1. BIOSTATISTICS – A TOOL FOR RESEARCH AND DATA ANALYSIS PRESENTED BY SABA BUTT

2. SIGNIFICANCE OF STATISTICS FOR ANALYSIS AND RESEARCH

4. BIOSTATISTICS THE STATISTICS IN LIFE SCIENCES

6. SOME IMPORTANT DEFINITIONS

10. The Arithmetic Mean or Mean is what is commonly called the average: When the word "mean" is used without a modifier, it can be assumed that it refers to the arithmetic mean. The mean is the sum of all the scores divided by the number of scores. Formula of calculating Population Mean is: μ = ΣX/N, where μ = population mean, and N = number of scores . If the scores are from a sample , then the symbol X refers to the mean and n refers to the sample size , formula written as: X = ΣX/n.

11. Median: The median is the middle of a distribution: half the scores are above the median and half are below the median. The median is less sensitive to extreme scores than the mean and this makes it a better measure than the mean for highly skewed distributions . 5 3 4 2.5 6 Mode: The mode is the most frequently occurring score in a distribution and is used as a measure of central tendency. The advantage of the mode as a measure of central tendency is that its meaning is obvious. 5 3 4 5 6

15. Subject No. BMI Subject No. BMI