, finding that most subjects allocate far less to theft and most groups achieve much greater efficiency in the presence of communication. Ease of identifying who has engaged in theft varies across the two communication treatments, but is of minor importance to the outcome. We find several coding-amenable elements of message content to be statistically significant predictors of group and individual outcomes. Contributing to the literature on culture, norms, and preferences, we find that the degree to which communication fosters cooperation varies among countries in a manner correlated with variation in survey based trust and with desistance from theft at the outset of our communication-free experiment treatment.

Watch Your Words: An Experimental Study on Communication and the Opportunity Cost of Delegation

Communication has been shown to play a positive role in promoting trust, yet there is no evidence on how sensitive this result is to the size of the gains from cooperation. To investigate this issue, we adopt an experimental design in which a trustee can send a free form message to a trustor, before the latter makes a delegation choice, by selecting whether or not to allow the trustee to decide how to share a given sum between the two of them. We allow the opportunity cost of delegation to vary and find that the trustee makes use of non-precise promises prevalently when the opportunity cost of delegation is low. Moreover, communication increases the trustor’s beliefs on the amount that the trustee will choose to transfer, only when this cost is high to start with. This attenuates the effect of the size of the opportunity cost of delegation on the trustor’s choice. We also find evidence of deception, but in some circumstances the trustee is overoptimistic about her ability to deceive. Indeed, in the presence of lower opportunity costs of delegation, we document an illusion effect: a trustee using non-precise promises incorrectly expects these to exert a positive effect on the trustor’s beliefs and propensity to delegate.

Trust and Communication in a Property Rights Dilemma

We study a laboratory social dilemma game in which incentives to steal from others lead to the socially inefficient diversion of resources from production unless the members of a given mini-society can abide by norms of non-theft or engage in low cost collective protection of their members’ wealth accumulations. We compare two treatments in which subjects have opportunities to exchange free-form messages to one without such opportunities, finding that most subjects allocate far less to theft and most groups achieve much greater efficiency in the presence of communication. Ease of identifying who has engaged in theft varies across the two communication treatments, but is of minor importance to the outcome. We find several coding-amenable elements of message content to be statistically significant predictors of group and individual outcomes.

Rich communication, social motivations, and coordinated resistance against divide-and-conquer: A laboratory investigation

This paper presents a laboratory experiment to investigate how social motivations and free-form communication (Rich Communication) can facilitate coordinated resistance against divide-and-conquer transgressions. In our experiment, a leader first decides whether to extract surplus from a victim and shares it with a beneficiary. We find that the successful joint resistance rate increases almost four-fold (from 15 to 58%) when moving from more restrictive communication treatments to Rich Communication. We also find that the significant impacts of Rich Communication are driven more by the responders' ability to send free-form messages rather than the multiple and iterative opportunities to indicate intentions.

Can Anonymous Posters on Medical Forums be Reidentified?

BackgroundParticipants in medical forums often reveal personal health information about themselves in their online postings. To feel comfortable revealing sensitive personal health information, some participants may hide their identity by posting anonymously. They can do this by using fake identities, nicknames, or pseudonyms that cannot readily be traced back to them. However, individual writing styles have unique features and it may be possible to determine the true identity of an anonymous user through author attribution analysis. Although there has been previous work on the authorship attribution problem, there has been a dearth of research on automated authorship attribution on medical forums. The focus of the paper is to demonstrate that character-based author attribution works better than word-based methods in medical forums.ObjectiveThe goal was to build a system that accurately attributes authorship of messages posted on medical forums. The Authorship Attributor system uses text analysis techniques to crawl medical forums and automatically correlate messages written by the same authors. Authorship Attributor processes unstructured texts regardless of the document type, context, and content.MethodsThe messages were labeled by nicknames of the forum participants. We evaluated the system’s performance through its accuracy on 6000 messages gathered from 2 medical forums on an in vitro fertilization (IVF) support website.ResultsGiven 2 lists of candidate authors (30 and 50 candidates, respectively), we obtained an F score accuracy in detecting authors of 75% to 80% on messages containing 100 to 150 words on average, and 97.9% on longer messages containing at least 300 words.ConclusionsAuthorship can be successfully detected in short free-form messages posted on medical forums. This raises a concern about the meaningfulness of anonymous posting on such medical forums. Authorship attribution tools can be used to warn consumers wishing to post anonymously about the likelihood of their identity being determined.

Broken Promises: An Experiment

We test whether promises per se are effective in enhancing cooperative behavior in a form of a trust game. In Charness & Dufwenberg (2006) we found considerable effectiveness for free-form personalized pre-play statements-of-intent (promises), in support of a theory of belief-dependent guilt aversion. However, we were not able to reject an alternative explanation based on a belief-independent cost-of-lying. We now adapt our old design and replace the free-form messages with an opportunity for a bare promise-only message. If both forms of promises are equally effective, this would be consistent with a cost-of-lying explanation. However, in sharp contrast to previous results, we find that these bare promise-only messages lead to behavior that is much the same as when no messages are feasible. Further, beliefs are unaffected, in contrast with the change in beliefs we found with personalized promises. This provides evidence for belief-dependent guilt aversion over cost-of-lying.

Social Learning and Norms in a Public Goods Experiment with Inter-Generational Advice1

We study a linear public goods game using an inter-generational approach. Subjects in one generation leave advice for the succeeding generation via free-form messages. Such advice can be private knowledge (advice left by one player in generation t is given only to his or her immediate successor in generation t + 1), public knowledge (advice left by players of generation t is made available to all members of generation t + 1), and common knowledge (where the advice is not only public but is also read aloud by the experimenter). Common knowledge of advice generates a process of social learning that leads to high contributions and less free-riding. This behaviour is sustained by advice that is generally exhortative, suggesting high contributions, which in turn creates optimistic beliefs among subjects about others' contributions. We suggest that socially connected communities may achieve high contributions to a public good even in the absence of punishment for norm violators. Copyright 2006, Wiley-Blackwell.

Social Learning and Norms in a Public Goods Experiment with Inter-Generational Advice

We adopt an inter-generational approach to the public goods game where one generation of subjects leave advice for the succeeding generation via free form messages. Such advice can be private knowledge (advice left by one player in generation t is given only to her immediate successor in generation t+1), almost common knowledge (advice left by players of generation t is made available to all members of generation t+1) and common knowledge (where the advice from the preceding generation is not only made public but also read aloud by the experimenter). We find that when advice is common knowledge it generates a process of social learning and norm creation that leads to high contributions over time and also mitigates problems of free riding. Such high contributions are sustained by advice that is generally exhortative, suggesting high contributions, which in turn create optimistic beliefs, especially among conditional co-operators, about the contributions to be made by other subjects. Our results suggest that socially connected communities may be able to achieve high contributions to a public good even in the absence of any punishment opportunities of norm violators.