Data Handling And Analysis Flashcards
Quantitative data?
- Quantitative data is numerical data that can be statistically analysed.
- Experiments, observations, correlations and closed/rating scale questions from questionnaires all produce quantitative data.
Qualitative data ?
Qualitative data is non-numerical language-based data collected through interviews, open questions and content analysis. It allows researchers to develop insights into the nature of subjective experiences, opinions and feelings.
Primary data ?
Primary data refers to data that has been collected directly by the researcher, solely for the purpose of their investigation.
Secondary data?
- Secondary data is information that someone else has collected e.g. the work of other psychologists that has been published in journals or government statistics.
-They are sometimes used by other researchers, as they are often cheaper and more convenient than gathering one’s own primary data.
Meta-Analysis
A meta-analysis is where researchers combine the findings from multiple studies to draw an overall conclusion
Measures of central tendency
Measures of central tendency are descriptive statistics that depict the overall ‘central’ trend of a set of data. There are three key measures: mean, median and mode.
What is a mode?
the most frequently occurring number in a data set.
What is median?
the middle score when the data are in numerical order.
e.g. the median of numbers 1, 2, 3, 4, 5 would be 3),
What is the mean
sometimes referred to as the average, stemming from the method to calculate it: the sum of all numbers in the data set, divided by how many numbers there are in the data set.
e.g. the mean of 1, 2, 3, 4, 5, 6 would be calculated:
[1+2+3+4+5+6] / 6 = 3.5
What is standard deviation
Standard deviation is a measure of dispersion that shows the spread of scores around the mean. The greater the standard deviation the great the spread of scores around the mean.
Formula for standard deviation?
Draw formula
What is a positive correlation?
A positive correlation occurs when two variables are related and as one variable increases/decreases the other also increases/decreases (i.e. they both move in the same direction). For example, you might expect to find a positive correlation between height and shoe size.
Negative correlation
A negative correlation occurs when two variables are related and as one variable increases the other decreases.
- For example, you might expect to find a negative correlation between the school performance of high school students and the amount of time they are absent from school.
Zero correlation
Zero correlation means that there is no relationship between the co-variables in a correlation study.
Normal Distribution
A normal distribution is an arrangement of data that is symmetrical and forms a bell-shaped pattern where the mean, median and/or mode falls in the centre at the highest peak.
What is a skewed distribution?
A skewed distribution is one where frequency data is not spread evenly (i.e. normally distributed); the data is clustered at one end.
What data that is positively skewed ?
Data that is positively skewed has a long tail that extends to the right.
What data that is negatively skewed ?
Data that is negatively skewed have a long tail that extends to the left.
General rule for positive skew?
- the mode is the lowest out of mean , mode and median
General rule for negative skew?
Negative skew mode is normally highest out of mean , median , mode
Nominal data
Nominal level data is frequency or count data that consists of the number of participants falling into categories. ( e.g. 7 people passed their driving test the first time and 6 people didn’t.)
Ordinal data
Ordinal level data is data that is presented in rank order (e.g. places in a beauty contest, or ratings for attractiveness).
Interval data
Interval level data is data measured in fixed units with equal distance between points on the scale. For example, temperature measured in centigrade.
Ratio data
ratio (a continuous scale with an absolute zero).
