What is the function of tables and graphs?
helps summarize, interpret, and recognize characteristics in the data more easily than raw data
Centre
Middle of data set
Variation
how spread out the data is
Distribution
shape of the data
Outliers
data values far from the majority of the data
Time
changing characteristics of data over time
What type of graph best describes QUALITATIVE (categorical) data?
Bar Graphs
What type of graph best describes QUANTITATIVE (numerical) data?
scatter plots, histograms
Frequency distribution table
organizes raw data into categories and shows how often a category occurs
In a graph, what value is on the x axis?
the category; x values (quantitative) or labels (qualitative)
Ina graph, what value is on the y axis?
frequency
Histogram
-quantitative data (interval/ratio)
-bars TOUCH
-typically a bell-shaped curve
Bar graph
-qualitative data (nominal/ordinal)
-bars DO NOT TOUCH
Scatter plot
allows the researchers to see if there is a relationship between two quantitative variables
Positive linear relationship
of a scatter plot; as one variable increases, the other variable increases
Negative linear relationship
of a scatter plot; as one variable increases, the other variable decreases
No linear relationship
of a scatter plot; no pattern between variables
Which graph would be used to display the number of people who own different car brands?
Bar graph; qualitative data
Which graph would be used to display test scores?
histogram or scatter plot; quantitative data
True or false: bar graphs have bars that touch
False
True or false: histograms have bars that touch
True
