biostatistic1

1- Descriptive Statistics:
Summarizing the information in a collection of data by presentation its in tables, graphs, and the collection of numerical summaries such as frequencies, mean, median, etc.

2- Inferential Statistics:
Using information from a sample to make conclusions/ predictions about the population.What is Biostatistics?
Biostatistics encompasses a wide variety of applications of statistics to biological sciences, includes:
1. The design and analysis of biological experiments and surveys.
2. Quantification of biological phenomena.
3. The use of statistical principles in managing biological processes, etc.

Biostatistics originated from statistical applications for agriculture, but its scope now includes such:
1- Environmental sciences.
2- Food and water quality assurance.
3- Pharmaceutical development and risk assessment.
4- Health and international development, and any more.
Biostatistics Is defined as the application of statistical method, or mathematical logic, to analyze and understanding of biological variation.

There are two reasons to study biostatistics:
1- The study of biostatistics will help students to understand the nature of variability.
2- Biostatistics will teach how derive general law from small samples.

Statistical Definitions
Population: A population is the largest group of people or things, for example the students enrolled in Babylon University.
Sample: Is a part of population, for example the students enrolled in Pharmacy College.
Sample Size: The number of elements in the sample is called the sample size and is denoted by n.
Variable: Is defined as characteristics which show variation or variability, for examples: height, no. of drugs, educational level, no., etc.

Types of Variables:
1- Quantitative Variables:
The values of a quantitative variable are numbers indicating how much or how many of something, for examples, weights, temperatures, ages, etc.

There are two types of Quantitative Variables:
a- Discrete Variables:
Variables which are measured on discontinuous scale, for example: - Family size (x = 3)
- No. of students in Pharmacy College. (x = 500)
b- Continuous Variables:
Which are measured on continuous scale (interval), for example:
- Height (140 < x < 190) cm
- Blood sugar level (90 < x < 120) mg/dl
- Serum Cholesterol (140 < x < 160) mg/dl

2- Qualitative Variables:
The value of a qualitative variable are words or attributes indicating to which category an element of the population belong.


There are two types of Qualitative Variables:
a- Nominal Variables:
Variables which are not numeric data or in event groups, we can not arranged its. For example:
- Types of drugs (Alkaloids, Glycosides, Tannins, etc).
- Gander (male, Female).
b- Ordinal Variables:
Variables which are consist of levels or groups; we can arrange its ascending or descending. For example:
- Conc. of vit. C (Fruits, Vegetables, Nuts).
- Educational level (Bch, MSc, PhD).