The world of Internet today is not far away from social networks. One way to
communicate in the cyber world is to use tools such as Instant Messengers (IM),
social networking platforms and email. Basically, IM occur in real-time and
are not supported by transaction control. However, with more advanced technology,
IM have added more functions that allow users to see each other via webcams,
or talk directly for free over the Internet using a microphone and headphones
Although, IM have many benefits, they also have some risks in their usage.
These risks include security risks (e.g., IM is used to infect computers with
spyware, viruses, trojans, worms, etc.), compliance risks, inappropriate use,
leakage of secrets, etc., (Kim and Leem, 2005; Hindocha
and Chien, 2003).
In the virtual world, people are not limited by the constraints placed on them
in the real world; this causes many cases of false identity and impersonation.
In many cybercrimes, the criminal uses services such as chat, forums, blogs
and IM programmes, to commit crime against children, fraud and identity theft.
In particular, there are many cases of people pretending to be someone else
and taking advantage of the anonymity provided by the Internet to commit crimes
(Kontostathis et al., 2010; Blair,
In a study by Hancock et al. (2004) it was found
that the rate of lies occurring in an IM conversation is about the same as a
face-to-face conversation. Approximately one-fifth of IM conversations involve
a lie. In an experiment conducted by De Turck and Miller
(1985) they found six indicators that were related to fraudulent communication.
The indicators were message period, response latency, adapter, pause, non-fluencies
and h and signals.
The increased use of online chats has opened up greater space for people with
bad intentions to commit deception. Since, detection of deception through body
language cannot be used in online chats, further studies should be conducted
to detect deception within the text format. Although, psychological studies
in detecting deception through body language (i.e., body movements, eye movements
and voice analysis) are nearly stable, there is still room for studies in deception
detection through text analysis.
Definitions of deception: Many definitions of deception have been suggested
by previous researchers. For example, lying is saying what you believe is not
true when you believe that the following norms in the conversation on effects:
Do not say what you believe is not true (Grice,
1989). This means that when you are sure that something is not true, then
dont say it; if you say it, then you are lying. Wallace
(1995) also said that deception included a scheme designed to deceive.
Someone who wants to deceive will plan their deception. That person intends
to commit a fraud.
Burgoon and Buller (1996) said that deception was
an intentional transmission of information that aimed to foster a false conclusion
or belief in the receiver. This means that if you are successful in making a
wrong conclusion in the receiver, then you have succeeded in deceiving him h-1.
This definition has been referred to by many researchers.
Meanwhile, Amos (2008) said that in practice, not all
that was said in a conversation topic of deceit was a lie. Some are truths that
are used to support the deception as a whole.
George and Carlson (1999) also suggested that deception
messages that are sent via email, chat, or instant messages, should be more
difficult to detect than those delivered by non-text media, such as telephone
or face-to-face communications.
Cues of deception in the text: There are many current studies, where
researchers have examined the cues of deception that can be obtained from text.
These cues are summarised in Table 1.
From these findings Zhou et al. (2003, 2004a,
b), Zhou (2005), Zhou
and Zhang (2007) and Zhou and Sung (2008) clustered
together nine linguistic constructs that are useful for detecting deception
in text; namely, affect, complexity, diversity, expressiveness, non-immediacy,
quantity, specificity, uncertainty and informality.
Based on Table 1, previous researchers did not determine
how much deception was considered to be more or less when compared to truthful
senders. Previous researchers only determined whether a message was deceiving
or not but did not explain how much of the message was deceiving. Therefore,
the author suggested an idea to give a percentage of possibility that a message
In order to do that, a measurement model for deception detection has been developed.
A linguistic construct was adapted in the attempt to build the model. To make
full use of the model, it was integrated into a newly developed chatting software.
It would analyse the degree of trust in chatting partners. It was also meant
to give early warnings to chatters about their chatting partners based on their
|| Tendency cues of deception
|*L: Liars; T: Truthful senders
Measurement of deception detection model: This study used Message
Feature Mining (Adkins et al., 2004) to
detect deception. Message Feature Mining is a method for classifying messages
based on intent by using content-independent message features, in which the
message features chosen are determined by the context of the classification.
The selected features should follow the proven cues of deception. The selected
features were adapted from the previously described linguistic constructs. Steps
to find the percentage of the possibility that a message is deceitful or not
will be explained in the following section.
Step 1: The first step is to determine the selected features in the text
that showed the cue that someone was deceitful or not. These features were partially
adapted from (Zhou et al., 2003, 2004b).
The selected features are grouped into five categories; as shown in Table
Step 2: As shown in Table 2, there is a need to find
the total number of words, sentences, characters, clauses, words in a noun phrase,
unique words, passive verbs, second-person pronouns, first-person singular pronouns,
first-person plural pronouns, third-person pronouns, adjectives, adverbs, nouns,
verbs and misspelled words in the conversation.
|| Selected cues to deception
Then the values of each cue are calculated using the formula shown in Table
Step 3: As stated earlier, previous researchers did not explain how
much was said to be more and how much was said to be less, compared to those
who are truthful persons. Therefore, this study will determine if the person
who told lies is less complex than those who are truthful. Then, the complexity
of each cue is determined as less than 50% and vice versa, if the person who
speaks lies is more informal than those who are truthful. Then, the value of
informality is determined as more than 50%.
To determine whether each cue is greater or less than 50%, we used the formula
shown in Table 3. The cues for an average sentence length,
average word length, average number of clauses and average number of noun phrases,
would be compared with the same cues from their chat partners.
Step 4: As shown in Table 2, there are 12 cues of
deception in the text. Assuming that all cues are important; the weight of each
cue is 8.33% (100%/12).
|| Cues percentage equation
|Lexical Diversity: Lexical Diversityx100%, Self Reference
Ratio: Self Reference Ratiox100%, Passive Voice Ratio: Passive. Voice Ratiox100%
Your Reference Ratio: Your Reference Ratiox100%, Group Reference Ratio:
Group Reference Ratiox100%, Other Reference Ratio: Other Reference Ratiox100%,
Emotiveness, Emotivenessx100%, Typographical Error Ratio: Nisbah Kesilapan
After the percentage of each cue is calculated using the equation shown in
Table 3, the weight percentage of each cue obtained is measured
using the equation shown in Table 4.
Step 5: After the percentage of each cue is found, they are summed to
calculate the total. The sum total becomes the percentage of the possibility
that the conversation partner is deceitful.
Experiment design: This experiment used the modified problem scenario
of life in the desert (Desert Survival Problem by Lafferty
and Eady (1974)). This scenario has been widely used by previous researchers
(Adkins et al., 2004; Fuller
et al., 2009; Twitchell, 2005; Zhou
et al., 2003, 2004a, b;
Zhou and Zhang, 2007; Zhou
et al., 2008; Zhou and Sung, 2008) to collect
deception data within text. This shows that this scenario is popular in collecting
deception data and therefore aligned with the needs of this study. Since this
is an early stage, the experiment used a small sample size to test the current
prototype. If the prototype reaches stability, a larger sample size would be
used to test the prototype in the future.
Participants: Participants (N = 20) were students from the Faculty of
Economics, University of North Sumatera (Male = 7, Female = 13), who received
additional marks for participating in the experiment.
Procedure: The entire experiment took place in an Economic Faculty classroom,
which had a wireless Internet connection. Each participant was required to bring
their own laptop.
|| Cue weight percentage equaction
The participants completed the experiment in the classroom by logging into
the developed chat software. R andomly paired, participants were r andomly given
the roles of either Sender
They communicated with their friends using text only via., the chat software.
The experiment session took between 50-80 min to complete. After that, participants
were asked to complete questionnaires.
Case scenario: Participants were informed that they would participate
in the study of decision making that was modified from the problems of life
in the desert (i.e., the Desert Survival Problem). This study asked the participants
to imagine that they had a jeep which crashed in the desert of Kuwait and that
there was no clean water and there were some items that could be repaired. The
items were determined by the researchers.
Role of the receiver: Participants who played the role of the Receiver
were told to define the rankings from the 12 items (e.g., mirror, compass, knife)
for their survival. They were asked to rank from number 1-12, with 1 as the
most important item to number 12 as the least important item to have. Before
interacting with their partners (i.e., the Sender), all participants were asked
to read a detailed document on what was needed to survive in the desert. This
information was taken from military field manuals (available at: http://rk19-bielefeld-mitte.de/survival/FM/13.htm).
They were used to form the basis of the ranking and the discussion.
First, participants (Receiver) were asked to determine their initial position
freely, following which they started to discuss with their partners (Sender)
on why their position (Receiver) was like that, until at its final position
to reach an agreement. Participants (Receiver) would also be informed that their
chatting partner might intend to deceive and they were told that they could
use the tools provided in the chatting software to measure the possibility that
their chat partner was being deceitful. Then they completed their final ranking
freely and completed the questionnaires given in the chatting software.
Role of the sender: Participants who were given the role of Sender
were tasked to deceive, mislead and give invalid information to the Receiver.
After reading the instructions of the general task, Sender
(or liar) received additional instructions as follows:
In addition, the main objective of this study is to learn how people
can detect false, misleading and deceptive information in communication. There
are often situations where it is NOT in the best interests of a person to tell
the truth, the whole truth and nothing but the truth-for example,
to avoid unpleasant circumstances, to protect your loved ones, or to protect
your country. A certain level of communication skill is necessary to be able
to adapt to this situation. Your instructor will ask you to mislead your partner
so that the instructor can determine how well your partner can detect your deception.
If you have any objections to performing this role, please notify the experimenter
at this time.
After reading the documents, they were asked to list the ranking contrary
to what is recommended by the experts and contrary to what you believe is true
and correct information. To
strengthen this manipulation, they were told that their task was to provide
incorrect, misleading and deceptive information to their partners and that they
should argue that communication tools such as a mirror and a flashlight were
useless in the desert and propose to leave all unnecessary clothing (e.g., rain-equipment)
and equipment to make walking easier.
They were also told that there were many ways to be dishonest, including telling
blatant lies, exaggerating, vague, indirect, unclear and ambiguous messages,
or leave and avoid discussing the relevant information. In short, they could
use their own techniques and communication style to deviate from the truth,
the whole truth and nothing but the truth.
Finally, they were told that their team members did not know that they received
special instructions and it was important not to disclose this information to
their team member both during and after the discussions.
Demographic results: As explained previously, there were seven men and
13 women who participated in this experiment. From the questionnaires completed
by the participants, all participants were aged between 20-30 years old. The
frequency of participants using online communication with other people in one
day is summarised in Table 5.
The table shows that the amount of time that the majority of participants use
online communication with others was not more than two hours per day.
Deceiver motivation: To confirm that the participants, who were given
the role as Sender,
were actually deceiving and to test the participants' motivation to deceive,
four questionnaires that were rated on a scale of 1-10 were given. The average
score of three categories were determined-low (1.0-3.3), moderate (3.4-6.73)
and high (6.74-10.0).
The reliability test of the questionnaire showed that the Cronbach's Alpha
(Cronbach, 1951) from the four questions was 0.933. Because
the value was above 0.7, this questionnaire was considered as reliable.
The result of this experiment show that participants who played the role of
Sender had a strong motivation
to succeed in deceiving their chat partner (average score = 6.90).
Table 6 shows the average scores of the four questionnaires
used to test the motivation of participants to deceive their chat partner during
Deception detection information by receiver: To examine the level to
which participants (Receiver) could determine whether their respective chat
partner was trying to deceive them or not, the researchers gave them nine questionnaires
|| Frequency of using online communications
|How much time a day that you use to communicate online with
|| Deceiver Motivation
The result of Cronbach's Alpha from the nine questions was 0.894 and because
the value was above 0.7, this questionnaire was deemed as reliable.
Table 7 indicates the value of the average scores of the
nine questions. For questions numbered 1 and 5, they were rated on a scale of
1-2. Question numbere 2, 3 and 4 were rated on a scale of 1-10, while question
numbere 6-9 were rated on a scale of 1-7.
In the questionnaires that had a value on a scale of 1-7, the researchers determined
the average score of three categories which was low (1.0-2.33), moderate (2.34-4.67)
and high (4.68-7.0).
Table 7 shows that overall, the participants in this experiment
believed in the results given from the analysis provided by the application
(average = 5.80) and had some impact on their decision (average = 6.60). However,
this table also shows that overall, they were not able to determine whether
their chat partner was deceiving (average = 1.90) and they were very confident
(mean = 4.80) with their decision. Overall, this discussion went smoothly (average
= 4.40) and participants were very comfortable during the discussion (5.00)
and understood their chat partner (4.20).
Table 8 shows how many participants, who were given the role
answered the correct answer in sorting the 12 items from the most important
to the least important item.
Table 8 shows that the participants could not sort the items
from the most important to the least important (Average = 1.00). This proves
that the participants who were given the role of Sender
had been successful in deceiving their partners who were given the role of Receiver.
Table 9 shows a comparison between the questions numbered
4, 5 and 6 (Table 7) with the percentage of possibilities
that their chat partner was deceiving which were produced by the developed application.
|| Information deception detection
|| A score of sorting 12 items
||Comparison of users perceptions with analysis produced
by the applications
This is aimed to compare the users' perception towards their chat partner was
being deceitful and the applications perceptions on which level of their
chat partner was being deceiving.
This table shows that the participant with username receiver
1 strongly believed (value =
9) that their chat partner was an honest person and had decided that the chat
partner was an honest person (value = 2) and he was very confident of his judgment
(value = 6). This was consistent with the results shown by the analysis provided
from the application that their chat partner had lied at a low level (percentage
Overall, participants' perception of their chat partner was of someone who
was honest (average = 5.60) and they had to make decisions that their chat partner
was someone who was honest (average 1.90) and they were confident in their judgment
(Mean = 4.80). The percentage provided by the application also showed that the
level of their chat partners being deceitful was shown at a low level (average
DISCUSSION AND CONCLUSION
Based on the results obtained, participants who were given the role of Sender
or given the task to deceive, mislead and give invalid information to the participants
given the role of Receiver
was a high motivation (average = 6.90) to convince them. This shows that the
participants did a good job. However, from the perceptions of participants who
were given the role of Receiver
it appeared that they were not able to determine whether their chat partner
was someone who was deceitful. This is justified by the low average value of
12 for participants who could sort the most important items to the least important
(average = 1.00).
Overall, the analysis produced by the application shows that the percentage
of the possibility a chat participant (Receiver) was deceiving amounted to 11.36%.
When compared to a medical field, if stated that the patient has a 10% risk
of cancer, this means that despite a 10% chance of cancer, it may be very risky
for the patient. This is the same as the analysis produced by the application
that even though an 11.36% chance of a chat partner was being deceitful; this
proves that there was a lie committed by the chat partner. The possibility that
the chat partner was deceitful is indicated by the percentage of 11.36%.
However, the analysis produced by the application shows that the level of possibilities
that the chat partner was being deceitful was at a low level (average percentage
= 11.36%). This indicates that this application could not accurately detect
the possibility that the chat partner was being deceitful.
This probably occurs due to the lack of decisions to determine how much is
said to be more and how much is said to be less, compared to people who are
honest. Previous studies only stated that a message is deceiving or not (Zhou
et al., 2003; 2004a, b;
Zhou, 2005; Zhou and Zhang, 2007;
Zhou and Sung, 2008; Twitchell, 2005).
Thus, the model to measure this deception determined that when the cue was said
to be more than that of honest people, then the percentage value was more than
50% and vice versa, if the cue was said to be less than someone who was honest,
then the percentage value was less than 50%. The value of this percentage may
not be suitable for each cue. Therefore, it needs further study to determine
the value of percentage of this deception detection to measure more accurately.
Previous studies only tested the effectiveness of a technique in detecting
deception in text (Burgoon et al., 2003; Depaulo
et al., 2003; Fuller et al., 2009;
Humpherys, 2010; Twitchell, 2005;
Zhou and Sung, 2008; Tiantian et
al., 2005) but did not test how effective the technique was that was
applied to the software (e.g., online chat software) could help users to make
Therefore, the results from this experiment showed that the users believed
in the analysis provided and affected their decision. This indicates that the
facilities provided in this chat software prototype could help them to make
the best decision.