# Shared Flashcard Set

## Details

Management Opts 215 Test 1
Chapters 1,2,3,4,5
81
Management
02/16/2012

Term
 Statistics
Definition
 1) commonly means a collection of numerical facts or data 2) A science of collecting, presenting, analyzing, and interpreting numerical data
Term
 Descriptive Statistics
Definition
 Organizing and summarizing numerical data in order to describe the various features of the data.
Term
 Inferential Statistics
Definition
 Procedures and methods that can be used to make inferences (or generalization), predictions, and decisions about the population using the information contained in a sample.
Term
 Probability
Definition
 1) commonly means a chance 2) a mathematical means of studying uncertainty, and used as a tool for inferential statistics
Term
 Population
Definition
 A collection of all the elements under study (about which we are trying to draw a conclusion) or a collection of all the measurements understudy.
Term
 Observation
Definition
 A single member of a collection of item that we want to study
Term
 Variable
Definition
 A characteristic of a population unit.
Term
 Sample
Definition
 A part of the population
Term
 Parameter
Definition
 A numerical descriptive measure of the population
Term
 Statistic
Definition
 A numerical descriptive measure from a sample
Term
 Census
Definition
 Evaluation of each and every unit (element) in the population under study; this data contain complete (and perfect) information about the population.
Term
 Simple Random Sample
Definition
 A sample drawn such a way that each element of the population has the equal chance of being selected. Three ways of taking a simple random sample  1) draw tickets out of a hat 2) use random number tables 3) use MS Excel: FORMULA>INSERT FUNCTION>Math&TRIG>RANDBETWEEN
Term
 Systematic Sample
Definition
 Select every K-th item from the list
Term
 Stratified Sample
Definition
 Select randomly with defined strata
Term
 Cluster Sample
Definition
 Like a stratified sample except strata are geolgraphical regions
Term
 Judgement Sample
Definition
 A non-probability sampling methos that relies on the expertise of the sampler.
Term
 Convenience Sample
Definition
 Select whatever is handy
Term
 Qualitative data
Definition
 Non numerical and categorical
Term
 Quantitative data
Definition
 Numeric
Term
 Discrete
Definition
 Assumes only specific points on a scale
Term
 Continuous
Definition
 Assumes all values within an interval
Term
 Nominal Scale
Definition
 Applies to data that are divided into different categories, and these categories are used for identification purposes, e.g., female=0, male=1
Term
 Ordinal Scale
Definition
 Applies to data that are divided into different categories that can be ranked, e.g., bad=0, fair=1, good=2, bond ratings: AAA, AA, A, BBB, BB, National Threat Advisory: G,B,Y,O,R ect.
Term
 Interval Scale
Definition
 Applies to data that can be ranked and for which the difference between two values can be calculated and interpreted, e.g., temperature, calendar time.
Term
 Ratio Scale
Definition
 Applies to data that can be ranked and for which the ratio between two values can be calculated and interpreted, e.g., income, weight.
Term
 Ordered data
Definition
 data arranged in ascending order or in descending order, easy to pick out extremes, typical values, and concentration of values.
Term
 Stem and Leaf Plot
Definition
 Partly tabular and partly graphical way of summarizaing data, and suitable for smaller data sets.
Term
 Frequency Distribution
Definition
 A summary table in which data are arranged into conveniently established, numerically ordered class groupings or categories. The number of observations falling in each class is call the class frequency. It is a way of organizing raw data into a meaningful way
Term
 Range
Definition
 =Largest observation-smallest observation
Term
 Stuges' Rule
Definition
 k=1+3.3log10(n)
Term
 Bin width
Definition
 Divide the range by k(sturges' rule) to determine class size.
Term
 Histogram
Definition
 A graph made of rectangles whose areas are proportional to the relative frequencies of respective classes.
Term
 Open Ended Class
Definition
 A class without either a lower limit or an upper limit
Term
 Polygon
Definition
 Another way of displaying a (relative) cumulative frequency distribution
Term
 Ogive
Definition
 A graph of a (relative) cumulative frequency distribution.
Term
 Density
Definition
 The height (y-axis) of a relative frequency histogram
Term
 Pie Chart
Definition
 A circle divided into portions that represent the relative frequencies.
Term
 Mode
Definition
 The location at which a relative frequency distribution peaks
Term
 Modal Class
Definition
 The class that contains a mode.
Term
 Measures of Central Tendency
Definition
 (center, location): measures the middle part of a distribution or data; these include standard deviation and range.
Term
 Parameter
Definition
 A numerical descriptive measure computed from the population measurements (census, data)
Term
 Statistics
Definition
 A numerical desciptive measure computed from sample measurements.
Term
 Deviation from the mean
Definition
 Observation minus the mean. The mean is a measure of the center in the sense that it "balances" the deviations from the mean.
Term
 Median
Definition
 The middle value of data when ordered from smallest to largest.
Term
 Midrange
Definition
 The average of the largest and smallest observation
Term
 Trimmed Mean
Definition
 The mean of data after removing the highest and lowest k percent of the observations.
Term
 Geometric Mean
Definition
 The n-th root of the product of n values.
Term
 Geometric Mean Rate of Return
Definition
 An average rate of change; a good way to sort out effects that are multiplicative.
Term
 Population Variance
Definition
 The (population) variance is the average of the squared deviations from the population mean.
Term
 Sample Variance
Definition
 The (sample) variance is the "average" of the squared deviations from the (sample) mean.
Term
 Coefficient of Variation
Definition
 A relative measure of the amount of variation with respect to the mean. Note the standard deviation is an absolute measure of variation.
Term
 Standardized Score
Definition
 Sometimes called (z-scores) represents the signed distance from the mean measured in units of standard deviation.
Term
 Chebychev's Theorem
Definition
 For any sample or population data the proportion of observations that lie within k standard deviations from the mean is at least 1-1/ksquared. This describes the distribution of data using the mean and the standard deviation together.
Term
 Empirical Rule
Definition
 When the distribution of (smaple or population) data is approximately bell shaped(or mound-shaped), then approximately 68% of the data are within 1 standard deviation from the mean, approximately 95% of the data are within 2 standard deviation from the mean, and aproximately 99% of the data are within 3 standard deviation from the mean.
Term
 Outliers
Definition
 Extreme observations not conforming to the rest of the observation. As a rule of thumb observations that are three standard deviation above or below the mean are considered as outliers.
Term
 First Quartile
Definition
 also called lower quartile, and denoted by Q1, is the 25th percentile.
Term
 Third Quartile
Definition
 Also called upper quartile and denoted by Q3, is the 75th percentile.
Term
 Inter-Quartile Range
Definition
 Q3-Q1, and is a measure of variability.
Term
 Midhinge
Definition
 (Q1+Q3)/2, a measure of location
Term
 Box and Whisker Plot
Definition
 a graphical method of displaying the quartiles, ranges, and extreme values of data. In a box plot the left "I" (also called the left hinge) is at Q1, the right "I" (right hinge) at Q3, and "I" inside of the box is at the median, the right (left) whisker extends out from the right (left) hinge to the largest(smallest) observation with 1.5 IQR above (below) the right (left) hinge, observations beyond the reach of the whiskers are considered outlying observation.
Term
 Probability
Definition
 1) commonly means a chance 2) a mathematical means of studying uncertainty, and used as a tool for inferential statistics.
Term
 Random Experiment
Definition
 Any activity from which an outcome, measurement, observation, or result is obtained, and outcomes cannot be predicted with certainty.
Term
 Basic outcome (elementary outcome)
Definition
 Each possible outcome of a random experiment.
Term
 Sample Space
Definition
 The set of all possible basic outcomes, usually denoted by S.
Term
 Event
Definition
 A subset of the sample space, usually denoted by A,B,C,....
Term
 Event Occurs
Definition
 If any one of the basic outcomes in the event occurs.
Term
 A simple event (elementary event)
Definition
 an event with only one basic outcome, usually denoted by Ei.
Term
 Mutually Exclusive
Definition
 Two events. if one and only one of them occur.
Term
 Classical Method
Definition
 every possible outcome of an experiment is assumed to be equally likely, known a priori by natire of the experiment.
Term
 Empirical Method
Definition
 (relative frequency method): the probablilty of an outcome is the relative frequency of the outcome, that is, the frequency of occurrences of the outcome divided by the number of trials repeated.
Term
 Subjective Method
Definition
 The probability of an event relects a person's degree of belief that the event will occur based on experience, intuitive judgement, or expertise.
Term
 Complement Probabilty
Definition
 An event A, denoted by A' consists of all basic outcomes in S that do not belong to A.  P(A)=1-P(A')
Term
 Intersection (Joint Probability)
Definition
 Two events A and B, denoted by A ^ B or AB consists of all basic outcomes that belong to both A and B. The probability of the intersection of two events, denoted by P(AB)
Term
 Union
Definition
 Two events A and B, denoted by P(A union B) consists of all basic outcomes that belong to either A or B or both.
Term
Definition
 P(A union B)=P(A)+P(B)-P(A^B)
Term
 Conditional Event
Definition
 A given that B has occured is denoted by A|B, and its probabilit is  P(A|B)=P(A^B)/P(B)
Term
 Odd in favor of A
Definition
 P(A)/P(A')=P(A)/1-P(a')
Term
 Odds against A
Definition
 P(A')/P(A)=1-P(A)/P(A)
Term
 Marginal Probability
Definition
 The probability that an observation will show any single specific characteristic and is obtained by summing the appropriate joint probabilities over all values of other variables.
Term
 Multiplicative Rule
Definition
 P(A^B)=P(A)P(B|A) P(A^B)=P(B)P(A|B)
Term
 Independent Events
Definition
 If and only if one of the following holds: 1) P(A|B)=P(A) when P(B) does not =0 2) P(B|A)=P(B) when P(A) does not =0 3) P(A^B)=P(A)P(B)
Supporting users have an ad free experience!