Environmental Data Analysis BC ENV 3017
Data summaries
Basic graphical representations of data as used in the ozone lab
There are different ways how to plot data

time series  entire time period vs. just the hours

bar graph vs. line plot (example: precipitation)

cyclicity, period

make the graph long, focus on a few days of data at the time

histograms

bins, frequency (array formula!), radar diagram

example: income in US

scatter plots
Descriptive statistics (qualitative, we will discuss the details later)

count

average (arithmetic mean)

the mean is the sum of a set of numbers divided by how many there are.

median

the median is the number in the middle of a set of numbers; that is, half
the numbers have values that are greater than the median, and half have
values that are less.

mode

the mode is the most frequently occurring, or repetitive, value in
an array or range of data.

minimum

maximum

range

standard deviation

the standard deviation is a measure of how widely values are dispersed
from the average value (the mean).

variance

another measure of the spread of the data.

kurtosis

kurtosis characterizes the relative peakedness or flatness of a distribution
compared with the normal distribution. Positive kurtosis indicates a relatively
peaked distribution. Negative kurtosis indicates a relatively flat distribution.

skewness

skewness characterizes the degree of asymmetry of a distribution around
its mean. Positive skewness indicates a distribution with an asymmetric
tail extending toward more positive values. Negative skewness indicates
a distribution with an asymmetric tail extending toward more negative values.