Continuous Uniform Distribution

 

The continuous uniform distribution is the probability distribution of random number selection from the continuous interval between a and b. Its density function is defined by the following. Here is a graph of the continuous uniform distribution with a = 1, b = 3.

Formula

 

f(x) =

{1/(ba),0,when axbwhen x<a or x>b{1/(b−a),when a≤x≤b0,when x<a or x>b

Example

 

Problem Statement:

 

Suppose you are leading a test and present an inquiry on the crowd of 20 contenders. The time permitted to answer the inquiry is 30 seconds. What number of persons is prone to react inside of 5 seconds? (Regularly, the contenders are required to click a catch of the right decision and the champ is picked on the premise of first snap).

Solution:

 

Step 1: The interval of the probability distribution in seconds is [0, 30].

 The probability density is = 1/30-0=1/30. 

Step 2: The requirement is how many will respond in 5 seconds. That is, the sub interval of the successful event is [0, 5]. Now the probability P (x < 5) is the proportion of the widths of these two interval.

 5/30=1/6. 

Subsequent to there are 20 contenders, the quantity of contenders prone to react in 5 seconds is (1/6) (20) =3.

Cumulative Frequency

 

Cumulative frequency is defined as a running total of frequencies. The frequency of an element in a set refers to how many of that element there are in the set. Cumulative frequency can also defined as the sum of all previous frequencies up to the current point.

Example

Problem Statement:

The set of data below shows the ages of participants in a certain winter camp. Draw a cumulative frequency table for the data.

Age (years)

Frequency

10

3

11

18

12

13

13

12

14

7

15

27

Solution:

The cumulative frequency at a certain point is found by adding the frequency at the present point to the cumulative frequency of the previous point. The cumulative frequency for the first data point is the same as its frequency since there is no cumulative frequency before it.

Age (years)

Frequency

Cumulative Frequency

10

3

3

11

18

3 + 18 = 21

12

13

21 + 13 = 34

13

12

34 + 12 = 46

14

7

46 + 7 = 53

15

27

53 + 27 = 80