4.5.6 Working with Statistical Diagram
Interpreting:
Interpreting statistical diagrams involves understanding the information presented in the graph
or chart and make inferences about the data.
Here are some general steps you can follow to read and interpret statistical diagrams:
Identify the type of graph or chart:
Different types of graphs and charts are used to represent different types of data.
Common types of graphs and charts include bar charts, line charts, scatter plots, pie charts, and histograms.
Knowing the type of graph or chart will help you understand what information is being presented.
Look at the axis labels:
The \( x \)-axis and \( y \)-axis labels provide information about the units of measurement and the range of values represented on the graph or chart.
Understanding the axis labels is essential to interpreting the data correctly.
Read the legend or key:
If the graph or chart includes a legend or key, read it carefully to understand what each color, symbol, or line represents.
Identify any trends or patterns:
Look for any trends or patterns in the data.
For example, are there any obvious increases or decreases in the data over time? Are there any clusters or outliers in a scatter plot?
Look for any relationships:
If the graph or chart includes two variables, look for any relationships between them.
For example, does an increase in one variable correspond to an increase or decrease in the other variable?
Draw conclusions:
Once you have analyzed the graph or chart, draw conclusions about the data.
What insights can you gain from the information presented? What implications does the data have?
It’s important to remember that statistical diagrams are just one tool for analyzing and understanding data. They are most useful when combined with other statistical methods and when used in the context of a larger research question or problem.
Comparing:
Comparing statistical diagrams involves analyzing and contrasting the information presented in
two or more graphs or charts.
Comparing statistical diagrams is a common practice in data analysis and can be useful for identifying trends, patterns, and relationships in the data.
When comparing statistical diagrams, there are several things to keep in mind:
Types of graphs:
The graphs being compared should be of the same type or at least similar enough to allow for meaningful comparisons.
For example, comparing a histogram to a scatter plot would not be appropriate.
Axis scales:
Ensure that the scales on the \( x \)-axis and \( y \)-axis are the same or similar between the graphs being compared.
If the scales are not the same, the graphs may be misleading and could lead to inaccurate conclusions.
Data range:
Make sure that the range of data represented on each graph is comparable.
If one graph represents a smaller range of data than another, it could skew the comparison.
Identifying patterns and trends:
Look for similarities and differences in the patterns and trends presented in the graphs.
Do they show similar or contrasting trends? Are there any patterns or trends that are unique to one graph?
Drawing conclusions:
Based on the analysis of the graphs, draw conclusions about the data being presented.
Are there any insights or implications that can be gained from the comparison?
Test yourself
Question 1:
The table shows how children in Ivan’s class travel to school.
Ivan wants to draw a pie chart to show this information.
Find the sector angle for children who walk to school.
[2]
Question 2:
\( 40 \) people were asked how many times they visited the cinema in one month.
The table shows the results.
Omar wants to show the information from the table in a pie chart.
Calculate the sector angle for the people who visited the cinema \( 5 \) times.
[2]
Question 3:
The number of people swimming in a pool is recorded each day for \( 12 \) days.
Complete the stem and leaf diagram.
[2]
Find the median number of swimmers.
[1]
Question 4:
The table gives some information about the birds Paula sees in her garden one day.
Complete the accurate pie chart.
[3]
Question 5:
Chloe recorded the test marks of \( 20 \) students.
Show this information in an ordered stem and leaf diagram.
[3]
One of these students is going to be chosen at random.
Find the probability that this student has a test mark less than \( 28 \).
[2]