Exam 1 Flashcards
Scientific hypothesis
A statement of how the system works, expressed in terms of observable quantities, often qualitative
Statistical models/hypothesis
An explicit quantitative model of potential observations
Usually involves the estimation of one or more parameters
Randomization
Treatments are allocated at random to experimental units
replication
within each treatment or control groups, there are many experimental units
Control
at least one of the “treatments” is a set of experimental units that receive no treatment
Observational studies
No manipulative treatments
Experimental studies
manipulative treatments
Descriptive studies
Does not involve hypothesis testing
parameter
A quantitative measure that describes a charateristic of a population
Estimator
A formula, or function, of the sample data used to estimate some parameter
Estimate
the value you calculate from the sample in order to estimate the parameter
Variance
A component of a measure of precision
Bias
describes how far the average value of the estimator is from the true population value
Experimental bias
errors due to the nature of the experiment such as observer prejudices of equipment malfunction
Statistical bias
Bias = E(X) - u does not equal 0, where E(X) is the expected value of X, and u is the true value of X, which is rarely known
