statistics with computer analysis statistics math 1551 instructor robert barber
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Statistics with Computer Statistics with Computer AnalysisAnalysis
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Instructor Robert Barber
Use of Course InformationUse of Course Information
This course material is intended solely for the use by the instructor and students enrolled in an approved course. This material is only for educational purposes and is not to be packaged and sold. Use of this material by others is not permitted without the express approval of this instructor.
Credit is given to the authors of McClave and Sincich for their text, A First Course in Statistics (Ninth Edition), and Brase and Brase for their text, Understandable Statistics (Eighth Edition), and related materials upon which much of this presentation was based.Statistics Math 155 2
Important Course Important Course InformationInformationAll course information is on the
MyClasses website, which can be reached at myclasses.salisbury.edu
The website includes, syllabus, class policies, tentative class schedule, grades, and homework assignments
The website also includes my office hours and office phone number and e-mail address.
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Major Course Major Course RequirementsRequirementsThe statistical software package
Mini-Tab will be used. Buy it for home use or find it on the computers in the school computer labs.
A graphing calculator will be used for in-class tests, quizzes and exercises. The TI-83 or TI-84 is preferred because of extensive text reference. Statistics Math 155 4
Keys to successKeys to success
Commit to excellenceAttend and participate in classSeek help from me during my office
hoursTake advantage of free tutoring
servicesDo your homework. Work other
problemsAsk questions about areas you do not
understand. E-mail me at [email protected]
Read the textbookGet in a study group. Invite me
sometimes.
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Course ObjectiveCourse Objective
To introduce the concepts of statistical inference by way of both non-parametric and classical parametric methods.
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What is statistics?What is statistics?
Statistics is the science of collecting, classifying, organizing, describing, summarizing, analyzing, and interpreting numerical information for the purpose of making informed inferences about an unknown population(s) and to assist in the decision-making process regarding the population(s) of interest.
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Course PlanCourse Plan
Step 1- Give you an understanding of the process of statistical analysis.
Step 2- Relate the chapters in the textbook to the process and provide you with an understanding of why we are discussing each topic area.
Step 3- Begin in chapter one and follow the sequence, i.e., the process, as we navigate through the text.
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Why do we do Statistics?Why do we do Statistics?A business wants to know if there
is a market for a new product they developed.
The government wants to know if it is safe to approve a new drug.
You want to know which investment has the least risk.
We want to predict the weather.Someone makes a claim and we
want to test to see if the claim is believable.
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Statistics usually involves Statistics usually involves drawing a sample from a drawing a sample from a large population, analyzing large population, analyzing the sample, and then the sample, and then drawing inferences about drawing inferences about the overall population. the overall population.
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Reasons for sampling!Reasons for sampling!
We cannot afford to measure the whole population.
We may not be able to find the whole population even if we could measure it.
We may not have the time to measure it all.
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Chapter 1Chapter 1Statistics,Data, and Statistics,Data, and Statistical ThinkingStatistical ThinkingWhat is the process for doing statistical
analysis?What are the different types of data?How is data collected?What is the difference between a
population and a sample ?What is the difference between
descriptive and inferential data?Why is probability theory involved?
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STATISTICAL ANALYSIS PROCESS
Population
SampleDescriptive
Statistics
Probability
Inferential Statistics
Parametric Nonparametric
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STATISTICAL ANALYSIS PROCESS(Interfaces)
Population
SampleDescriptive
Statistics
Probability
Inferential statistics
Parametric Nonparametric
data
statistics
test results
confidence intervals
Reliability
Measures
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STATISTICAL ANALYSIS PROCESS(Chapters)
Population
SampleDescriptive
Statistics
Probability
Inferential Statistics
Parametric Nonparametric
Chapter 1
Chapter 2
Chapters 3&4
Chapters 5,6&7
Important DefinitionsImportant Definitions
Population- set of individuals, items, units of interest.
Sample- a subset of individuals, items, units drawn from the population.
Representative sample- a sample that fairly represents the diversity of the population and obtained through random sampling
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Definitions(continued)Definitions(continued)Experimental unit- the object in
the population about which data is collected.
Variable- a characteristic or property of the experimental unit
Important DefinitionsImportant Definitions(continued)(continued)
Descriptive Statistics- the processes of :◦ using numerical and graphical
methods to look for patterns in the collected data.
◦ determining summary measures which describe the data set for use in subsequent analysis.
◦ presenting data in a convenient understandable form.
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Important DefinitionsImportant Definitions(continued)(continued)Inferential statistics- the processes
used to make estimates, predictions, draw conclusions, or other generalizations about an unknown population(s) based on an analysis of the collected sample data.
Statistical Inference- the estimate, prediction, conclusion, or other generalization made about a population(s).
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Food for thought!Food for thought!
How much evidence is required to either accept or
reject the claim of another?
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What is it that we What is it that we measure?measure?A characteristic of interest about
each individual or object we measure.◦e.g., Height, color, GPA, temperature
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Types Of DataTypes Of Data
Data- the information collected or measured for each member of the sample.◦Qualitative data- information that
cannot be found on a numeric scale, e.g., colors.
◦Quantitative data- information that can be found on a numeric scale, e.g., heights.
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Measurement ScalesMeasurement Scales(Levels of Measurement)(Levels of Measurement)Levels of Data Measurement
◦Nominal- Categorical data. Data such as names, places, things. Mathematical operations are meaningless.
◦Ordinal- Information that has a logical sequence or order. Data such as class rank, consumer opinions. Mathematical operations are meaningless.
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Measurement ScalesMeasurement Scales(Levels of Measurement)(Levels of Measurement)(continued)(continued)
◦Interval- numeric measured data where the interval between measurements is meaningful but division is not. e.g., Temperature. Data with no true zero.
◦Ratio- measured numeric data where interval and ratios are meaningful. e.g., height. Data with a true zero.
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How is data obtained?How is data obtained?Published documents, such as
journals.Surveys, such as consumer
questionnaires.Designed Experiments, such as
tests on new medicines.Observational studies, such as
observing and recording migration habits of birds.
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Difference Between Difference Between ExperimentExperimentand Observationand ObservationExperiment- some treatment is
imposed on some or all of the individuals.◦Some patients are given a drug while
others are given a placebo.
Observation- no treatment is imposed.◦Count the number of different colored
cars in a parking lot. Statistics Math 155 27
Another Form of Data Another Form of Data CollectionCollectionSimulation- a model or facimile of
a real world phenomenon.Done when it is impractical to
measure the real world.◦The effects of a nuclear blast.
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Samples are reliable if:Samples are reliable if:
They are representative of the underlying population from which they are drawn, i.e., there are no selection bias errors.
Measurement errors are minimizedCare is taken when recording
sample data
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How can you get a random How can you get a random sample?sample?Use a Random Number Table.
Use a Random Number Generator in MiniTab and the TI83/84.
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Different Sampling Different Sampling TechniquesTechniquesStratified- items of interest are put
into layers, e.g., seniors, juniors, etc.
Systematic- every nth item is measured.
Cluster- clusters a randomly picked and every item in a cluster is measured.
Convenience- individuals are measured as they come along.
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Inferences are made in the Inferences are made in the context of a measure of context of a measure of reliabilityreliabilityA measure of reliability is a
statement about the degree of certainty or uncertainty associated with a statistical inference.
Probability theory is a fundamental part of statistical analysis and the development of measures of reliability.
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