Linguistics 158: Computer-aided methods in linguistics

John B. Lowe / Department of Linguistics
University of California, Berkeley - Spring 1997

Lies, Damn Lies, and Statistics

week /class: 13 / 23 : Lec Tu , 15 Apr 1997

Some Terms

TermDefinitionExample
Statistics"the process of collecting data and making decisions based on the analysis of these data"
dependent variablethe characteristic you are trying to measure
independent variablevariations which account for differences in the dependent variable (controlled by experimenter)
 subject variables"intrinsic" variablessex, age
 manipulated/experimental variablesvariables which can be changed by experimenter
statisticnumbers based on direct observation
sample statisticstatistic based on a sample
parameteractual ("true") characteristic of whole population
confounderseffects which obsure the relation between your statistic and the parameter you are trying to measure.
populationall instances of a particular type
sampleselected subset of population
descriptive statisticscharacterization of population based on measurements
inferential statisticstentative conclusions about relationships between statistics
nuisance variablesee confounders
nominal scalescale based on "unordered" categories, non-quantitive.favorite color
ordinal scalescale based on ordered relationsage
random selectionrequired assumption for many statistical tests
controlunmanipulated group used to establish validity
Reliabilityconsistency (repeatablity) of measurement
Validityfidelity of measured values to characteristic being considered

Measures of central tendency

Mean
Sum of values divided by number of values ("average")
Median
Middle value in ordered list of values
Mode
Most frequently occurring value

Measures of dispersion

Range
highest value - lowest value.
Variance
Standard deviation
Sum of squares of deviations from mean

Measures of correlation

Graphical representations

Dynamic Philology (Zipf 1935)

Empirical Distributions


Homework 8 : Statistics (due: Apr. 17 )
Homework answers
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