Page 26 - Basic Statistics

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b. Ordered data : 3, 4, 4, 5, 5, 7, 8, 8, 9, 10, 10, 10

Med = the value of the data in the ((12+1) / 2)th observation

= the value of the data in the 6.5th observation

Med = X6 + 0.5 (X7 - X6)

= 7 + 0.5 (7-8) = 7.5

c. Mode

Mode is the most frequent events in an event. Thus the mode of a set of

data is the data value that has the greatest frequency or the most frequent.

Mode the data can not exist and can not be unique. If there are two modes of a

set of data, the so-called bimodal. If there are three modes called trimodal.

Worked Example 2.3 :

Find the mode of the following data

Data : a. 6, 4, 3, 5, 5, 6, 6, 6, 7, 9, 8
b. 5, 6, 3, 4, 7, 7, 8, 8, 9, 8, 7

Worked Solution :

a. The value of the data that most often arises is the value of 6, with 4

frequencies so that the mode of this data is 6, written Mod = 6.
b. The are two of the most frequent data values appear with the greatest

frequency, the value of 7 and a value of 8, both have frequency 3.

Bimodal of this data is 7 and 8.

Other measures of central location, but is more often used as a measure of
the spread are first quartile, third quartile 3, minimum value and maximum

value. Quartiles together with the minimum value and maximum value is often

termed a series five statistical or called robust statistical. Is robust because in

addition to the measures of central located, as well as the size of the spread.

~~* CHAPTER 2 NUMERICAL MEASURES TO SUMMARIZE DATA *~~