Editing Vested interest (communication theory) (section)

==Relevant research==
===Drinking age experiment===
Various studies have been conducted to determine the effects of vested interest on attitude strengths. In one such study, Crano and Sivacek<ref name="S&C"/> visited a university in Michigan and gathered the results of a proposed drinking-age referendum. The referendum sought to increase the legal drinking age from 18 to 21. The respondents were divided into three categories: 1. high vested interest (those who would be significantly and immediately affected as a result of the referendum), 2. low vested interest (those who would be unaffected by the law change at the time of its inception), and 3. moderate vested interest (those who fell between the first two extremes). Although 80% of the subjects were opposed to the referendum, their respective levels of vested interest clearly indicated that the strength of their attitudes significantly affected their resultant behaviors. Half of the highly vested interest groups joined the anti-referendum campaign, but only a quarter of the moderately vested interest group and an eighth of the low vested interest group joined the campaign.<ref name="S&C"/> These results support Crano's theory of vested interest and reinforce the implications and considerations of stake, salience, certainty, immediacy, and self-efficacy discussed above. It also proves the correlation between vested interest and action, based on what level of involvement the three types of students were willing to participate in.

===Comprehensive exam experiment===
In a second study, Sivacek and Crano<ref name="S&C"/> visited [[Michigan State University]]. In this experiment, subjects were informed that the university was considering the addition of a senior comprehensive examination to the graduate prerequisites. Respondents were given the following options:
#Do nothing
#Sign an opposing petition
#Join a group that opposed the referendum
#Volunteer specific numbers of hours to the opposing group's activities
The respondents were grouped into the same three categories as the drinking age study: high, moderate, and low vested interest. The study found that those with the highest levels of vested interest were significantly more inclined to take action based on their attitudes concerning the issue; that is, their resultant behaviors (signing the petition, joining the group, pledging multiple hours with the group) occurred much more consistently and prevalently than that of the other two vested interest groups.<ref name="S&C"/>

===Assumed consensus===
Crano conducted another study to prove that vested interest may affect people's belief that a majority of a population will support their attitude on an issue. This bias is known as [[False consensus effect|false-consensus]] or assumed-consensus effect. Under the guise of a public opinion survey, Crano<ref name="Crano83">{{cite journal | last1 = Crano | first1 = W. D. | year = 1983 | title = Assumed consensus of attitudes: the effect of vested interest | journal = Journal of Applied Social Psychology | volume = 9 | pages = 597–608 | doi = 10.1177/0146167283094009 | s2cid = 144974566 }}</ref> created high and low vested interest groups by identifying whether upper- or lower-classmen would pay a surcharge to subsidize lost funding from the government. The class who was selected to pay the surcharge had a high degree of vested interest while the student body not required to pay exhibited a lower degree of vested interest. The study then determined the participants estimate of what percentage of the student body would support their beliefs regardless of impact. Crano found that vested interest influenced assumed consensus and students believed that a majority of the university's population would support their plight even though only half would be affected.<ref name="Crano"/>

===The effect of smoking on attitudes toward cigarette tax and smoking restrictions===
Dale Miller and Rebecca Ratner<ref name="M&R">{{cite journal | last1 = Miller | first1 = D. | last2 = Ratner | first2 = R. | year = 1998 | title = The Disparity Between the Actual and Assumed Power of Self-Interest | journal = Journal of Personality and Social Psychology | volume = 74 | issue = 1| pages = 53–62 | doi = 10.1037/0022-3514.74.1.53 | pmid = 9457775 }}</ref> conducted this study utilizing 81 male and female students at the University of Yale. In this experiment the objective was for half of the participants to show their own attitude toward smoking policies and the other half to show their thoughts on others attitudes toward smoking policies. The group with the questionnaire regarding their personal attitude about smoking were asked: 1. if they were a smoker or a nonsmoker, 2. how heavy or light a smoker they were, 3. whether they would support an increase on cigarette tax, 4. would they do away with smoking advertisements, and 5. their thoughts on smoking restrictions in public places. The second half of the participants were asked what percentage they thought smokers would support the previously mentioned policies for smokers or nonsmokers. They were not asked whether or not they smoked. The results of this study replicated Green and Gerkin's 1989 study<ref>Green, D., & Gerken, A. (1989). Self-interest and public opinion toward smoking restrictions and cigarette taxes. Public Opinion Quarterly, 53, 1-16</ref> that nonsmokers had more support for smoking restrictions than did those that smoke.<ref name="M&R"/> These results supported the hypothesis: "Smokers in this study were more opposed to policies that regulated smoking than were nonsmokers, but the effect of smoking status on expressed attitudes was significantly less than that predicted by respondents".<ref name="M&R"/> The smokers had a higher vested interest in smoking policies because they were directly affected. This study also revealed a direct correlation between vested interest and attitudes.<ref name="M&R"/>

===Voter Registration===
Barbara Lehman and William Crano conducted a study regarding the persuasive effects of vested interest on attitude concerning political judgment which was published in 2001.<ref name="Lehman & Crano" /> In this study, they utilized data from 1976 national election studies concentrating on three areas (e.g. living conditions, health insurance and school integration).  Their discoveries were such that self-interest was a significant contributor to values placed on all three areas of concern.<ref name="Lehman & Crano" /> Further, outside analysis of the study revealed self-interest had a direct correlation to ideologies, affiliation, and intolerance.  Additionally, respondents with vested interest in any one of the three areas were more than likely to endorse candidates whose focus was in that particular area.<ref name="Lehman & Crano" />

	These findings, set in 1976, show a significant relationship between vested interest and aligned values associated with electoral candidates which can be either perceived or marketed.  Understanding these values, one can conclude, would allow for use of vested interest harvested by surveys to decide which values to champion for use in maximizing voter endorsement.<ref name="Lehman & Crano" />