Starter QUIZ Take scrap paper from little table Ask each student in this class if they are taking a foreign language class, record their answers and answer the following questions. 1) Name the population. 2) Name the sample. 3) Give a piece of data. 4) Is your data a parameter or a statistic? 5) Give an inferential statistic about the info you collected. HAVE HW OUT TO BE CHECKED.

HOMEWORK

Section 1.2 Objectives qualitative or quantitative Distinguish between qualitative data and quantitative data Classify data with respect to the four levels of measurement Larson/Farber 4th ed.

Types of Data Qualitative Data Consists of attributes, labels, or nonnumerical entries. Major Place of birth Eye color Larson/Farber 4th ed.

Types of Data Quantitative data Numerical measurements or counts. Age Weight of a letter Temperature Larson/Farber 4th ed.

Types of Data Data sets can consist of two types of data: qualitative data and quantitative data. Data Qualitative Data Quantitative Data Consists of attributes, labels, or nonnumerical entries. Consists of numerical measurements or counts.

Example: Classifying Data by Type The base prices of several vehicles are shown in the table. Which data are qualitative data and which are quantitative data? (Source Ford Motor Company) Larson/Farber 4th ed.

Solution: Classifying Data by Type Qualitative Data (Names of vehicle models are nonnumerical entries) Quantitative Data (Base prices of vehicles models are numerical entries) Larson/Farber 4th ed.

Levels of Measurement The level of measurement determines which statistical calculations are meaningful. The four levels of measurement are: nominal, ordinal, interval, and ratio. Nominal Lowest to highest Levels of Measurement Ordinal Interval Ratio

Nominal Level of Measurement Data at the nominal level of measurement are qualitative only. Nominal Calculated using names, labels, or qualities. No mathematical computations can be made at this level. Levels of Measurement Colors in the US flag Names of students in your class Textbooks you are using this semester

Ordinal Level of Measurement Data at the ordinal level of measurement are qualitative or quantitative. Levels of Measurement Ordinal Arranged in order, but differences between data entries are not meaningful. Class standings: freshman, sophomore, junior, senior Numbers on the back of each player’s shirt Top 50 songs played on the radio

Levels of Measurement Nominal level of measurement Qualitative data only Categorized using names, labels, or qualities No mathematical computations can be made Ordinal level of measurement Qualitative or quantitative data Data can be arranged in order Differences between data entries is not meaningful Larson/Farber 4th ed.

Interval Level of Measurement Data at the interval level of measurement are quantitative. A zero entry simply represents a position on a scale; the entry is not an inherent zero. Levels of Measurement Interval Arranged in order, the differences between data entries can be calculated. Temperatures Years on a timeline Atlanta Braves World Series victories

Levels of Measurement Interval level of measurement Quantitative data Data can ordered Differences between data entries is meaningful Zero represents a position on a scale (not an inherent zero – zero does not imply “none”)EXAMPLE 0° Larson/Farber 4th ed.

Ratio Level of Measurement Data at the ratio level of measurement are similar to the interval level, but a zero entry is meaningful. A ratio of two data values can be formed so one data value can be expressed as a ratio. Levels of Measurement Ratio Ages Grade point averages Weights

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

Example: Classifying Data by Level Two data sets are shown. Which data set consists of data at the nominal level? Which data set consists of data at the ordinal level? (Source: Nielsen Media Research) Larson/Farber 4th ed.

Solution: Classifying Data by Level Ordinal level (lists the rank of five TV programs. Data can be ordered. Difference between ranks is not meaningful.) Nominal level (lists the call letters of each network affiliate. Call letters are names of network affiliates.) Larson/Farber 4th ed.

Example: Classifying Data by Level Two data sets are shown. Which data set consists of data at the interval level? Which data set consists of data at the ratio level? (Source: Major League Baseball) Larson/Farber 4th ed.

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.) Larson/Farber 4th ed.

Summary of Levels of Measurement Determine if one data value is a multiple of another Subtract data values Arrange data in order Put data in categories Level of measurement Nominal Yes No No No Ordinal Yes Yes No No Interval Yes Yes Yes No Ratio Yes Yes Yes Yes

Section 1.2 Summary Distinguished between qualitative data and quantitative data Classified data with respect to the four levels of measurement Larson/Farber 4th ed.

Together Pg 13 1-18

HOMEWORK PAGE 13 19-30