statistics = ?
a branch of mathematics that involves the collection, description, analysis and inference of conclusions based on data
samples consist of…
a portion of a large group
how do statisticians draw conclusions from large groups?
they derive information from samples and draw reliable conclusions
what are the two major branches of statistics?
descriptive statistics
inferential statistics
descriptive statistics characteristics
- used to summarise the characteristics of a sample or dataset
- e.g., mean, median, variance etc
- first level of statistical analysis
- used to find values that summarise variables, samples and populations
inferential statistics characteristics
- employs techniques to relate variables in a dataset
- e.g., correlation, regression etc
- can be used to estimate forecasts
- more complex level of statistical analysis
- estimates the relationship between multiple variables to infer data patterns
examples of descriptive statistics?
mean
variance
skewness
kurtosis
examples of inferential statistics?
hypothesis testing
analysis of variance (ANOVA)
regression analysis
logit modelling
how are descriptive statistics portrayed?
tables and data visualisation (e.g., graphs)
e.g., histograms, line graphs, scatter plots, bar charts
two parts of descriptive statistics?
measures of central tendency
measures of variability
population?
parameter?
sample?
statistic?
population: set of all elements of interest in a particular study
parameter: a summary measure for a population
sample: a subset of the population
statistic: a summary measure for a sample
what are two world views?
based on certainty (cause and effect)
uncertainty (probabilistic, randomness)
statistics = mathematics?
false
what is probability theory?
the study of likelihood or chance
probability is the connection between descriptive and inferential statistics
what 5 things are statistics good for?
- describing a complex world
- forecasting trends
- capturing relationships
- informing decision making
- evaluating decision making
