2: Tabular and Graphical Methods Flashcards
What is a frequency distribution for qualitative data?
How can this be made into a relative frequency distribution?
A table to show how frequent different events occurred.
This can be replaced with percentages to make a relative frequency distribution.
What are good ways to display qualitative data?
Pie charts and bar charts
How are classes useful in presenting quantitative data?
Continuous data can be put into classes to show frequency within set ranges to make the data easier to present.
What are good ways of displaying frequency distributions for quantitative data?
Histograms or polygons.
Histogram is similar to a bar chart.
Polygon plots points and draws a line to reflect the shape of the curve.
What is the difference between a histogram and a bar chart?
A histogram bar width reflects a range and is used for quantitative data.
A bar chart is used for qualitative data to reflect different labels.
How do you describe the different skews on a histogram?
If the histogram is leaning to the left, it is positively skewed.
If it is leaning to the right, it is negatively skewed.
If it is symmetrical, is has symmetric distribution.
What is an Ogive diagram?
This is a polygon which plots the cumulative relative frequency of each upper limit of the classes.
What is a stem and leaf diagram?
A table to record all of the observations, ideal when there is 40 or less.
One column reflects the first digit, the second column reflects the tail digits.
This helps to display clusters.
What is a scatterplot?
A diagram to display whether two quantitative variables are related in a systematic way.
Linear / non-linear / no relationship.
Positive / negative
Strong / weak
