1. Introduction to Statistics:
● Statistics is the branch of mathematics that deals with the collection, analysis,
interpretation, presentation, and organization of data.
2. Types of Data:
● Qualitative Data: Categorical data that can be grouped into categories.
● Quantitative Data: Numerical data that can be measured.
3. Descriptive Statistics:
● Measures of Central Tendency:
○ Mean: The average of a set of values.
○ Median: The middle value in a data set.
○ Mode: The value that occurs most frequently.
4. Variability:
● Range: The difference between the maximum and minimum values in a data set.
● Interquartile Range (IQR): The range of the middle 50% of the data, calculated as
the difference between the third quartile (Q3) and the first quartile (Q1).
5. Measures of Spread:
● Variance: A measure of how spread out the values in a data set are.
● Standard Deviation: The square root of the variance; it provides a more
interpretable measure of the spread.
6. Graphical Representations:
● Histograms: A visual representation of the distribution of a dataset.
● Box-and-Whisker Plots (Boxplots): A visual summary of the distribution of a
dataset.