Chapter 1 Introduction and Data Collection 数据收集与统计学简介 Business Statistics: A First Course Fifth Edition Chapter 1 Introduction and Data Collection 数据收集与统计学简介 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Learning Objectives（学习目标） In this chapter you learn: How Statistics is used in business 商业活动中如何使用统计学 The sources of data used in business 商业活动中使用数据的来源 The types of data used in business 商业活动中使用数据 的类型 The basics of Microsoft Excel Excel基础 The basics of Minitab 统计软件Minitab基础 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Why Learn Statistics? 学会统计学可以帮助你更好理解和使用无所不在的“数据（数字）”: Business memos（商业签单） Business research（商业研究） Technical reports（技术报告） Technical journals（技术学报） Newspaper articles（报纸文章） Magazine articles（杂志文章） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

What is statistics? A branch of mathematics taking and transforming numbers into useful information for decision makers（数学的一个分支——将繁杂的数据处理为对决策者有用的信息） Methods for processing & analyzing numbers（处理和分析数据的方法） Methods for helping reduce the uncertainty inherent in decision making（降低决策中的不确定性的方法） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Why Study Statistics? Decision Makers Use Statistics To： （通过使用统计方法，决策者可以：） Present and describe business data and information properly 正确的展示和描述商业数据的和信息（描述性统计） Draw conclusions about large groups of individuals or items, using information collected from subsets of the individuals or items. 利用收集到的个体或者商品的子集数据来推断有关更广范围内个体或者商品的结论（推断统计） Make reliable forecasts about a business activity 为商业活动提供可靠的预测（推断统计） Improve business processes 改善商业活动的过程 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Descriptive Statistics Inferential Statistics Types of Statistics Statistics The branch of mathematics that transforms data into useful information for decision makers. （数学的一个分支——将繁杂的数据处理为对决策者有用的信息） Descriptive Statistics 描述型统计 Collecting, summarizing, and describing data（收集、汇总和描述数据） Inferential Statistics 推断型统计 Drawing conclusions and/or making decisions concerning a population based only on sample data（利用样本信息来推断有关于总体的结论） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Descriptive Statistics Collect data（数据收集） e.g., Survey（调查） Present data（数据展示） e.g., Tables and graphs 分析图表 Characterize data（刻画数据的特征） e.g., Sample mean = （样本均值） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Inferential Statistics Estimation（估计） e.g., Estimate the population mean weight using the sample mean weight（样本均值估计总体均值） Hypothesis testing（假设检验） e.g., Test the claim that the population mean weight is 120 pounds（检验：总体的平均体重=120磅） Drawing conclusions about a large group of individuals based on a subset of the large group. Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Basic Vocabulary of Statistics VARIABLE（变量） A variable is a characteristic of an item or individual. 商品或者个体的某个属性叫做变量 DATA（数据） Data are the different values associated with a variable. 变量的不同取值形成数据 OPERATIONAL DEFINITIONS Data values are meaningless unless their variables have operational definitions, universally accepted meanings that are clear to all associated with an analysis. 数据值只有在其变量具有操作性定义（如何或用什么办法测量变量的描述）才有分析意义 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Basic Vocabulary of Statistics POPULATION（总体） A population consists of all the items or individuals about which you want to draw a conclusion.（分析目标对应所有个体的集合叫总体） SAMPLE（样本） A sample is the portion of a population selected for analysis. (总体中被选来作分析的部分叫样本) PARAMETER（参数） A parameter is a numerical measure that describes a characteristic of a population.（总体的数字特称为参数） STATISTIC（统计量） A statistic is a numerical measure that describes a characteristic of a sample.（样本的数字特征称为统计量） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Population vs. Sample Population Sample Measures used to describe the population are called parameters 描述总体特征的数字测度叫参数 Measures computed from sample data are called statistics 通过样本计算得到数字特征值叫做统计量 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Why Collect Data? A marketing research analyst needs to assess the effectiveness of a new television advertisement. 市场研究分析员需要对新电视广告的投入效果进行评价 A pharmaceutical manufacturer needs to determine whether a new drug is more effective than those currently in use. 药品生产者需要判断新药的效果是否优于正在使用的药 An operations manager wants to monitor a manufacturing process to find out whether the quality of the product being manufactured is conforming to company standards. 生产执行经理需要通过监控生产过程来保证产品质量符合公司标准 An auditor wants to review the financial transactions of a company in order to determine whether the company is in compliance with generally accepted accounting principles. 审计人员需要通过翻阅公司的金融交易记录来判断该公司是否符合一般公认的会计准则 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Sources of Data Primary Sources: The data collector is the one using the data for analysis（一手数据：数据的分析使用者是收据收集本人） Data from a political survey（政治调查数据：盖洛普GALLUP） Data collected from an experiment（试验数据的收集） Observed data（观察型数据） Secondary Sources: The person performing data analysis is not the data collector（二手数据） Analyzing census data（公用普查资料） Examining data from print journals or data published on the internet. 在杂志或者互联网公开发布的数据 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Sources of data fall into four categories Data distributed by an organization or an individual（个人或者机构发布的数据） A designed experiment（通过试验设计来收集） A survey（调查数据） An observational study（通过观察性研究来收集） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Types of Variables Categorical (qualitative) variables have values that can only be placed into categories, such as “yes” and “no.” 分类型（定性）变量的取值只是做分类作用 Numerical (quantitative) variables have values that represent quantities. 数值型（定量）变量取值有数量上的意义 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Types of Data Examples: Marital Status（婚姻状态） Political Party（党派） Eye Color（眼睛的颜色） (Defined categories) Examples: Number of Children（小孩个数） Defects per hour（每小时产生的不合格数） (Counted items) Examples: Weight（体重） Voltage（电压值） (Measured characteristics) Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Personal Computer Programs Used For Statistics Minitab A statistical package to perform statistical analysis Designed to perform analysis as accurately as possible 一种专门的统计分析软件，被设计来尽可能的实现精确分析 Microsoft Excel A multi-functional data analysis tool Can perform many functions but none as well as programs that are dedicated to a single function. 你懂的，微软Office组件中最强大的数据分析工具，几乎可实现任何数据分析功能，但操作都很繁琐 Both Minitab and Excel use worksheets to store data 相同点是两者都用工作表来储存数据 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Minitab & Microsoft Excel Terms When you use Minitab or Microsoft Excel, you place the data you have collected in worksheets.（待分析的目标数据都放在工作表中） The intersections of the columns and rows of worksheets form boxes called cells. （工作表中行列交叉处为单元格） If you want to refer to a group of cells that forms a contiguous rectangular area, you can use a cell range. （可以选择性分析） Worksheets exist inside a workbook in Excel and inside a Project in Minitab. （工作表分别存在于Excel工作薄或者Minitab的项目中） Both worksheets and projects can contain both data, summaries, and charts. （ Excel工作薄或者Minitab的项目中可同时存储数据以及分析图表等信息。） Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

You are using programs properly if you can Understand how to operate the program 学会操作软件本身 Understand the underlying statistical concepts 理解各操作背后的统计概念 Understand how to organize and present information 学会组织和展示分析的有效信息 Know how to review results for errors 学会识别错误的分析结果 Make secure and clearly named backups of your work 确保自己的工作成果得到安全、醒目的备份 Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.

Chapter Summary In this chapter, we have Reviewed why a manager needs to know statistics Introduced key definitions: Population vs. Sample Primary vs. Secondary data types Categorical vs. Numerical data Examined descriptive vs. inferential statistics Reviewed data types Discussed Minitab and Microsoft Excel terms Business Statistics: A First Course, 5e © 2009 Prentice-Hall, Inc.