One-Variable Statistics Flashcards
Descriptive Statistics:
A way to quickly summarise data within a set using just a few numbers.
Mean:
The average of a set calculated by adding all the values in the set and dividing by the number of values in the set
Outlier:
A value or values that are significantly higher or lower than the rest of the set that can skew the mean of a set
Median:
The middle value in a data set
Mode:
The value that appears most often in the set.
When a set has two modes it is called Bimodal.
When a set has more than two modes it is called Multimodal.
Standard Deviation:
A measurement of the amount of variation from the mean in a data set
Five number summary:
The minimum, first quartile, median, third quartile and maximum of a data set.
Each quartile represents 25% of the data within a set.
The first and third quartile can be identified by finding the median of the lower and upper halves of the data set.
Range:
The distance between the maximum and minimum
Interquartile range:
Distance between the third and first quartiles
Boxplot:
A graph representing the five number summary. The boxed area represents the IQR with the median at the centre.
Frequency distribution:
A table that sorts data into equally-sized classes
Frequency:
The amount of data points that fall into each class
Cumulative frequency:
The running total of the frequencies
Relative frequency:
The frequency divided by the total number of data points
Cumulative relative frequency:
The running total of the relative frequencies
