Chapter 4 - Statistics Flashcards
The collection, tabulation, analysis, interpretation, and presentation of numerical data
Statistics
The Five Aspects of Statistics
Collection, tabulation, analysis, interpretation, and presentation
A collection of all possible elements, values, or items associated with a situation
Population
A subset of elements or measurements taken from a population
Sample
A sample will represent the population of it is
Random and Unbiased
Each item in the population had the same opportunity to be selected
Random Sample
Two types of statistics
Deductive (descriptive) and Inductive
Describes a population or complete group of data
Deductive (descriptive) Statistics
Deals with a limited amount of data or a representative sample of the population
Inductive Statistics
Two types of numerical data
Continuous and Discrete
Those quality characteristics that can be measured
Variables Data
Those quality characteristics that are observed to be either present or absent, conforming or non-conforming
Attribute Data
The measured value can take on any value within a range
Continuous Data
Will be countable using whole numbers
Discrete Data
Easily recognized because when viewed, it appears that the data are without order
Ungrouped Data
Grouped together on the basis of when the values were taken or observed
Grouped Data
Considered to be the difference between a value measured and the true value
Measurement Error
Shows the number of times each of the measured values occurred when the data were collected.
Frequency Diagram
Difference between histogram and frequency diagram
Data is grouped into cells on a histogram
Refers to the form that the values of the measurable characteristics take on when plotted or graphed.
Shape
Lack of symmetry
Skewness
Peakedness of the data
Kurtosis
Number of peaks in the data
Modes
Two halves are mirror images of each other
Symmetrical
A distribution with a high peak
Leptokurtic
A flatter curve
Platykurtic
If the distribution displays more than one peak
Multimodal
Distributions with two distinct peaks
Bimodal
Measures of central tendency
Averages, medians, modes
Measures of dispersion
Range and standard deviation
Shows the dispersion of the data within the distribution
Standard Deviation
The standard deviation of the population is sometimes known as
Root mean square deviation
A group of sample averages tends to be normally distributed; as sample size n increases, this tendency toward normality improves
Central limit theorem
The area under the curve can be determined if blank and blank are known
Mean and standard deviation
A technique that enables us to determine how well the subgroup average approximates the population mean
Confidence interval testing
Equal to one-half the precision
Greatest Possible Error (GPE)
When calculating, the final answer can be no more accurate than the blank
Incoming Data
In general, for a frequency distribution, the number of cells or groups should be between blank and blank
5 and 20
Whenever possible, the midpoint values should be blank blank so that they will be the same number of decimal places as the data values.
Odd Interval
A simple technique to determine the cell interval is called…
The Sturgis Rule
Blank blank are an extra decimal place or significant figure in accuracy than the observed values.
Boundary Values