Ch 6 Flashcards
Frequency
Distribution is a tabular arrangement for classifying data into different groups and the number of observations falling in each group corresponding to the respective group
Class limits
The minimum and maximum values defined for a class or groups are called class limits
Class mark midpoint
For a given class average of that class obtained by dividing the sum of upper class and lower class by 2 is called a midpoint
Cumulative frequency
The total of frequency up to an upper class limit or boundary
Less than cumulative frequency
A table showing cumulative frequencies against upper class boundaries
Central tendency
The techniques that are used to determine the central value
Arithmetic mean
Or mean is a measure that determines a value of the variable under study by dividing the sum of all values of the variable by their number
Deviation
Difference of any value of the variable from any constant A
Median
The middle most observation in an arranged data set it divides the data set into two equal parts
Mode
Most frequently occurring observation in the data it is the data that occurs maximum number of times in the given data
Geometric mean
Variable x is the nth positive root of the product of the x.x.x observations
Harmonic mean
Refers to the value obtained by reciprocating the mean of the reciprocal
Moving averages
The successive average which are computed for a sequence of days, year at time
Dispersion
Spread or scatterness of observations in a data set
Measures of dispersion
Determine the degree or extent of variation in a data set
Range
Measures the extent of variation between two extreme observations of a data set
Variance
Mean of the squared deviations observations from their arithmetic mean
Variance
Mean of the squared deviations observations from their arithmetic mean
Standard deviation
Positive square root of mean of the squared deviations of x
Standard deviation
Positive square root of mean of the squared deviations of x
