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Let me begin with a confession: the “Coefficient of Group Cohesion” (CGC) is a pseudo-scientific term that I came up with in order to make a very simple concept sound more academic. However, I make no apologies for this. After all, if making up pseudo-scientific terms were a crime, most social scientists would very quickly find themselves in jail! In this article, I will try to explain what the “Coefficient of Group Cohesion” is and why I think language teachers need to be interested in it.

Like any teacher, I began to notice early on in my career that some of the classes I taught were more successful than others. I am not talking here about individual lessons, but rather about series of classes with a particular group of learners. This phenomenon was particularly noticeable in Japanese university classes where I was teaching the same material using the same lesson plan to different groups of students. In these situations, I inevitably found that one of the classes became my “favourite.” I also noticed that learning outcomes in my favourite classes were better than in the others, even if the level of the students had initially been lower. After teaching a group of classes where this difference was particularly pronounced, I began to wonder what it was about my favourite group that made the class so successful. After much observation and reflection, I came to the realisation that the key factor was not my relationship with the students, but their relationships with one another. My favourite class was successful because everyone knew and got on really well with everyone else. There were also a couple of “characters,” which always helps!

Anyway, I started thinking of ways in which it might be possible for me to measure the degree to which each class got along. I thought that if I could find a way of assessing how well a group was socialised, it would help me decide how much time and effort I would need to dedicate to that side of things during the course. The idea I came up with was the “Coefficient of Group Cohesion,” which was essentially a numerical representation of the “cohesiveness” of each group of learners.

To calculate the CGC, I first asked each student to draw a map of the classroom using circles to represent people. In each circle, I asked them to write a “point value” representing how well they knew the student that the circle represented. The explanation I gave them was as follows.

0 points: Don’t know their name; never spoken to them.
1 point: Know their name, but never spoken to them.
2 points: Spoken to them in class, but not outside.
3 points: Speak to them regularly outside the class.

When they had finished, I asked each student to calculate the total number of points on their chart. I then collected these scores, added them together, and wrote the total number on the board for everyone to see. After that, it was just a simple matter of working out the score as a percentage of the maximum possible. For example, if a class had 20 students, the maximum possible score for every student was 60 (3 points for every student) times 19 (no points for yourself, obviously), which equals 1,140 points. If the actual total of points given was 570, then the Coefficient of Group Cohesion was 50%. Simple!

Another way of working out the CGC might be to use a points system where negative scores are given for people a student doesn’t like. The scale might look something like this:

2 points:
I know and like this person.
1 point:
I don’t know this person, but I feel positively disposed to them based on their appearance.
0 points:
I do not know this person, and I have no feelings about them either way.
-1 point:
I do not know this person, but I feel negatively disposed to them based on their appearance.
-2 points:
I know this person, and I do not like them.

This system might actually produce a more accurate result, but there are obvious ethical problems with asking students to say that they do not like other members of their class. If you chose to calculate the CGC in this way, you would have to make sure that scores were collected anonymously. A major benefit of the original system is that it contains no value judgements, just simple factual assessments of how well people know each other.

So, is it really worth going to all this trouble to work out a number? I believe that it is definitely worth taking a small amount of time (the whole process normally takes around ten minutes) to find out something that I believe to be one of the strongest indicators of the likelihood of success in any given class. If I find that the CGC for a class is particularly low, I like to take one lesson to allow students to socialise in their own language. I give them a basic question, such as “How do you feel about learning English?” and ask them to discuss their answer in Japanese with as many people as possible before the end of the lesson. Allowing them to socialise without the pressure or embarrassment of having to speak English greatly increases the chance of a successful learning outcome for everyone. I also like to play a name-remembering game so that everyone tries to learn everyone else’s name within a 90-minute period. Having done all this, it is interesting to measure the CGC again at the beginning of the next class, as it will (hopefully!) have gone up significantly.

Although I have never used the CGC for anything other than improving my own classes, I have often thought that the concept could provide the basis for some interesting research. For example, a group of teachers could be asked to identify their “favourite” or most successful class. Those teachers could then be asked to work out CGCs in all of their classes to see if the ones they identified as being the most successful were also the ones with the highest CGCs. If such a relationship were shown to exist, it would provide a strong argument for devoting more time to allowing the students to socialise in their own language.

Please let me know if you have any thoughts or comments on this topic.

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  1. Koji on Wednesday June 6th, 2012 at 11:04 PM

    Hello, I am a high school teacher of English and I am your student now.
    The topic of CGC was intriguing though a little difficult for me. As a high school teacher, I teach one material at various classes, like you. From my experience, I also have realized that each class has each character. Some classes made me feel relaxed and comfortable whereas some classes made me feel stressful and nervous, just same as your experiences. As I recall, the main point was whether I made good human relations with students. However, I did not know that the relationships among the students are also very important.
    I have not measured the relationships by using CGC. I think no teacher around me has tried it yet, because it might ethical problems as you told.
    But trying such a scientific measuring seems to become more important in the future.

  2. David Barker on Wednesday June 6th, 2012 at 11:56 PM

    Hi Koji,

    Thanks for your comment. I think that one problem of being a teacher is that we tend to think that the world (or at least the classroom) revolves around us. I always used to think of there being two entities in the classroom: me and the students. That was natural, because that was the way it seemed from my standpoint. When I started taking French classes last year, however, I realized that there were actually around 15 entities in the class, and the teacher was just one of them. Even though she was standing in the middle and leading the class, she was no more or less important to me than any of my classmates.

    The reason I was able to figure out the secret of my “favourite” class all those years ago was that they were an extreme case. Everyone was great friends with everyone else, and they used to hang around with each other all day in school and then go out together at night and at the weekends. They didn’t just know one another’s names, they knew everything from birthdays to vital statistics!

    As I mentioned in the entry, I think there might be ethical problems if you used a negative points system to calculate the CGC. However, I cannot see any particular issues with the original system because you are basically just asking how well students know their classmates. I have deliberately worded the point scale so that it avoids the need to give opinions or make value judgements.

    Anyway, I’m glad you liked the article. Please let me know if you decide to try working out the CGC of any of your classes 🙂

  3. YU on Tuesday June 12th, 2012 at 06:45 PM

    Hi David,

    You have a unique idea!

    Reading this entry(CGC), I rememberd what you mentioned before ;
    You told me that it is more effective to practice English with other Japanese people than with native speakers, because Japanese people share a language and cultural background, so we will have much more to talk about.

    > I came to the realisation that the key factor was not my relationship with the students, but their relationships with one another. My favourite class was successful because everyone knew and got on really well with everyone else. There were also a couple of “characters,” which always helps!

    I exactly know what you mean.

    I used to go to a major English school which was famous for its a pink rabbit mascot character.
    They were featuring the small class sizes and the appointment system that allowed students to schedule and attend at their convenience.

    At first, I was excited at the prospect of getting to know many people at class, but soon I got tired of meeting different people every time.
    I always had to introduce myself to other students and of course, I had to listen to theirs too.

    After all, I learned that the conversation (at class)hardly ever become lively with people you have just met.

    See you !

  4. Chris on Wednesday June 13th, 2012 at 10:54 AM

    I think this right on. This quarter more students voluntarily gave speeches because they were a close group.

  5. David Barker on Friday June 15th, 2012 at 11:07 AM

    Hi YU and Chris. Thanks for your comments. I’m glad you liked the article.

  6. Mark on Friday June 22nd, 2012 at 12:29 PM

    David, interesting concept and well explained. Really enjoyed the post.

    I’d say the CGC is particularly important for language classes because success in language learning relies on the learners actually using the language. In Japan, as you well know, students get little opportunity to use English outside of the classroom, so the classroom becomes an extremely important context in which students can practice their skills. If the CGC is low students will not feel comfortable interacting with one another, thus creating a crappy atmosphere in class and low levels of success. In other types of classes (engineering, computer science, etc.) the CGC is probably not as relevant because interaction with others is not so important.

    Anyway, interesting idea you’ve come up with here. If I decide to research it a bit in my own classes I’ll be sure to give you proper credit and let you know how it goes.

  7. David Barker on Friday June 22nd, 2012 at 01:28 PM

    Hi Mark,

    I was a bit worried that this idea was too simple and obvious to write about in a blog, so I’m glad that you found it useful. Please let me know if you do any research on it.

  8. Rick on Friday September 21st, 2012 at 10:19 AM

    I too found this very interesting. I very much like the idea of devising simple ways of turning vague feelings into numerical values, provided of course that we don’t canonise the particular system we come up with. I’d be interested in hearing, perhaps in a follow-up post sometime, how you do the name-remembering game.

  9. David Barker on Friday September 21st, 2012 at 01:47 PM

    Hi Rick,

    Thanks for your comment. Funny you should mention remembering names; that will be the topic of the next post, which will be coming in the very near future. If you are on Facebook or Twitter, please look us up. If you follow us there, you will be alerted when new blog entries are posted.