Chapter 2 Terms Flashcards
The collection of probabilities from the various outcomes possible in a situation
Event
Events that cannot occur simultaneously
Mutually exclusive events
Probability of an event occurring is 1 - the probability that the event will not occur
Compliment Rule
The symbol for the occurrence of something other than the event, A, in question
A^c
Symmetrical curve representing observed values relative to the mean
Standard Normal Distribution
Common term for Standard Normal Distribuiton
Bell-shaped Curve
Sum of the squared differences between values divided by the number of observations less 1 (n-1)
Variance
Square root of the variance represented by the symbol: theta
Standard Deviation
Central range within which 68.25% of values occur in a standard Normal distribution
+- 1 Standard Deviation
Central Range within which 95.44% of values occur in a standard Normal distribution
+- 2 Standard Deviation
Central Range within which 99.74% of values occur in a standard Normal Distribuion
+-3 Standard Deviation
Term defining increments of standard deviation located above or below the mean
z-score/z-value
Curve showing distribution values as non-symmetrical above/below the mean
Skewed Distribution
Curve in which the median is significantly different from the mean
Concentration of Values
Term referring to the distribution values above or below a given central portion of a distribuion
Tail
A value in a distribution that is substantially higher or lower than a defined central portion
Outlier
The highest and lowest values in a distribution expressed in the units of the research subjects
Range
Illustration comparing values of two variables that may be interrelated
Scatter plot or scatter diagram
Computer-calculated plot or graph estimating the relationship between two variables
Trend Line
Trend lines that model or forecast estimated values (past or future)using available data
Linear model
A formal mathematical proof of the Law of Large Numbers
Central Limits Theorem
Distribution of observed values in a sample often referred to as a “distribution”
Sampling Distribution
Estimated standard deviation likely among multiple samples
Sampling Error or Standard Error
Value of Sampling Error defining a range of variability relative to the selected confidence level
Margin of Error
Most commonly used confidence level with a range of +- 1.96 standard deviation of the mean
95% Confidence Level
At a 95% confidence level, Margin of Error defines the range of 95% of possible values
Common Margin of Error
Pair of statements used to focus a research objective on two mutually exclusive outcomes
Hypothesis
States the hope, fear, expectation or concern of the testing organization
Alternative Hypothesis (HA)
States the negation or nullification of the Alternative Hypothesis
Null Hypothesis (H0)
Discovery in subsequent study that preliminary acceptance of the (Ha) was inaccurate
Type I Error
Discovery in subsequent study that preliminary acceptance of the Ho was inaccurate
Type II Error
The proportion of the distribution outside the range of the selected confidence level
Alpha Level
Another name for Alpha
Level of Significance
The three mutually exclusive pairs of null and alternative hypotheses
Pairs of Hypotheses
Tables used to approximate probabilities when standard deviation is unknown
T- Distribuions
Value determined by subtracting 1 from the number of distribution observations
Degrees of Freedom
