TutorChase logo
CIE IGCSE Maths Study Notes

9.1.1 Data Classification

In the realm of statistics, accurately classifying and organising data is crucial for a comprehensive analysis. This section delves into tally tables for frequency counts and the construction of two-way tables, essential tools for organising data efficiently. By examining these concepts through practical examples, students will gain a solid understanding of how to manage and interpret data effectively.

Tally Tables for Frequency Counts

Tally tables are a fundamental method for counting and categorising data in statistics. They provide a visual representation of data frequency, making it easier to understand and analyse patterns.

Tally Table for Frequency Counts

Concept and Structure

  • Tally Marking: A simple method of recording counts using marks. Every fifth mark is typically drawn diagonally across the previous four, making it easy to count by fives.
  • Organisation: Tally tables are organised into columns, usually with the data categories on the left and the corresponding tally marks on the right.

Example: Fruit Consumption Tally

Imagine conducting a survey on the different fruits consumed in a week. The fruits identified are apples, bananas, oranges, and grapes.

Fruit Consumption Tally

In this table, each fruit type is listed with its corresponding tally marks and total frequency. For instance, grapes were consumed 9 times, represented by two groups of tally marks and an additional single mark.

Constructing Two-Way Tables

Two-way tables provide a structured method to organise data that fits into two categories, enabling the analysis of relationships between them.

Two-Way Table

Concept and Usage

  • Definition: A two-way table organises data into rows and columns, facilitating the comparison between two different categories.
  • Purpose: Useful for examining the relationship between two variables and understanding how they interact with each other.

Example: Fruit Consumption by Gender

Consider extending the fruit consumption survey to analyse the consumption based on gender.

Two-Way Table for Fruit Consumption by Gender

In this two-way table, the consumption of each fruit is categorised by gender, providing clear insights into the preferences and consumption patterns across different groups.

Practical Application

Question: Analysis of Weekly Fruit Consumption

Following the data collected in the survey mentioned above, answer the following:

1. What is the total number of fruits consumed in a week?

2. Which fruit is the most popular among females?

3. Calculate the ratio of male to female consumers for oranges.

Solution:

1. Total Fruit Consumption: By adding the totals for each fruit, we find that 30 fruits were consumed in total.

2. Most Popular Fruit Among Females: By examining the 'Female' column, grapes have the highest count at 4, making it the most popular fruit among females.

3. Male to Female Ratio for Oranges: There were 5 male consumers and 3 female consumers for oranges, leading to a ratio of 5:3.

Incorporating Equations and Calculations

While tally tables and two-way tables primarily involve counting and organisation, incorporating basic equations can enhance data analysis. For example, calculating percentages, ratios, and averages can provide deeper insights into the data collected.

Calculating Percentages

To calculate the percentage of each fruit consumed:

Percentage=(Frequency of FruitTotal Fruits Consumed)×100\text{Percentage} = \left( \dfrac{\text{Frequency of Fruit}}{\text{Total Fruits Consumed}} \right) \times 100

For apples:

(530)×100=16.67%\left( \dfrac{5}{30} \right) \times 100 = 16.67\%

Applying this formula to each fruit reveals the distribution of fruit consumption in percentage form, offering a clear perspective on preferences.

Engaging with Data through Visual Representation

Creating visual representations such as bar graphs or pie charts based on the data in tally and two-way tables can further enhance understanding and analysis. Visual tools allow for quick comparison and spotting of trends, crucial for effective statistical analysis.

Hire a tutor

Please fill out the form and we'll find a tutor for you.

1/2
About yourself
Alternatively contact us via
WhatsApp, Phone Call, or Email