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Sta220 Section 1.1, 1.2, 1.3 Lesson Objective #1: Define statistics and statistical thinking Statistics: Statistics is the science of _______________, _______________, _______________, and _______________ information to draw _____________ or _____________ _____________. In addition, statistics is about providing a measure of _____________ in any conclusions. Data: Data describe __________________ of an individual. Data are used to draw a conclusion or make a decision. One goal of statistics is to describe and understand sources of __________________. Lesson Objective # 2: Explain the Types of Statistics Applications Statistic and Parameter: __________________ statistics consist of organizing and summarizing data. Descriptive statistics describe data through numerical summaries, tables, and graphs. A _________________ is a numerical summary based on a sample. _________________ statistics uses methods that take results from a sample, extends them to the population, and measures the reliability of the result. A _______________ is a numerical summary of a population. Lesson Objective # 3: Fundamental Elements of Statistics Statistical methods are particularly useful for studying, analyzing, and learning about _____________ of _______________________. An __________________________________ is an object ( e.g., person, thing, transaction, or event) about which we collect data. Population and Sample: The ____________ group of individuals to be studied is called the population. An ______________ is a person or object that is a member of the population being studied. A _____________ is a subset of the population that is being studied. The _______________ is a characteristic or property of an individual experimental (or observational) unit in the population. Example: ______________ is a variable Male, female, and so on are __________ A statistical inference is an _______________, ______________, or __________________ about a ___________________ based on information _________________ in a _______________. A ____________________________is a statement (usually quantitative) about the degree of uncertainty associated with a statistical inference. The Process of Statistics: 1. _______________________ 2. _______________________ 3. _______________________ 4. _______________________ EXAMPLE Illustrating the Process of Statistics Many studies evaluate batterer treatment programs, but there are few experiments designed to compare batterer treatment programs to non-therapeutic treatments, such as community service. Researchers designed an experiment in which 376 male criminal court defendants who were accused of assaulting their intimate female partners were randomly assigned into either a treatment group or a control group. The subjects in the treatment group entered a 40-hour batterer treatment program while the subjects in the control group received 40 hours of community service. After 6 months, it was reported that 21% of the males in the control group had further battering incidents, while 10% of the males in the treatment group had further battering incidents. The researchers concluded that the treatment was effective in reducing repeat battering offenses. (Source: The Effects of a Group Batterer Treatment Program: A Randomized Experiment in Brooklyn by Bruce G. Taylor, et. al. Justice Quarterly, Vol. 18, No. 1, March 2001.) Step 1: Identify the research objective. Step 2: Collect the information needed to answer the question. Step 3: Organize and summarize the information. Step 4: Draw conclusions from the data. Example 1 According to Variety (Aug. 27, 2009), the average age of viewers of live television programs broadcast on CBS, NBC, and ABC is 51 years. Suppose a rival network (e.g. Fox) executive hypothesizes that the average age of Fox viewers is less than 51. To test her hypotheses, she samples 200 Fox viewers and determines the age of each. a. Describe the population. b. Describe the variable of interest. c. Describe the sample. d. Describe the inference. Example 2 “Cola Wars” is the popular term for intense competition between Coca-Cola and Pepsi displayed in their marketing campaigns, which have featured movie and television stars, rock videos, athletic endorsements, and claims of consumer preference based on taste tests. Suppose, as part of a Pepsi marketing campaign, 1,000 cola consumers are given a blind taste test (i.e., a taste test in which the two brand names are disguised). Each consumer is asked to state a preference for Brand A or brand B. a. Describe the population. b. Describe the variable of interest. c. Describe the sample. d. Describe the inference.