Creepiness

Creepiness is the state of being creepy, or causing an unpleasant feeling of fear or unease. A person who exhibits creepy behaviour is called a creep. Certain traits or hobbies may make people seem creepy to others. The internet has been described as increasingly creepy. Adam Kotsko has compared the modern conception of creepiness to the Freudian concept of "unheimlich". The term has also been used to describe paranormal or supernatural phenomena.
History and studies.
In the abstract the feeling of "creepiness" is subjective: for example some dolls have been described as creepy.
During the 20th century, association was made between involuntary celibacy and creepiness.
The concept of creepiness has only recently been formally addressed in social media marketing.
Causes.
The state of creepiness has been associated with “feeling scared, nervous, anxious or worried”, “awkward or uncomfortable”, “vulnerable or violated” in a study conducted by Watt et al. This state arises in the presence of a creepy element, which can be an individual or, as recently observed, new technologies.
Individuals.
Creepiness can be caused by the appearance of an individual. 
A study by McAndrew et al. investigated the characteristics that make people creepy. Creepy people were thought to be more often male than female by an overwhelming majority of participants (around 95% of both males and females participants). Another study conducted by Watt et al. also found that participants associated the ectomorphic body type (more linear) with creepiness, more than the other two body types (51% vs mesomorphic, 24% and endomorphic, 23%). Other cues of creepiness included low hygiene, especially according to female participants, and a dishevelled appearance . Participants also identified the face as an area with potentially creepy features: in particular the eyes and the teeth. Both of those physical features were deemed creepy not only for their unpleasant appearance (ex. squinty eyes or crooked teeth) but also for the movements and expressions they engaged it (ex. darting eye movements and odd smiles). 
In fact, appearance doesn’t seem to be the only factor making an individual creepy: behaviours provide cues as well. Behaviours such as “being unusually quiet and staring (34%), following or lurking (15%), behaving abnormally (21%), or in a socially awkward, "sketchy" or suspicious way (20%)” are all contributing to a feeling of creepiness, as described by Watt et al.’s study.
Technology.
In addition to other individuals, new technologies, such as marketing’s targeted ads and AI, have been qualified as creepy.
A study by Moore et al described what aspect of marketing participants considered creepy. The main three reasons are the following: using invasive tactics, causing discomfort and violating of norms. Invasive tactics are practiced by marketers that know so much about the consumer that the ads are “creepily” personalised. Secondly, some ads create discomfort by making the consumer question “the motives of the company advertising the product”. Finally, some ads violate social norms by having inappropriate content, for example by unnecessarily sexualizing it.
It is marketing’s extensive knowledge used in an improper way, together with a certain loss of control over our data, that creates a feeling of creepiness. 
Another creepy aspect of technology is human looking AI: this phenomenon is called the uncanny valley.
Humans find robots creepy when they start closely resembling humans. It has been hypothesised that the reason why they are viewed as creepy is because they violate our notion of how a robot should look. A study focusing on children's responses to this phenomenon found evidence to support the hypothesis.
Evolutionary explanation.
Several studies have hypothesized that creepiness is an evolutionary response to potentially dangerous situations. It could be linked to a mechanism called agency detection which makes individuals expect malignant agents to be responsible for small changes in our environment. McAndrew et al. illustrates the idea with the example of a person hearing some noises while walking in a dark alley. That person would go in high alert, fearing that some dangerous individual was there. If that wasn’t the case the loss would be small. If, on the other hand, a dangerous individual was actually in the alley and the person had not been alerted by this creepy feeling, the loss could have been significant. 
Creepiness would therefore serve the purpose of alerting us in situations in which the danger isn’t outright obvious but rather ambiguous. In this case, ambiguity both refers to the possible presence of a threat and to its nature, sexual or physical for example. Creepiness “may reside in between the unknowing and the fear” in the sense that individuals experiencing it are unsure if there truly is something to fear or not. Truth is that creepy characteristics are not simply caused by threat potential: in fact, ectomorphic body types are not the most powerful bodies and facial expressions are not a proxy of physical strength either. Therefore, creepiness isn’t only related to how threatening a characteristic is, in the sense of how dangerous and strong the individual can be. There are more facets to consider.
Another characteristic of creepiness is unpredictable behaviour. Unpredictability links back to this idea of ambiguity. When an individual is unpredictable it isn’t possible to tell when his behaviour will turn violent: this adds to the ambiguity of a potentially dangerous situation. This theory is endorsed by studies. Not only is unpredictability directly listed as a creepy characteristic, but other behaviours, such as norm-breaking behaviours are indirectly linked with unpredictability. Such behaviours show that the individual doesn’t conform to some social standards we would expect in a given situation. For example, we previously mentioned staring at strangers or lack of hygiene: those are behaviours that make us uneasy, creeped out, because they don’t fit the norm and therefore we don’t expect them. More generally, participants tended to define creepiness as “different” in the sense of not behaving, or looking, socially acceptable. Such differences point towards a “social mismatch”. 
Humans have a natural system of detection of such mismatch: a physical feeling of coldness. When an individual is creeped out, they report feeling those “cold chills”. This phenomenon has been studied by Leander et al, with relation to nonverbal mimicry in social interactions, meaning the unintentional copying of another’s behaviour. Inappropriate mimicry may leave a person feeling like something is off about the other. Absence of non-verbal mimicry in a friendly interaction, or the presence of it in a professional setting, raises suspicion as it doesn’t follow the norms. Individuals are left wondering what other unusual behaviour the other might engage in.