Quantitative Research Flashcards
Quantitative Variable
Such as height that is typically measured by assigning a number to each other
Categorical variable
Quality such as chosen major and is typically measured by assigning a category label to each individual
Operational Definition
The definition of the variable in terms of precisely how it is to be measured
example of operational definition
Depression can be operationally defined as peoples scores on a paper - and pencil depression scale
Populations
Very large group of people
Ex: All americal teenagers
Sample
Small subset of the population
Simple Random Sampling
Every member of the population has an equal chance of being selected for the sample
Convenience Sampling
Sample consists of individuals who happen to be nearby and willing to participate
Experimental Resarch
Researchers who want to test hypothesis about causal relationships between variables
Determine causal relationships
Independent Variable
Variables that can be manipulated
Dependent Variable
Variable that’s being measured
Extraneous Variables
Any variable other than the dependent variable
Non experimental research
Naturalistic Observations
Lab studies
conducted in lab lol
Field studies
stay that is conducted in the real world, in a natural environment
Internal Validity
Refers to the degree to which we can confidently infer a causal relationship between validity
More extraneous variables decrease _________
Internal validity
External validity
Refers to the degree to which we can generalize things to other circumstances in the real world environment
High external validity means ________
Low internal validity
Field experiments
Where an independent variable is manipulated in natural setting and extraneous variables are controlled
Descriptive statistics
Used to organize or summarize a set of data
Mode
Most frequently occurring
Median
Midpoint
mean
Average of the distribution
Range
Highest - lowest
Standard deviation
sophisticated measure of dispersion that measure average distance of scored from the mean
Variance
Standard deviation squared
Also measures the distance of scored from the mean bit in a different unit of square
Correlational coefficient
-1 to 1
-1.00
Strongest negative correlation
0
no relationship
1.00
Strongest positive correlation
A good example of positive correlation
height increases and weight also tends to increase
Inferential statistics
Allows researchers to draw conclusions about a population based on data of a sample
Statistically significant
A effect that is one that is unlikely due to random chance therefore likely represents a real effect in the population
Type 1 error
False positive
Type 2 error
missed opportunity. Results are not statistically significant
