Final Exam Flashcards
Theory
to create explanations for what we see
Hypothesis
create statements derived form theory which is testable and observable
Evidence
test hypotheses with data, cases, and experiments
Causal theory (applicable to political scientists)
- World is in terms of variables and causal explanations, explore this relationship
Independent variable
Presumed cause
Dependent variable
presumed effect/outcome
- Value of dv depends on value of IV
Causal theory breakdown
- Theory
- IV
- DV
- hypothesize
operationalization
process by which abstract concepts are turned into ‘real world’ observations
- you can measure/collect data on unobservable phenomenon
Hypothesis
theory based statement about relationsips that is observed– statement from theory that is testable and observable
Bivariate theory
most causal theories look at relationship between two variables (does X cause Y; does independet variable cause dependent)
most real world problems are multivariate, so how to account for bivariate
control for other factors (z) and other possible causes of Y
Spurious relationships
two or more events or variables are associated but not causally related, due to either coincidence or the presence of a certain third, unseen factor.
how to control for spurious relationship
when z is introduced, relationship bw X and y disappears, if Z is helf constant, then relationship disappears
Additive relationships
Third variable (Z) → DV ← IV (X) X causes Y, but Z also causes Y, both are independent to each other (X does not affect Z, and Z does not influence relationship bw X and Y)
Interactive Relationships
Ex/ Relationship between education and abortion rights depends on gender
- Relationships bw X and Y depends on value of Z
How to control for interactive relationships
- Correlation bw X and Y disappears in both groups= spurious relationship
- Observe correlation still exists and does not differ bw females and males = additive relationship
- Observe correlation still exists in females but not in males (education does impact opinions on abortion rights, but depends/is conditional on gender) = interactive relationship
- Observe correlation still exists in both groups but stronger in females = depends on gender, but greater impact of opinion with females
Types of variables
Categorical
Ordinal
Continuous
Label
description of variable
label: “gender of survey respondent”
values
denominations in which variable occurs
Values: male, female, other
categorical variables
- Limited categories
- Cannot make universally-held ranking distinctions
- Impossible to rank order the categories from least to greatest
- Label: religious ID ;
- values: christian, jewish, muslim
- EX/ race, gender, age, sex
ordinal variables
- Universal ranking distinctions
- Rank order the categories from least to greatest
- Assign scores 1,2,3,4,5 to categories; 5 is assigned for best situation
- Size of difference between categories is inconsistent
EX/ socioeconomic status: low income, middle income, high income
continuous variables
- Have equal unit differences
- Universal ranking distinction
- Size of difference between categories is consistent
- If you can measure it, it is continuous; any value within a range
- Discrete and continuous variables are numeric/scale variables as opposed to categorical variables
- Use term continuous variables for discrete variables
measures of central tendency (typical or average of a variable)
Median
Mode
Mean
Research design
- quantitiative
- qualitative
Quantitative research (3 forms of research)
- uses numerical data for statistical analysis
1. surveys
2. observational studies (to determine if an existing condition is related to a characteristic of interest ie. smoking causes lung cancer)
3. experiments (condition is created by imposing a treatment on the sample) –> researcher both controls and randomly assigns values of iv to subjects
qualitative research
- does not use numerical data for sa
- collects/analyzes non-numerical data (text, video, or audio) to understand concepts, opinions, experiences
- EX/ how does social media shape the image of female politicians?
observational studies
taking the world as it already is no controlled setting
why is randomization important
- if x is determined by pure randomness then it should not be correlated with any variable including Z
- takes systematic differences out of play
- subjects will not be systematically different from one another
- helps show that the observed Y is caused only bc X
To control for possible causes of Y to overcome spurious relationship between X and Y in observational studies
use statistical controls
every causal relationship is….
potentially spurious; bc we can never know for sure until all possible third variables are tested
the most common approaches in political science is
observational designs
investigator can make sure to control for factors he or she has not thought of in:
Experimental Designs
Which approach is stronger, experimental or observational
design?
Experimental Designs