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Books
Probability and Statistics in Engineeringand Management Science,
W. Hines
D.C. Montgomery
Wiley Publication
Course organization
1. Definations
2. Data description and definitions
3. Random sample and sampling distributions
4. Point and Interval estimations
5. Statistical hypothesis testing
6. Nonparametric hypothesis testing
DefinitionsStatistics
A collection of methods for planningexperiments, obtaining data, and thenorginizing, summarizing, presenting, analyzing, interpreting, and drawingconclusions based on the data
Data
Observations ( such as measurements, survey responses) that have been collected andrecorded.
DefinitionsPopulation
The complete collection of all elements (scores, people, measurements, and so on) to be studied. The collection is complete in the sense that it includes all subjects to be studied.
DefinitionsSample data must be collected in an apropriate way such as through a process of random selection.
Sample
A sub-collection or sub-set of population
DefinitionsQualitative data (categorical orattribute data)
Representing numbers or countabledata
Example: the number of defectiveunits
Discrete data
Quantitative data
representing measurement values
Example: the weights of packedbiscuits
Continuous data
DefinitionsRandom sample
Member of population are selectedin such a way that each individualmember has an equal chance of being selected
Simple Random sample (sample size n)
Subjects selected in such a way everyposible sample of the same sample size n has the same chance of being chosen
DefinitionsSampling
Selecting n units (sample size n) from population and then estimate thapopulation parameters from sample
Why we need the sampling do not reach to the population
reaching to the population can be costly
reaching to the population can take more time
measurement technique may be destructive and sample can’t use again
Methods of SamplingSimple Random sample (sample size n)
Subjects selected in such a way every posible sample of the same sample size n has the same chance of being chosen
Systematic sampling
Select same starting point and then select every k th element in thepopulation
Convenience sampling
Use result that are easy to get
Methods of SamplingStratified sampling
Subdivide the population into at least two different subgroups that share thesame characteristics, then draw a sample from each subgroups (stratum)
Cluster sampling
Dive the population into sections (or clusters), then randomly select samplefrom each clusters
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