Describing Data Visually (ch 3)
Trend Line
descriptive tool that may help you find patterns in (X, Y) data
Pareto Chart
displays categorical data, with categories displayed in descending order of frequency, so that the most common categories appear first
Arithmetic Scale
distances on the Y-axis are proportional to the magnitude of the variable being displayed
Logarithmic Scale
equal distances represent equal ratios
Left-Skewed
histogram has a longer left tail, with most data values clustered on the right side
Right-Skewed
histogram has a longer right tail, with most data values clustered on the left side
Symmetric
neither tail is longer on a histogram
Pie Chart
only convey a general idea of the data
Pivot Table
provides interactive analysis of a data matrix
Line Chart
sed to display a time series, to spot trends, or to compare time periods
Scatter Plot
shows n pairs of observations as dots on an X-Y graph
Dot Plot
simple graphical display of n individual values of numerical data
Stacked Column Chart
the bar height is the sum of several subtotals
Stacked Dot Plot
used to compare two or more groups
Shape
Are the data values distributed symmetrically? Skewed? Sharply peaked? Flat? Bimodal?
Center
What are the units of measurement? Are the data integer or continuous? Any missing observations? Any concerns with accuracy or sampling methods?
Measurement
What are the units of measurement? Are the data integer or continuous? Any missing observations? Any concerns with accuracy or sampling methods?
Variability
What are the units of measurement? Are the data integer or continuous? Any missing observations? Any concerns with accuracy or sampling methods?
Histogram
a graphical representation of a frequency distribution
Sturges' Rule
a guideline proposed by statistician Herbert Sturges, every time we double the sample size, we should add one bin
Bar Chart
a horizontal display of data
Ogive
a line graph of the cumulative frequencies
Frequency Polygon
a line graph that connects the midpoints of the histogram intervals, plus extra intervals at the beginning and end so that the line will touch the X-axis
Frequency Distribution
a table formed by classifying n data values into k classes called bins
Stem-and-Leaf Plot
a tool of exploratory data analysis (EDA) that seeks to reveal essential data features in an intuitive way
Column Chart
a vertical display of data
Outlier
an extreme value that is far enough from the majority of the data that it probably arose from a different cause or is due to measurement error
