Answer to Question #242104 in Statistics and Probability for HAP

Question

Define sample, population, variable, stem-and-leaf with example.

Answer 1

First, we take an example to understand sample and proportion and then we define sample and population.

Henry is searching for IT jobs advertisements in Canada. One day, he notes 100 advertisements out of all advertisements. So, all IT jobs advertisements represent population while 100 advertisements represent the sample.

A population is an entire group that you want to work on.

A sample is the part of the population that you will collect data about.

Let's take another example to understand a variable.

Suppose, you toss a coin three times. So, X can be represented as a random variable that denotes the number of heads. X can take the values 0, 1, 2, or 3.

A variable is defined as an attribute that can be counted.

Now, we will understand stem and leaf plot with the help of an example.

A data is taken representing the age of 10 people (in years).

24, 25, 27, 27, 32, 35, 43, 43, 47, 51

Its stem and leaf plot is given as,

Stem Leaf

2 4 5 7 7

3 2 5

4 3 3 7

5 1

It is a plot where data is split into stem and leaf where leaf generally represents the last digit and stem represents the other digits. This way the "stem" groups the scores and each "leaf" indicates a score within that group.