Biostatguide: Recent Comments

Comment on The Variance

2008-04-26T15:02:41Z

The larger the variance, the further that individual values of the random variable tend to be from the mean, on average.
The smaller the variance, the closer that individual values of the random variable tend to be to the mean, on average.

taking the square root of the variance gives the standard deviation.

The variance and standard deviation of a random variable are always non-negative.

Comment on The Variance

2008-04-26T14:57:12Z

This is a measure of statisitcal dispersion.
Average of the squared distance of its possible values from the mean.
Gives an idea how the spread of the values.
It is a way to capture the degree of spread.
The unit of variance is the square

Comment on Range

2008-04-25T02:37:29Z

Definition of Range:

It is the difference between the largest and smallest data in a sample.

Comment on Computation of the Mode

2008-04-25T01:46:32Z

Mode is 3

Comment on Mode

2008-04-25T01:38:28Z

Most frequently occuring vlue among the data.

Comment on Negatively skewed

2008-04-25T01:36:14Z

Data is skewed to the left.
Data points are below the median.
Data points are to the left.

Comment on Positively skewed

2008-04-25T01:34:33Z

Data points are away from the median.
Moving to the right side and above the median.

Comment on Distribution is symmetric

2008-04-25T01:19:42Z

If the data is symmetric mean, median and mode are the same

Comment on Median

2008-04-23T02:46:37Z

If the list has an even number of entries, the median is equal to the sum of the two middle (after sorting) numbers divided by two

Comment on Weakness of the Median

2008-04-23T02:31:32Z

Median is determined by middle points in a sample.
Less sensitive to the actual numeric values of the remainng numbers.