As a “non-traditional” student, it is hard to remember how and when I learned some of the basic information in math class. I might have some visions of a chalkboard and a teacher lecturing, others might have memories of endless sheets of problems to be solved. The methods we learned many years ago might have changed for the current generation of students, and we must adjust and learn how to teach these children.
I have not used standard deviation in years and struggled while recently trying to calculate it. I started with things that I could do well, like calculating the mean of the items. After finding the mean in the set of numbers, I then subtracted the mean from each number in the set. This gave me the deviation of the specific numbers from the mean. The next steps are to square all of those deviations (differences) and add them together and then divide by the count to get the variance. (Is anyone else tired and confused by this point already?) Once you have the variance you are so close!! Keep going!! The standard deviation is computed by taking the square root of the variance.
The standard deviation is a way of knowing what is normal, and what is extra large or extra small. The standard deviation can either be negative or positive depending on whether it is smaller or greater than the mean. It is a difficult concept to understand, to say the least. I could have used this knowledge more this past year when the preschool screeners were trying to tell me where my son was compared to others who had tested. I was quite confused and couldn’t remember the reasoning behind the term and was too afraid to ask in fear of looking like an idiot. I’m glad that I can now understand the concept and inform future parents on the explanations behind the scores they might see.
Here is a website that walks you through the steps to compute the standard deviation.
No comments:
Post a Comment