Midterm Flashcards
Statistic
A numerical measurement describing some characteristic of a sample
Parameter
A numerical measurement describing some characteristic of a population
Population
The complete collection of all elements or subjects (scores, people, measurements, and so on) to be studied
Census
The collection of data from EVERY element in a population
Sample
A subcollection of elements drawn from a population
Discrete data
Result when a number of possible values is either a finite number or a “countable” number (dealing with counts)
Continuous data
Result from infinitely many possible values that correspond to some continuous scale that covers a range of values without gaps, interruptions, or jumps (often times has units of measure attached)
Nominal
Characterized by data that consist of names, labels, or categories only
Ordinal
Can be arrange in some order, but the difference is between the data values either cannot be determined or are meaningless
Interval
Similar to the ordinal level, but the difference between any two data values is meaningful. However, there is no natural zero starting point (where none of the quantity is present)
Ratio
Similar to the interval, but has a natural zero starting point ( where zero indicates none of the quantity is present)
Observational study
Observe and measure specific characteristics, but we don’t attempt to modify the subject being studied
Experiment
A treatment is applied to observe it’s effect on the subjects
Simulation
Mathematical or physical model used to reproduce a situation
Survey
Investigation of characteristics of a population
Placebo
A faux treatment looks like the real treatment
Placebo effect
Occurs when an untreated subject incorrectly believes that he/she is receiving a treatment and reports an improvement in symptoms
Blinding
A technique in which the subject doesn’t know whether he/she is receiving a treatment or placebo
Single blind
The researcher knew which subject received which treatment, but the subjects did not know
Double blind
Neither the researcher nor the subject knows who received a placebo it treatment
Block
A group of subjects (or experimental units) that are similar to test the effectiveness of one or more treatments
Randomized design
This is a way to assign subjects to block through Radom selection
Controlled design
Experimental units are carefully chosen so that the subject in each block are similar in the ways that are important
Confounding
Occurs in an experiment when the effect from two or more variables cannot be distinguished from each other