Quick Answer: What Does The First Quartile Represent?

What does q1 and q3 represent?

Q1 is the median (the middle) of the lower half of the data, and Q3 is the median (the middle) of the upper half of the data.

(3, 5, 7, 8, 9), | (11, 15, 16, 20, 21)..

What do quartiles tell us?

Quartiles tell us about the spread of a data set by breaking the data set into quarters, just like the median breaks it in half. For example, consider the marks of the 100 students below, which have been ordered from the lowest to the highest scores, and the quartiles highlighted in red.

What does q1 mean in a box plot?

Q1 – quartile 1, the median of the lower half of the data set. Q2 – quartile 2, the median of the entire data set. Q3 – quartile 3, the median of the upper half of the data set. IQR – interquartile range, the difference from Q3 to Q1.

What is the upper quartile range?

The upper quartile is the value of the middle of the second set, where 75% of the values are smaller than Q3 and 25% are larger.

What is the value of the upper quartile?

The smallest data value (the 0th percentile). The lower quartile (the 25th percentile, one-fourth of the way in from the smallest). The median (the 50th percentile, in the middle). The upper quartile (the 75th percentile, three-fourths of the way in from the smallest and one-fourth of the way in from the largest).

What does first quartile mean?

First quartile: the lowest 25% of numbers. Second quartile: between 25.1% and 50% (up to the median) Third quartile: 51% to 75% (above the median) Fourth quartile: the highest 25% of numbers.

What does upper quartile mean?

The upper quartile (sometimes called Q3) is the number dividing the third and fourth quartile. The upper quartile can also be thought of as the median of the upper half of the numbers. The upper quartile is also called the 75th percentile; it splits the lowest 75% of data from the highest 25%.

What is the value of the first quartile?

The first quartile, denoted by Q1 , is the median of the lower half of the data set. This means that about 25% of the numbers in the data set lie below Q1 and about 75% lie above Q1 . The third quartile, denoted by Q3 , is the median of the upper half of the data set.

What are quartiles used for in real life?

Quartiles are used to summarize a group of numbers. … All numerical summaries—like mean, median, and mode—give you a few numbers to summarize a large group of data, but what’s special about quartiles is that they split the data up into four equal-size groups.

Is the First Quartile the same as the 25th percentile?

Quartiles are special percentiles. The first quartile, Q1 , is the same as the 25 th percentile, and the third quartile, Q3 , is the same as the 75 th percentile. The median, M , is called both the second quartile and the 50 th percentile.

How are quartiles calculated?

Quartiles are the values that divide a list of numbers into quarters: Put the list of numbers in order. Then cut the list into four equal parts. The Quartiles are at the “cuts”…Box and Whisker PlotQuartile 1 (Q1) = (4+4)/2 = 4.Quartile 2 (Q2) = (10+11)/2 = 10.5.Quartile 3 (Q3) = (14+16)/2 = 15.

How do you find the top quartile?

How to Calculate QuartilesOrder your data set from lowest to highest values.Find the median. This is the second quartile Q2.At Q2 split the ordered data set into two halves.The lower quartile Q1 is the median of the lower half of the data.The upper quartile Q3 is the median of the upper half of the data.