## Saturday, April 18, 2015

### Unschooling Post Algorithm

To follow up on this post, I used the Facebook app algorithm to calculate the likeness score between my current self and my unschooling self, and it is 63%. I'm only 63% like my unschooling self.

Now, 63% may seem pretty alike, and I would assume that 63% was pretty alike if a friend and I came out that way. But this is my own self. The baseline with another person would be 50%, but the baseline with myself is 100%, so 63% is extremely low. To put this in perspective, my ex boyfriend and I came out 58% alike on this test, and my other close friend and I came out to be 55% alike. Both of these people are very different from me. The likeness between my current self and my unschooling self is not very much greater than my likeness with other people, which shows just how far off my current self is from the person I would have been without school and structure in my life.

A 63% match wouldn't even be recommended on OkCupid!

If you're interested, here's how the likeness algorithm works:

Back when Facebook had the My Personality App, it used to calculate your likeness score with other friends who had taken the Big Five Personality Test. Facebook only calculated this likeness score based on 5 traits. There was an explanation of the formula used to calculate the likeness score. I did the formula using all 30 traits. This likeness score is more accurate than the scores generated by the Facebook app because it uses 30 specific traits instead of 5 broad categories. Here's the formula:

1. Line up both people's scores on each trait next each other, and take the difference of the two scores on each trait.

2. Square each of the differences. Once you have squared the differences, take the sum of the squared differences:

The idea behind this is that a large difference on one trait makes you more different from the other person than a bunch of smaller differences. For example, a 50-point difference on one trait would be a much greater personality difference than a 5-point difference on each of 10 traits, even though the quantity of the difference is the same. Squaring the differences before taking the sum makes one 50-point difference count for more than 10 5-point differences.

3. Take the square root of the sum. In this case, the square root of 40,850 is 202.11.

4. Divide this number by the square root of the number of traits. In this case there are 30 traits, so 202.11/ sqrt 30 = 36.90.

The purpose of taking the square root of the sum and then dividing by the square root of the number of traits is to convert the difference score back into a number from 1-100, since each of the traits are measured on a 1-100 scale. In this case, the 36.90 is the difference score.

5. Subtract the difference score from 100 to get your likeness score. In this case, 100-36.90 = 63.10.

I used the current and unschooling conditions in this example, but you can use this formula to see how alike you are with different people. The test I used is the IPIP-300 on this website: http://www.personalityassessor.com/tests/