Is an interquartile range different to a normal range?

Yes, the normal range is the difference from the highest to the lowest value.

The interquartile range is the difference from the upper quartile (75%) to the lower quartile (25%)

Hi, both can be used to find out the spread of values in a dataset. A normal range refers to a spread of numbers where the smallest number can be subtracted from the biggest number to find the middle half of the range. In comparison, an interquartile range refers to calculating the middle half of the range using the 25% and 75% percentiles in the dataset. The main difference in these methods is the fact that the interquartile range is not affected by outliers whereas the normal range is.

The interquartile range is the difference between the lowest and highest value in the middle 50% of the values (lower quartile and upper quartile) in a dataset. The range is the difference between the lowest and highest value in the whole data set.

Yes. The range is the difference between the biggest and smallest number in the list. The interquartile range uses quarters (hence the word quartiles). Find the numbers that are at the 1/4 and the 3/4 position of the list. Then find the difference between these. The interquartile range is useful especially when the data has outliers.

Yes, the interquartile range is the range between the number of the lower quartile and the number of the upper quartile. The normal range is the range between the lowest number and the highest number.

They are very similar but slightly different:

Range: The difference between the largest and smallest values in the set of numbers

Interquartile range [IQR]: the difference between the upper and lower quartile, where the four quartiles split the data into even quarters

Example:

1,1,3,4,6,7,8,9,10

Range = 10 - 1 = 9

IQR: Q3 [upper quartile] = 8.5, Q1 [lower quartile] = 2

IQR = 8.5-2 = 6.5

The Range looks at the spread of a data set, the biggest value subtract the smaller value whilst the interquartile range looks at the spread for the middle half of the data set. The upper quartile (Q3) subtract the lower quartile(Q1). Q3 is the 75th percentile for the data, and Q1 is the 25th percentile for the data

Yes, they are different; the normal range involves subtracting the smallest value in a data set from the largest value, whereas the interquartile range (IQR) involves taking the 25th percentile value on a box plot and subtracting it on the 75th percentile value.

Yes, the range is the distance from the highest value to the lowest value. The Inter-Quartile Range is quite literally just the range of the quartiles: the distance from the largest quartile to the smallest quartile, which is IQR=Q3-Q1.

Yes. The range is the difference between the highest value and the lowest value. However, the interquartile range is the difference between the upper quartile (75th percentile) and the lower quartile (25th percentile).

The range of a set of data is the difference in the highest value and the lowest value in that dataset.

The interquartile range is the difference in the lower and upper quartiles (data points that lie 1/4 and 3/4 into the dataset respectively).

The range is a measure of dispersion in the data, and is obtained by the maximum value by the minimum value. The interquartile range is more specialised and gives you an idea of the spread in the middle 50% of the data. This value is calculated by subtracting the lower quartile from the upper quartile. I hope this answers your question.

Yes the interquartile range is the difference between the upper quartile and the lower quartile whereas the range is the difference between the maximum number in the dataset and the minimum number.

The interquartile range is the difference between the 25th and 75th percentile (i.e 75th percentile value - 25th percentile value).

To get the 25th percentile value you need to:

1) line all the numbers in order from the smallest to the largest

2) add 1, then divide the total number of values by 4 (e.g if you have 19 numbers in total, first add 1, then you would divide 20 by 4 which is equals to 5)

3) find the 5th number from your number line starting from the smallest

To get the 75th percentile value you need to:

1) line all the numbers in order from the smallest to the largest again

2) add 1, then divide the total number of values by 4 (e.g if you have 19 numbers in total, you would divide 20 by 4 which is equals to 5), but then also times by 3 (e.g your answer 5 times by 3 is now 15)

3) find the 15th number from your number line starting from the smallest

You would then minus the 4th number from your 12th number

(p.s if the number your looking for is a decimal e.g the 25th percentile of 10 numbers, would be the 2.5th number on the number line, you would need to find the mean of the 2nd and 3rd number to get the 25th percentile)

e.g we have 15 number: 1,2,4,5,7,8,9,10,12,13,16,18,19,20,22

the interquartile range is the 25th percentile - the 75th percentile

the 25th percentile is (15+1 divided by 4, which is equal to 4), so we find the 4th number on the number line which is in order from smallest to largest, this is 5

the 75th percentile is (15+1 divided by 4, which is 4, times by 3, which is 12), so we find the 12th number on the line which is 18

The interquartile range is 18-5=13

The normal range is the largest number - the smallest number, this would be 22-1=21

Yes. The range of a dataset is the biggest number minus the smallest number. The interquartile range (think inner quarter so 25%, 75%) is the 75th percentile minus the 25th percentile. Try calculating it with a few different data sets and you should see why this might be used instead of the full range. Which is most useful will depend on the type of data being looked at.