Stats Flashcards
Process of Research in Conducting Statistics
- First determine average results
- Then individual variations
- Then ethical reporting - full disclosure is crucial for accurate interpretation, giving other researchers the chance to replicate the study
The Ethical Imperative: Why Understanding Stats Matters
- Transparency and accountability
- Advancing the field Ethical data practices
- Ethical Data Practices are crucial for maintaining public trust and to avoid misrepresentation and unintended bias of psychological traits
Implications of Misreporting
- Overgeneralisation - misleading one-size-fits-all impression of therapy effectiveness
- Patient harm - wasted time on ineffective treatments
- Research mistrust - damages credibility of psychological studies
- Ethical responsibility - researchers must present complete picture, including limitations
Measures of Central Tendency
- mean, the most common, however others might be more appropriate
- median
- mode
Measures of Dispersion/Variability
- Range
- Variance
- Standard deviation
- Interquartile range
Histograms and Bar Charts
- Graphs for understanding data
- How often the data appears - histogram
- Compare the magnitude of different categories - bar charts
Boxplots
Give median value, interquartile range and the spread of data
- Can reveal key characteristics such as presence of skewness, extent of variability
Scatterplots and Correlations
- Relationships between two variables
- Trends, clusters and outliers
Importance of Data Cleaning and Preparation
- Identifying error - mistakes that might skew the data
- Handling missing data - appropriate methods to handle them
- Standardised formats - all data is the same format so it can be compared
- Transforming variables - apply necessary transformations to meet stat assumptions
Strategies for Handling Missing Data
- Imputation - replace missing values with estimate based on patterns in the existing data
- Listwise deletion - remove any cases with missing data (this can reduce statistical power and introduce bias if the missingness is not random)
- Multiple imputation - generate multiple plausible values for each missing data point to account for uncertainty, then pool the results
- Analysis of missingness - investigate the patterns and mechanisms behind missing data to select the most appropriate handling method
Interpreting Descriptive Stats
- Visualising the data - through patterns, outliers and relationships in graphs etc
- Contextual interpretation - understanding real-world implications of descriptive statistics
- Practical significance - evaluating the magnitude of its effects
Ethical Considerations in Data Presentation
- Transparency
- Avoiding bias
- Context matters
- Responsible reporting
Avoiding Common Pitfalls in Descriptive Stats
- Misinterpreting visualisations
- Choosing inappropriate analyses
- Data entry errors
Practical Applications of Descriptive Stats
- Research design
- Psychological assessment
- Intervention evaluation
- Data visualisation
The Data Analysis Process
- Collect
- Organise
- Analyse
- Interpret
- Collect
- Experimental measurements
- Behavioural observations
- Psychological test scores
Survey responses
- End up with spreadsheets
- Everything in row one is for participant 1 and so forth
- Columns incorporate different variables
- Organise
- Median, mean, minimum and maximum
- Summarise data to find averages → the first step
- Not interested in individual data, but summative data
- Box plots, histograms, relationships of variables (scatter plots)
- Analyse
- Descriptive statistics, differential statistics, to put these into words for specific variables, making sense of the spreadsheets
- Interpret
- What do these numbers mean for the research, what does it suggest
- Must be done accurately
- “This suggests…”
Quantitative Variables
measurable quantities like age, height, test scores (anywhere within a range)
Qualitative Variables
descriptive categories such as gender, eye colour, mood
Types of Data
- Numerical
- Categorical (grouping data)
- Ordinal (ranked data like likert scales)
- Continuous (infinitely divisible data like reaction time)
Nominal Scale - Identity
- Used for categorical variables,
- Numbers are arbitrary, acting as labels instead of names, they indicate difference, not size or order
Ordinal Scale - Identity + Order
- Scores can be ranked/ordered
- Indicate differences and scale
- Nothing more than rank order
- No objective distance between any two points on the scale
- Not measurable