6.1 Statistical Analysis Flashcards
Quantitative
measured using a naturally occurring numerical scale
Qualitative
deals with descriptions
Standard deviation
a measure of the variability or dispersion of a data set
What are the statistics of percentages of standard deviation?
A normal distribution approximately 68% of the values fall within plus or minus one and approximately 95% for two standard deviation
What does a low sd mean?
data points tend to be close to the mean, the data is more precise and reliable
What does a high sd mean?
data is more “spread out”, less precise and reliable
What do overlaps in error bars mean?
No overlap=not a significant difference
Large overlap=there is a significant difference
Coefficient of variation
it is the ratio of the standard deviation to the mean and expressed as a percentage
Why might it be useful to use coefficient of variation instead of standard deviation?
If they have different units e.g. kg and seconds
T-test
it is a statistical test that helps us determine the significance of the difference between the means of two sets of data
Correlation
a trend in the results used to define the extent of a relationship between two variables (correlation DOESN’T mean causation)
Pearson’s r
measures the strength of the linear relationship between two variables
Coefficient of determination
it is how much variability of one factor can be caused by its relationship to another related factor
