Purpose of research (Why): What does a researcher try to accomplish?
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What are the types of study?
Criteria for establishing causation ( relative complete):
Ruling out other causes
An empirical relationship between two variables such that changes in one are associated with changes in the other or particular attributes of one variable are associated with particular attributes of the other.
A casual relationship exists unless the cause precedes the effect in time.
You need a research; you need a study to make sense.
Two variables appear to be related because both are caused by a 3rd variable.
A coincidental statistical correlation between two variables, shown to be caused by some third variable.
The cause must be present for the effect to occur.
The cause will definitely lead to the effect
Taking require courses get you a degree is a necessary cause?
Taking require courses get you a degree is a sufficient cause?
Unit of analysis (Who): Who is to be described or analyzed.
3. Social artifact
An object that is given meaning;Categories that can be analyze; paint, arquitecture, culture, advertisement, magazine,
Drawing conclusions about individuals based solely on the information about groups or geographic areas.
In the rural area there are higher percentage rate of drunk drivers arrested.Rural area people are most likely to be drunk. Is an example of?
Use individual exceptions to deny general patterns.
I know an 90 yr old man that always smoke and doesn’t have cancer and hasn’t die, so smoke doesn’t cause cancer. Is an example of?
Data are gathered at one point in time.
A study based on observations representing a single point in time. Exploratory and descriptive studies are often cross-sectional. Involves observations of a sample, or cross section, of a population or phenomenon that are made at one point in time.
Cross-sectional studies advantages?
quick and inexpensive
Disadvantages of cross sectional studies?
Causal inferences severely restricted
Repeated cross-sectional design which
i) contains same variables
ii) involves an independent sample from the same population.
Every senior in college
Examine specific sub-populations (e.g., born in 1945) as they change over time.
A sub-population defined by a time period (in a specific year or interval of years)
Share time frame: - Graduation year 1998 -Year marry 1990
Examine the same set of people repeatedly over a period of time.
The cause will definitely lead to the effect (If X is there, it guarantees Y to be there.)
Is marry (X) a sufficient cause of divorce (Y)?
Is pregnancy (X) a sufficient cause of abortion (Y)?
Is living (X) a sufficient cause of abortion (Y)?
It is a necessary cause to be women in order to become pregnant.
It is marriage a necessary cause in order to divorce.