Data Has Shape. Did you know? Data has Shape! Examples. My Data What do you think the shape of height data for this class looks like?

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2 Data Has Shape Did you know? Data has Shape! Examples My Data What do you think the shape of height data for this class looks like? Data From you Calculate your height in inches From the shape of the data what can we say? What does the middle height appear to be? What is the tallest height, shortest? Assume our class is representative of every class in the Wattis Building, what is the chance a random person next door is shorter than 74 inches (6 2 ) Who cares?

3 Data Has Shape What is the shape of Age in the United States right now? What did it look like in 1950? What will it look like in 40 years? Who cares? Age Distribution in US First main topic of course: Summarizing data both graphically and numerically. Second main topic of course: Probability and data comparison

4 Data and Information DATA is not information! Data (numbers) must be distilled to something meaningful Information Statistics is the science of transforming data into information to make decisions in the face of uncertainty

5 Data and Data Sets Data: The facts figures collected, summarized, analyzed, and interpreted The data collected in a particular study are called the data set.

6 Elements, Variables, Observations The elements are the entities on which data are collected A variable is a characteristic of interest for the elements The set of measurements collected for a particular element is called and observation The total number of data values in a complete data set is the number elements multiplied by the number of variables

7 Data, Data Sets, Elements, Variables, and Observations Element Names Company Variables Stock Annual Earn/ Exchange Sales($M) Share($) Dataram EnergySouth Keystone LandCare Psychemedics NQ N N NQ N Data Set

8 Elements, Variables, Observations Examples Insurance Example Affairs Example

9 Categorical vs. Quantitative Statistical Analysis used depends on which type of data we have. Categorical Data Uses labels or names to indentify attributes of each element Can be numeric or nonnumeric THOUGHT: What the underlying concept of interest Examples Amazon Bond Ratings Quantitative Data Numeric Values, indicate how much or how many. Always numeric

10 SCALES of Categorical and Quantitative data Categorical Data Nominal: Data for a variable is a name or label Example: Female, Male. ECON, FIN, ACCT. Can be Numeric Female = 1, Male = 0 Ordinal Conveys an order or rank. Example: Best Employers Quantitative Data Interval Scale Data Measured on a scale with equal distances between measurements No Absolute Zero Cannot be multiplied or divided meaningfully Example Degrees Fahrenheit, *2 Standardized Test Scores Ratio Scale Multiples can be compared Has an zero value that indicates that nothing exists there Example: Height, age, weight

11 Scales of Measurement Nominal Each value is a category Ordinal Order has meaning Interval Units of measurement Ratio True absolute zero

12 Identify the type: Quant or Categorical? Scale of Measurement? Height: Course Grade: Age: Football jersey number:

13 Scales of Measurement Data Categorical Quantitative Numeric Non-numeric Numeric Nominal Ordinal Nominal Ordinal Interval Ratio

Types of Data Sets Cross-Sectional Data: Collected at the same or approximately the same point in time Time series data: Collected over several time periods Cross-Sectional or Time Series?

14 Types of Data Sets Cross-Sectional Data: Collected at the same or approximately the same point in time Time series data: Collected over several time periods Cross-Sectional or Time Series? Number of building permits issued in June 2008 in each county in UT Number of building permits issued in Weber County, UT in each of last 36 months Number of Vehicles produced by auto manufactures in each year from Number of Vehicles produced by each auto manufacture in 07

15 Where to get Data? Secondary Sources You are looking at data someone else gathered Internal to your company Sales Reports Customer Profiles Inventory Levels Human Resources Information Outside Sources Census Bureau Where are there a lot of your target demographic? Areas with high education Bureau of Labor Statistics Hourly earnings Consumer Spending Primary Source The data you want, you go out and get. Set up a controlled experiment Send out a survey

16 Population Sample Census Real

BUSINESS DECISION MAKING. Topic 1 Introduction to Statistical Thinking and Business Decision Making Process; Data Collection and Presentation

BUSINESS DECISION MAKING. Topic 1 Introduction to Statistical Thinking and Business Decision Making Process; Data Collection and Presentation BUSINESS DECISION MAKING Topic 1 Introduction to Statistical Thinking and Business Decision Making Process; Data Collection and Presentation (Chap 1 The Nature of Probability and Statistics) (Chap 2 Frequency