20
Feb
Interquartile Range Formula Statistics. For a sample of observations we define q1 to be the order statistic below which 25 of the data lies. In descriptive statistics the interquartile range tells you the spread of the middle half of your distribution. The range from Q 1 to Q 3 is the interquartile range IQR. Interquartile Range Q 3-Q 1.
The IQR for the test scores data set is Q3 Q1 or 89 68 21 which is fairly large seeing as how test scores only go from 0 to 100. Interquartile Range Quartile 3 Quartile 1 After calculating quartiles its rather easy to calculate an interquartile range. The interquartile range can be found by subtracting the first quartile value q1 from the third quartile value q3. Formula of Interquartile Range. Where IQR Interquartile range. Q3 3n1 th 4 th term.
Q1 1 st quartile.
With an Even Sample Size. The formula for calculating the interquartile range takes the third quartile value and subtracts the first quartile value. The formula for interquartile IQR is given by the difference between the upper or highest quartile third quartile and lower or lowest quartile first quartile. Q3 3n1 th 4 th term. Q1 is the middle value in the first half of the rank-ordered data set. For the sample n10 the median diastolic blood pressure is 71 50 of the values are above 71 and 50 are below.