INTRODUCTION TO STATISTICS LECTURE – 1 part 2 GE 608 Experimental Methods and Analysis Oct 18, 2015 Muharrum 13, 1437

MEASUREMENT Measurement may be defined as the assignment of numbers to objects (شيء) or events (أحداث ) according to a set of rules. 3

Levels of Measurement 1.Nominal (بالإ سم فقط ) level of measurement 2.Ordinal (ترتيبي ) level of measurement 3.Interval (الفاصلة ) level of measurement 4.Ratio (نسبة ) level of measurement 4

Levels of Measurement 1. Nominal (بالإ سم فقط ) level of measurement Qualitative data only Categorized using names, labels, or qualities No mathematical computations can be made 2. Ordinal (ترتيبي ) level of measurement Qualitative or quantitative data Data can be arranged in order Differences between data entries is not meaningful 5

Example: Classifying Data by Level Two data sets are shown. Which data set consists of data at the nominal (بالإ سم فقط ) level? Which data set consists of data at the ordinal (ترتيبي ) level? (Source: Nielsen Media Research) 6

Solution: Classifying Data by Level Ordinal (ترتيبي ) level (lists the ranks of five TV programs. Data can be ordered. Difference between ranks is not meaningful.) Nominal (بالإ سم فقط ) level 7

MEASUREMENT SCALES Nominal Scale ( بالإ سم فقط ) : Contains only qualitative data. Data at this level are categorized using names, labels, or qualities. (e.g., gender, perception) 8

MEASUREMENT SCALES Ordinal Scale ( ترتيبي ) : data are qualitative or quantitative. Data on this scale can be arranged in order but difference between data entries are not meaningful. (e.g., Education, Income) 9

Levels of Measurement 3. Interval (الفاصلة ) level of measurement Quantitative data Data can be ordered Differences between data entries are meaningful 10 Zero represents a position on a scale (not an inherent zero – zero does not imply “none”) e.g. temperature

Levels of Measurement 4. Ratio (نسبة ) level of measurement Similar to interval level Zero entry is an inherent zero (implies “none”) 11 A ratio of two data values can be formed One data value can be meaningfully expressed as a multiple of another

Example: Classifying Data by Level Two data sets are shown. Which data set consists of data at the interval level (الفاصلة ) ? Which data set consists of data at the ratio level (نسبة ) ? (Source: Major League Baseball) 12

Solution: Classifying Data by Level Interval level (Quantitative data. Can find a difference between two dates, but a ratio does not make sense.) Ratio level (Can find differences and write ratios.) 13

Summary of Four Levels of Measurement Level of Measurement Put data in categorie s Arrange data in order Subtract data values Determine if one data value is a multiple of another 1. Nominal (بالإ سم فقط ) YesNo 2. Ordinal (ترتيبي ) Yes No 3. Interval (الفاصلة ) Yes No 4. Ratio (نسبة ) Yes 14 For example: Names of TV channels: CNN, BBC

Summary of Four Levels of Measurement Level of Measurement Put data in categorie s Arrange data in order Subtract data values Determine if one data value is a multiple of another 1. Nominal (بالإ سم فقط ) YesNo 2. Ordinal (ترتيبي ) Yes No 3. Interval (الفاصلة ) Yes No 4. Ratio (نسبة ) Yes 15 For example: Top 3 TV programs: 1. Arab Idol, 2. AlJazeera News 3. Arab News

Summary of Four Levels of Measurement Level of Measurement Put data in categorie s Arrange data in order Subtract data values Determine if one data value is a multiple of another 1. Nominal (بالإ سم فقط ) YesNo 2. Ordinal (ترتيبي ) Yes No 3. Interval (الفاصلة ) Yes No 4. Ratio (نسبة ) Yes 16 For Example: Temperature

Summary of Four Levels of Measurement Level of Measurement Put data in categorie s Arrange data in order Subtract data values Determine if one data value is a multiple of another 1. Nominal (بالإ سم فقط ) YesNo 2. Ordinal (ترتيبي ) Yes No 3. Interval (الفاصلة ) Yes No 4. Ratio (نسبة ) Yes 17 For Example: Goals scored by different football teams

Summary of Four Levels of Measurement Level of Measurement Put data in categorie s Arrange data in order Subtract data values Determine if one data value is a multiple of another 1. Nominal (بالإ سم فقط ) YesNo 2. Ordinal (ترتيبي ) Yes No 3. Interval (الفاصلة ) Yes No 4. Ratio (نسبة ) Yes 18

Lecture-1 Summary Introduction to Statistics  Definitions Statistics, Data  Data sets Population, Sample, Parameters, Statistic  Branches of statistics Descriptive, Inferential Data classification  Types of data Qualitative, Quantitative 19

Lect 2 - Summary Data classification  Distinguished between qualitative data and quantitative data  Classified data with respect to the four levels of measurement: Nominal Ordinal Interval Ratio 20