By convention, specific symbols represent certain sample statistics. For example, 1  x refers to a sample mean. 2  s refers to the standard deviation of a sample. 3  s 2 refers to the variance of a sample. 4  p refers to the proportion of sample elements that have a particular attribute.or example, 1  P refers to a population proportion; and p, to a sample proportion. 2  X refers to a set of population elements; and x, to a set of sample elements. 3  N refers to population size; and n, to sample size.
The brain is one of the most important organs in the body and gives humans the capacity for language, art, and rational thought. A brain surgeon, or neurosurgeon, is a doctor that performs surgery on the nervous system, particularly the brain. He or she will also treat a wide range of problems affecting the central nervous system is the job of a brain surgeon.
To become a brain surgeon you need to take the following steps: 1.) Graduate from high school and apply and get accepted to a university. 2.) At a 4 year university you will work towards a bachelors degree in pre-medicine or pre-health with at least a GPA of 3.5 or better.