Statistics & Data Interpretation
Interpret charts, graphs, averages, and statistics confidently
Learning Objectives
- Calculate and compare mean, median, mode, and range
- Read and interpret scatter plots, double-column graphs, and pie charts
- Understand the impact of outliers on central tendency
- Analyse student data tables and make comparisons
Section 1: Types of Data and Tables
Data can be categorical (labels) or numerical (numbers). Tables are used to organize data into rows and columns for easy comparison.
Section 2: Calculating Mean, Median, Mode, and Range
Averages represent central data patterns. Mean is the sum divided by the count. Median is the middle value when sorted. Mode is the most frequent value. Range is the difference between highest and lowest.
Averages Quick Guide
| Average | Method | Pros | Cons |
|---|---|---|---|
| Mean | Sum / Count | Uses all data points | Sensitive to extreme outliers |
| Median | Middle sorted value | Not affected by outliers | Takes time to order large sets |
| Mode | Most frequent | Easy to identify | Can have multiple or no modes |
Calculating Mean and Median of Student Assessment Scores
Section 3: Reading Column, Bar, and Line Graphs
Column graphs show vertical bars, bar graphs show horizontal bars. Line graphs connect data points and are useful for showing trends over time.
Section 4: Interpreting Sector (Pie) Graphs and Sector Percentages
Pie charts represent parts of a whole (100% or 360°). Each sector's size is proportional to the quantity it represents.
Section 5: Double Graphs and Scatter Plots
Double graphs compare two sets of data side-by-side. Scatter plots show the relationship (correlation) between two variables.
What is the mean of 2, 4, 6, 8, 10?