Deviation vs, Standard Deviation
Deviation
Deviation is how far is individual data from its mean data.
Standard Deviation
Standard Deviation tell you dispersion of data in slightly different way. Standard Deviation indicate how data is spread in general or average dispersion of data.
Note:
Q: Why do we use standard deviation instead of deviation:
A: Deviation describes how far from the mean the individual datum is located, but it does not show whole data. Thus, if you add all deviations, your result equals to zero. This is why many statistical mathematician prefer to use standard deviation to analyze dispersion of data. Standard deviation present average dispersion of data and can be used for other statistic operation.
Q: Why do we use standard deviation instead of deviation:
A: Deviation describes how far from the mean the individual datum is located, but it does not show whole data. Thus, if you add all deviations, your result equals to zero. This is why many statistical mathematician prefer to use standard deviation to analyze dispersion of data. Standard deviation present average dispersion of data and can be used for other statistic operation.
Quartile Vs Percentile
Quartile
Quartiles divide a set of ordered data into four groups with equal numbers of values, just as the median divides data into two equally sized groups.
Interquartile: Q(3) ~ Q(1)
Interqurtile Range: Q(3) - Q(1)
Q: Where do we use the "Quartile"
A: Quartile also use for measure of spread data. Which data does belong to top 25 %?
Interquartile: Q(3) ~ Q(1)
Interqurtile Range: Q(3) - Q(1)
Q: Where do we use the "Quartile"
A: Quartile also use for measure of spread data. Which data does belong to top 25 %?
Percentile
It is same as quartile but it just uses 100 intervals.
Z-Score
You can look at Z-Score at different version or presenting data dispersion.