0
Can interquartile range be used for any data eg data below the lower quartile to find if the data is spread out or close together or must we use the lower quartile for data below the lower quartile?
Nghjing
No, interquartile range cannot be for any data. The lower quartile for data must be used below the lower quartile.
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
When should you throw out an outliers?
If the result is 1.5 x Inter Quartile Range (or more) above the Upper Quartile or 1.5 x Inter Quartile Range (or more) below the Lower Quartile.
What is the interquartile range of 54 and 65 and 66 and 68 and 73 and 75 and 75 and 78 and 82 and 82 and 87 and 97?
Since the set of data is arranged in numerical order, first we need to find the median (also called the second quartile), which separates the data into two equal groups, in our case there are 6 numbers in each group.54 65 66 68 73 75 | 75 78 82 82 87 97The first quartile (also called the lower quartile) is the middle value of numbers that are below the median, in our case is 67.54 65 66 | 68 73 75 | 75 78 82 82 87 97The third quartile (also called the upper quartile) is the middle value of numbers that are above the median, in our case is 82.54 65 66 | 68 73 75 | 75 78 82 | 82 87 97The interquartile range is the difference between the first and third quartiles, which is 15, (82 - 67).
What is the measure of quartile deviation?
A quartile deviation from some specified value, is the value or values such that a quarter of the observed values fall between these values and the specified value. Usually, but not always, the specified value is the median - the value such that have the observed values are below (and above) it. In that case, one quartile values will have a quarter of the values below it and the other will have a quarter of the values above it. The quartile deviations will be the differences between median and the two quartiles just calculated.
What is the above 25 percent quartile?
A range of data is split into 4 parts.0-25%25-50%50-75%75%-100%being above the 25% quartile means that 25% of all tested or categorized subjects are below the person in question.
What is the difference between quartile and median?
Median is found by the middle number in a sorted data set. So half of the numbers are greater than the median, and half are below the median. Quartile represents one fourth (or 25%) of the data set. They are usually labeled something like first, second, third, fourth (or sometimes top quartile, bottom quartile). For example, if 24 people are in a class and take a test. 24/4 = 6, so the top six grades would be in the top quartile (I don't remember if this is considered first or fourth). If you are in the top quartile, then you did better than at least 75% of the whole class. Since 24 is even, there is no 'middle number', so the arithmetic average of number 12 & 13 are taken to find the median.
Why do you multiply the interquartile range by 1.5 to find the outlier?
By definition a quarter of the observations are below the lower quartile and a quarter are above the upper quartile. In all, therefore, half the observations lie outside the interquartile range. Many of these will be more than the inter-quartile range (IQR) away from the median (or mean) and they cannot all be outliers. So you take a larger multiple (1.5 times) of the interquartile range as the boudary for outliers.
What is the difference between minimum and lower quartile?
Consider the data: 1, 2, 2, 3, 4, 4, 5, 7, 11, 13 , 19 (arranged in ascending order) Minimum: 1 Maximum: 19 Range = Maximum - Minimum = 19 - 1 = 18 Median = 4 (the middle value) 1st Quartile/Lower Quartile = 2 (the middle/median of the data below the median which is 4) 3rd Quartile/Upper Quartile = 11 (the middle/median of the data above the median which is 4) InterQuartile Range (IQR) = 3rd Quartile - 1st Quartile = 11 - 2 = 9
How do you determine outliers?
One definition of outlier is any data point more than 1.5 interquartile ranges (IQRs) below the first quartile or above the third quartile. Note: The IQR definition given here is widely used but is not the last word in determining whether a given number is an outlier. IQR = 10.5 â?? 3.5 = 7, so 1.5. IQR = 10.5.
When should you throw out an outliers?
If the result is 1.5 x Inter Quartile Range (or more) above the Upper Quartile or 1.5 x Inter Quartile Range (or more) below the Lower Quartile.
What is upper quartile?
The upper quartile is the 75% point of the variable. That is, it is the point with 75% of the observations below it and 25% of the observations above it. The upper quartile is the upper 25% of the data.
What is 1st Quartile in the box and whisker plot?
First quartile is the value below which 25 % (one-fourth) of the cases fall.
What does upper quartile mean?
The upper quartile is the 75% point of the variable. That is, it is the point with 75% of the observations below it and 25% of the observations above it.
What is the interquartile range of 54 and 65 and 66 and 68 and 73 and 75 and 75 and 78 and 82 and 82 and 87 and 97?
Since the set of data is arranged in numerical order, first we need to find the median (also called the second quartile), which separates the data into two equal groups, in our case there are 6 numbers in each group.54 65 66 68 73 75 | 75 78 82 82 87 97The first quartile (also called the lower quartile) is the middle value of numbers that are below the median, in our case is 67.54 65 66 | 68 73 75 | 75 78 82 82 87 97The third quartile (also called the upper quartile) is the middle value of numbers that are above the median, in our case is 82.54 65 66 | 68 73 75 | 75 78 82 | 82 87 97The interquartile range is the difference between the first and third quartiles, which is 15, (82 - 67).
What is the measure of quartile deviation?
A quartile deviation from some specified value, is the value or values such that a quarter of the observed values fall between these values and the specified value. Usually, but not always, the specified value is the median - the value such that have the observed values are below (and above) it. In that case, one quartile values will have a quarter of the values below it and the other will have a quarter of the values above it. The quartile deviations will be the differences between median and the two quartiles just calculated.
What is the above 25 percent quartile?
A range of data is split into 4 parts.0-25%25-50%50-75%75%-100%being above the 25% quartile means that 25% of all tested or categorized subjects are below the person in question.
What is the difference between quartile and median?
Median is found by the middle number in a sorted data set. So half of the numbers are greater than the median, and half are below the median. Quartile represents one fourth (or 25%) of the data set. They are usually labeled something like first, second, third, fourth (or sometimes top quartile, bottom quartile). For example, if 24 people are in a class and take a test. 24/4 = 6, so the top six grades would be in the top quartile (I don't remember if this is considered first or fourth). If you are in the top quartile, then you did better than at least 75% of the whole class. Since 24 is even, there is no 'middle number', so the arithmetic average of number 12 & 13 are taken to find the median.
What is the example of the lower quartile?
Lower Quartile (Q1): the number that divides the lower half of the data into two equal halves. For example, given this data: 25, 26, 27, 28, 29, 30, 40, 41, 42 The Median is 29. Now, you need to find the lower quartile. You want to look at all the data that is below the median, so: 25, 26, 27, 28, The median splits the data into two groups. Find the median of the lower group, which is 26.5 ((26+27)/2). The lower quartile is 26.5
