Data Visualisation 1 Flashcards
What does a frequency table show?
Max and min responses
Mode (most common)
Identify outliers
Better for nominal and maybe ordinal data
Shows frequency of each variable
What does a frequency histogram show? When should a bar chart be used?
Numerical data, particularly interval data
Can see how often a response occurs in a dataset
See the shape of the distribution
Check for outliers
Use bar charts for ordinal or categorical frequency data
What is a frequency polygon?
Same information as frequency histogram but with a different look
What is a stem and leaf plot?
Data is broken down into either a stem or a leaf
stem: first digit/digits
leaf: last digit
Frequency for each stem and leaf variable
What does a box plot show?
Thin T shape at bottom and top of the box plot
This shows the minimum and maximum values
Outliers will fall outside of these T shapes
The box plot is split into the upper and lower hinge, through a median line at the middle of the box plot
Upper hinge: 75% of data
Lower hinge: 25% of data
The box plot shows the interquartile range
What are bar charts?
Categorical data, this is usually the x axis
The value for each category is usually the y axis
How are bar charts underlying averages shown? Why?
Plotting values on top of the bar charts
Reveals skewness and outliers
What does a line graph show?
Good for showing multiple trends
Good for showing trends over time
Time is usually the x axis
Amounts (e.g. percentages) are usually on the y axis
What do scatterplots show?
IV on the x axis
DV on the y axis
relationship between 2 quantitative variables
Each dot represents the level of DV for the different IV variables
Line of best fit
What does a pie chart show? What are the issues with this?
Differences in proportions are plotted into segments on a circle
Not always easy to read, sometimes people aren’t great at comparing circular segments visually
3D pie charts are even more difficult
