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[screen shot]

If clicking does not initiate a download, try right clicking or control clicking and choosing "Save" or "Download".(The run link is disabled for this model because it was made in a version prior to NetLogo 6.0, which NetLogo Web requires.)


There are many studies looking at the impact of how role models affect the society or the individual. Role models are indeed important and influential in a community or a small group. Role models can decrease negative influences perceived by individuals (Ferguson, 2012), improve learning styles of students (Shein & Chiou, 2011), shape the behaviors of children (Sirikulchayanonta, edsee, Shuaytong, & Srisorrachatr, 2011), and even increase the satisfaction for adult workers (Healy et al., n. d.).

However, role-models may also cause negative influences to the society. When the values of the role-models are incongruent with the values of the population, there is a decrease in motivation level (Lockwood, Jordan, & Kunda, 2002). Role-models with negative influences, such as actors in Hollywood movies, increase the rate negative activity (i.e. smoking) practiced by the population (Escamillia, Cradock, & Kawachi, 2000).

Every individual has their own role-models. One type of role-model that is impactful to the society is fashion models portrayed by the media. Women who compare their figures with the figure of the fashion models normally have poorer self-esteem (Brenner & Cunningham, 1992). Similarly, if the individual’s self-perception of their own figure is poorer than the perception of fashion model’s figure, the individual will have a lower self-esteem (Prosavac & Prosavac, 2002). Thus, fashion models portrayed by the media can affect the self-esteem and the perception of the individual’s own body (Grabe, Ward, & Hyde, 2008).

The purpose of this agent-based model is to create a simple model to investigate what would occur if the fashion model loses influence, and how this process where the model loses influence affect others in terms of their self-esteem. In the model, activity refers to an arbitrary term. The distance from the individual to another individual or the fashion model used in this model is the social distance. Social Distance is the distance between people within a given location (Latané, Nowak, Bonavento, & Zheng, 1995).


**An agent either has an activity, or not. Activity is an arbitrary term.** E.g. Activity can be 'dieting'.

* **Surrounding Influence**
An agent looks at their neighbors. The agent then computes the influence value of the neighbors having the activity. To decide if the agent will perform the activity, the agent adds the influence value of the surrounding turtles: `sum ([influence] of turtles in-radius 2 with [activity? = true] / num-agents`, where _num-agents_ is the number of agents in the surrounding.

* **Fashion Model introduced**
When you pressed the "pick a random fashion-model", you introduce a fashion model. This fashion model is coloured “Red”. The countdown timer for the fashion model begins. If the influence value of the fashion model is larger than the surrounding influence, area `[ask turtles in-radius influence-radius]` where influence-radius is how far the fashion model can influence, agents within the influential become susceptible to the activity introduced by the fashion model. When the agents begin to follow the activity, these agents have a negative self-esteem `[set self-esteem -1]`.

* **When Role-model loses power / effect**
The countdown timer for the fashion model eventually reaches 0. When that happens, the fashion model loses her power or influence. When the role-model loses power, his influence is computed using: `role-model-influence / (square of distance toward role-model) `. This calculation is adapted from the Social distance formula, as proposed by Nowak et al., (1990).

let x one-of turtles with [immuned? = true] ;; Fashion-models immuned when dead
let z distance x
if z = 0 [set z 1]
set Role-model-lost-effect (Fahsion-model-influence / z ^ 2)

* **Agents decide whether to continue activity**
If `Role-model-lost-effect > surround-activity`, the impact of the role-model losing influence while doing the activity is more than the influence of the surrounding doing the activity, the agent decides not to continue with the activity.

* **Determine Self-esteem**
This portion of the calculation is adapted from the code by Nigel Gilbert (see related models). After the fashion model no longer influences the agents, all the agents begin to consider the self-esteem values of their surroundings. If the surrounding self-esteem values are higher than the self-esteem values of the individual, the individual is affected by the surroundings.


1.Press **Setup** to create the agents.

* Influential-radius: How far can the role-model influence
* Health: The health of the role-model. This value will decrease as the simulation runs. When the value reaches 0, the role-model dies.

2.Press **Go** to begin simulation.

3.Click on **Pick random Fashion model** to introduce a new fashion model into the simulation.


This model was designed for only 1 fashion model to be introduced into the simulation. Thus, adding more fashion models will not make the computation accurate.


Do you think whether the radius of influence will affect the activity of the agents after the Role-model is gone?

What happens if the size of the world is smaller / larger? Is there a difference in the results?

What if the fashion-model-influence is smaller / larger? How do you think this will affect the agents?

What do you notice about the self-esteem and activity (green agents) if the influence is very large?


* Adapt the model to different situations aside from looking at role-models
_E.g. If you intend to model a disaster, the role-model becomes the disastrous event and you can then observe the aftermath of the disaster._

* Give more variables to the agents, such as resistance to Role-model influence, the strength of an agent's own influence etc (_see related models_).


This model uses an equation which is the Social Distance Model proposed by Nowak et al, (1990); The Community Model which adapts the similar equation is done by Nigel Gilbert


Brenner, J. B., & Cunningham, J. G. (1992). Gender differences in eating attitudes, body concept, and self-esteem among models. Sex Roles, 27(7), 413-437.

Escamilla, G., Cradock, A. L., & Kawachi, I. (2000). Women and smoking in Hollywood movies: a content analysis. American Journal of Public Health,90(3), 412.

Ferguson, C. J. (2012). Positive Female Role-Models Eliminate Negative Effects of Sexually Violent Media. Journal Of Communication, 62(5), 888-899. doi:10.1111/j.1460-2466.2012.01666.x

Grabe, S., Ward, L. M., & Hyde, J. S. (2008). The role of the media in body image concerns among women: a meta-analysis of experimental and correlational studies. Psychological bulletin, 134(3), 460.

Healy, N., Cantillon, P., Malone, C., & Kerin, M. (n.d). Role models and mentors in surgery. American Journal Of Surgery, 204(2), 256-261.

Lockwood, P., Jordan, C. H., & Kunda, Z. (2002). Motivation by positive or negative role models: regulatory focus determines who will best inspire us. Journal of personality and social psychology, 83(4), 854.

Nowak, A., Szamrej, J., & Latané, B. (1990). From private attitude to public opinion: A dynamic theory of social impact. Psychological Review, 97, 362 – 376

Posavac, S. S., & Posavac, H. D. (2002). Predictors of women's concern with body weight: the roles of perceived self-media ideal discrepancies and self-esteem. Eating Disorders, 10(2), 153-160.

SHEIN, P., & CHIOU, W. (2011). TEACHERS AS ROLE MODELS FOR STUDENTS' LEARNING STYLES. Social Behavior & Personality: An International Journal, 39(8), 1097-1104.

Sirikulchayanonta, C., edsee, K., Shuaytong, P., & Srisorrachatr, S. (2010). Using food experience, multimedia and role models for promoting fruit and vegetable consumption in Bangkok kindergarten children. Nutrition & Dietetics, 67(2), 97-101.

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