variables and type of data

VARIABLES AND VARIABLES AND TYPES OF DATATYPES OF DATA

(QUALITATIVE, QUANTITATIVE, DISCRETE AND CONTINOUS

VARIABLES)

Why do we have to study statistics?

To read and understand various statistical studies in related field.

To communicate and explain the results of study in related field using our own words.

To become better consumers and citizens.

Variable

O a characteristics of interest about each individual element of a population or sample

O Example : amount of time spent by one

student

Data O the set of values collected from

the variable from each of the elements that belong to sample

O Example : a value representing the

amount of time spent by one student in years, quarters. months

ExampleA statistics student is interested in finding out something about the average ringgit value of cars owned by the faculty members of our university. Each of the seven terms just describe can be identified in this situation.

1. VARIABLE: the “ringgit value” of each individual car

2. DATA: the set of values that correspond to the sample obtained (45,000; 55,000; 34,0000;…)

From the data collected, the type of data will be identified which classified to qualitative or quantitative, discrete or continuous variables………

Variables and types of Data

Qualitative Variable

Variables that can be placed into distinct categories, according to some characteristic or attribute

example gender (male or female).

Quantitative variables Numerical in nature and can

be ordered or ranked

Example: age is numerical and the

values can be ranked.

Discrete VariablesO A quantitative variable that

can assume a countable number of values.

O Can assume any values corresponding to isolated points along a line interval. That is, there is a gap between any two values.

O Clue countable

Continuous Variables

A quantitative variable that can assume an uncountable number of values.Can assume any value along a line interval, including every possible value between any two values.Clue measured

The grade point averages of five students are listed in the table. Which data are qualitative data and which are quantitative data

Example 1

Qualitative data

Quantitative data

Identify each of the following as an example of qualitative or quantitative variables.

Example 2

1.The breaking strength of a given type of string

2.The hair color of children auditioning for the musical Annie.

3.The number of stop signs in town of less than 500 people.

4.Whether or not a faucet is defective.

1. quantitative 2. qualitative

3. quantitative 4. qualitative

Answer 2

Example 3(from bluman text book)

Classify each variables as qualitative or quantitative

1. Marital status of nurse in a hospital2. Time it takes to run a marathon3. Weights of lobster in a tank in a restaurant4. Colors of automobiles in a shopping center parking lot5. Ounces of ice cream in a large milkshake6. Capacity of the NFL football stadiums7. Ages of people living in personal care home

Answer 3

1. Qualitative 2. Quantitative3. Quantitative 4. Qualitative 5. Quantitative 6. Quantitative 7. Quantitative

Example 4(from bluman text book)

Classify each variable as discrete or continuous

1. Number of pizzas sold by Pizza express2. Relative humidity levels in operating rooms at a local hospital3. Number of bananas in bunch at several local supermarket4. Lifetimes (in hours) of 15 iPod batteries5. Weights of the backpacks of first graders on a school bus6. Number of students each day who make appointments with a math tutor at a local college7. Blood pressure of runners in a marathon

Answer 4

1. Discrete 2. Continuous 3. Discrete 4. continuous5. Continuous 6. Discrete 7. Continuous

Video link

http://www.youtube.com/watch?v=Cc32-ebUnjM