Vocabulary
Set of values for a variable
Data
How much variability is there in a data set if the coefficient of variation is 2.1?
CoV ≤ 0.25: not much variability
0.25 < CoV < 0.50: some variability
0.50 < CoV ≤ 1: significant variability
CoV > 1: much variability
(From descriptive statistics lectures slides)
The value found by listing values in ascending order and taking the middle term. If there are two middle terms, take the average of these two.
Median
Find the mode of this data set: 4, 3, 5, 3, 6, 2
3
A _______ is a statement that can be matched with or evaluated against data (measurements). These claims are falsifiable.
Hypothesis
Measurable attribute of an object, entity, process or phenomenon
Variable
A low standard deviation indicates
Data values are close to the mean
The "A" in the IPAT equation represents
Affluence
Find the mean of this data set: 4, 3, 5, 3, 6, 2
3.83
A _____ is a well-substantiated explanation of some aspect of the world that is acquired through the scientific method and repeatedly tested and confirmed through observation and experimentation.
theory
Property of a claim or hypothesis such that it can be shown to be wrong or inaccurate (that is, contradicted by data).
Falsifiability
How much variability is there in a data set if the coefficient of variation is 0.4?
CoV ≤ 0.25: not much variability
0.25 < CoV < 0.50: some variability
0.50 < CoV ≤ 1: significant variability
CoV > 1: much variability
(From descriptive statistics lectures slides)
(Individual data value - mean) / standard deviation
Z-score
Find the median of this data set: 4, 3, 5, 3, 6, 2
3.5
_______ data is categorical and descriptive rather than numerical.
Qualitative
Data that can only take certain values, such as integers and whole numbers.
Example data set: 4, 3, 5, 3, 6, 2
Discrete data
If the mean is 27 and the median is 9, what can you predict about the data set?
Larger outliers pull the mean up. The median is resistant to outliers.
s2
variance
Find the standard deviation if the variance = 25.
5
Mathematical methods help to achieve _______.
Precision
A graph that shows the ongoing change in the concentration of carbon dioxide in Earth's atmosphere
Keeling Curve
If the Z-score for an individual value is 2.7, what does that tell us?
The value is 2.7 standard deviations away from the mean. This is pretty far away!
Standard deviation / mean
Coefficient of variation
Find the Z-score.
Individual data value: 5
Mean: 8
Median: 9
Standard deviation: 2
-1.5
________ is the process of taking a count and dividing it by something else (usually the first number in a data set) in order to make a number more comparable
Normalization