Data Analysis Flashcards
(30 cards)
What is positive correlation?
As one variable increases the other variable increases
What is negative correlation?
As one variables increases the other variable decreases
What is zero correlation?
When there is no relationship between the variables
What is the ‘third-variable problem’
When a confounding variable is causing the correlation not the two initial ones being measured
What is a correlation coefficient?
It is used to measure the strength and nature of the relationship between two co variables. The correlation coefficient number represents the strength of the relationship and can range between -1 and +1. A perfect positive correlation is +1 and a perfect negative correlation is -1
What kind of graph is used to show correlation sometimes
Scattergram/scattergraph
What are correlations used for?
Correlations are designed to investigate the strength and direction of a relationship between two variables.
Correlation VS experiment?
- correlation looks for a relationship using the data it already has
- experiments have a hypothesis and investigate differences
Strengths of using correlational methods
- can be used when a lab experiment wold be unethical as the variables are not manipulated only correlated
- they measure the strength of a relationship between variables, allowing for further research to be conducted
Limitations of using correlational methods
- not possible t establish cause and effect relationships through conducting a correlation
- can only identity linear relationships and not curvilinear
What is curvilinear?
When something increases/ decreases to a point and then it flattens out/goes the other way
Strengths of weaknesses of qualitative data
- gives richer detail into experiment
- it does not lend itself to be summarized statically
Strengths and weaknesses of quantitative data
- simpler to analyze which saved time and gives stats
- easier to repeat
- tends to be more objective and free from bias
- doesn’t give detail into experiment
What is primary data
- Sometimes called field research
- Original data that has been collected by the researcher
- Data that is participant generated and may have been gathered from: an interview, questionnaire or observation
What is secondary data
- Sometimes called desk research
- Data that has been collected by someone other than the person conducting the research
- Often secondary data has already been subject to statistical testing and significance has been shown
- Secondary data may be gathered from journals articles, books, websites, government data, etc.
Primary data pros and cons
- the data is authentic data gathered to fit the purpose for a particular investigation
- data could be bias due to the person conducting research is the one who wants to see certain results
- requires planning, preparation and resources to gather it
Secondary data pros and cons
- data is inexpensive and easily assessed- meaning minimal effort
- little control over the quantity and quality of data
- the content may not be perfectly fit for what the investigator is trying to research
What is meta-analysis
A statistical method used to combine the results of multiple independent studies addressing the same research question
Pros of using meta-analysis
- don’t need to collect data for yourself
- can get lots of data from all around the world
What do tables include
Raw scores
What do bar charts include
- use discrete data
- title and axis
- separate bars cause each things is separate
What do histograms include
- use continuous data
- bars touch
What do line graphs use
- represent continuous data
- IV on x axis and DV on y axis
Mean definition pros and cons
- Calculated by adding up all the scores in the data set and then dividing by the number of scores.
- Most representative of all the measures of central tendency because it is comprised of the whole data set.
- Most sensitive measure as outliers (extreme scores) can distort the mean.
Can only be used with ordinal and interval data.
