For many years I asked students in my classes how they crossed their arms, either right arm over left or left arm over right. The breakdown was anecdotally almost always 50% for each, and it did not seem to depend whatsoever on what their dominant hand was. Later, I noticed that how they laced their fingers and clapped their hand also did not seem to depend on their dominant hand. Thus, I created a survey using Google Forms and asked for responses on Reddit. The following graphics summarize the results after nearly 1,000 responses.
The first image shows the results for each of the 16 combinations as indicated by the inset graphic.
The second image contains the same information but presents it in a different way.
The final image shows the breakdown between all combinations. This one contains the most detail and takes some time to digest. As an example, of the respondents, 17% of the total were left-handed. Going down the left-handed column, you see that only 13% of left-handers clapped with their left hand over their right. Thus, there may be a slight correlation between being left-handed and clapping with your right hand over your left. Note, however, that besides the zero and 100% entries, the values in each column are very close to one another. This suggests that there really is no correlation between how people do these common things.
Feel free to add your own data by following the link.
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