Graphical Descriptive Techniques I
by Fatin Nabilah Ayob
1. Descriptive Statistics
1.1. arranging, summarizing & presenting a set of data where useful information is produced
2. Describing Ordinal Data
2.1. No specific graphical techniques
2.2. Treat the data and techniques similar as nominal data
3. Graphical & Tubular Techniques for Nominal Data
3.1. Allowable calculation: Count frequency of each value of the variable
3.2. Frequency distribution
3.3. Relative frequency distribution
4. Describing Relationship Between Two Nominal Values
4.1. Only determine frequency of the values
4.2. Produce cross-classification table
4.3. Two variables are unrelated: Patterns of bar chart approximately the same
4.4. Some relationship exist: Some bar chart difer from others
5. Definitions
5.1. Variable= Characteristics of population & sample
5.2. Values of the variable= Range of possible values of a variable
6. Types of Data & Information
6.1. Interval Data (Quantitative/Numerical)
6.1.1. Real numbers. Eg: heights,weights,prices
6.2. Nominal Data (Qualitative/Categorical)
6.2.1. The values are categories. Eg: marital status. Single=1, Married=2, Divorce=3
6.3. Ordinal Data
6.3.1. Categorical in nature but their values have an order; a ranking. Eg: College Course Rating System: Poor=1, Fair=2, Very Good=3
7. Hirarchy of Data
7.1. Interval
7.1.1. Values are real numbers
7.1.2. All calculations are valid
7.1.3. Data may be treated as ordinal or nominal
7.2. Ordinal
7.2.1. Values must represent the ranked order of the data
7.2.2. Calculations based on an ordering process are valid.
7.2.3. Data may be treated as nominal but not as interval.
7.3. Nominal
7.3.1. Values are the arbitrary numbers that represent categories
7.3.2. Only calculations based on the frequencies of occurrence are valid.
7.3.3. Data may not be treated as ordinal or interval.