Statistical methods

A practical guide to research data analysis.

A reference hub for common statistical methods and research designs. The right method depends on the question, design, outcome, and structure of the data.

Core methods

Methods I commonly work with

Use these descriptions as orientation, not as a substitute for matching the method to the actual study design.

Group comparisons

t-tests, ANOVA & nonparametric tests

Compare groups while considering outcome scale, independence, variance structure, and the assumptions of the selected test.

t-testANOVAANCOVAMann-WhitneyKruskal-Wallis
Regression

Regression & generalized models

Model relationships between predictors and outcomes, including continuous, binary, count, and other response structures.

LinearLogisticPoissonNegative binomialNonlinear
Repeated data

Mixed-effects & longitudinal models

Account for repeated measurements, clustered observations, and hierarchical structures when ordinary regression would treat observations as independent.

LMMGLMMGEERepeated measures
Multivariate

PCA, ordination & community analysis

Explore multivariate structure and compare complex observations using methods appropriate to the data and research question.

PCANMDSRDAPERMANOVAClustering
Study design

Sample size & power

Plan studies around a primary outcome, expected effect, uncertainty, target power, and the actual structure of the proposed analysis.

PowerSample sizeAttritionDesign effects
Learn about sample size analysis →
Time-to-event

Survival analysis

Analyze time-to-event outcomes while accounting for censoring and the way risk changes over follow-up.

Kaplan-MeierCox regressionHazard
Evidence synthesis

Meta-analysis

Combine effect estimates across studies, quantify heterogeneity, and present pooled evidence with appropriate uncertainty.

Effect sizeForest plotsFunnel plots
Diagnostics

Diagnostic test evaluation

Evaluate discrimination and classification performance using sensitivity, specificity, predictive values, and ROC analysis.

SensitivitySpecificityROCAUC
Time series

Trend, seasonality & forecasting

Analyze observations collected over time while accounting for temporal dependence, trend, and seasonality.

TrendSeasonalityARIMAForecasting
Software

R, SPSS, and Python

The software is a tool, not the method. The workflow should be understandable and reproducible in the environment that fits your project.

R
Flexible statistical modeling, visualization, multivariate analysis, and reproducible workflows.
SPSS
Common in academic and applied research workflows, especially for conventional statistical analyses.
Python
Useful for data preparation, statistical analysis, automation, and integrated analytical workflows.
Specialized pages

Go deeper

For project-specific guidance, explore the service pages rather than choosing a method from a list alone.

Statistical analysis for theses →

Ecology & biodiversity analysis →

Sample size & power →

Excel data automation →

Not sure which method fits?

Start with the research question and study design. A statistical consultation can identify the appropriate analysis before you spend time running the wrong one.

Talk through the project
FAQ

Questions about methods

Can you help me choose a statistical test?

Yes. The choice should follow the research question, outcome type, study design, predictors, repeated measurements, and assumptions rather than a simple test-selection chart.

Do you work with R, SPSS, and Python?

Yes. Statistical workflows can be developed in R, SPSS, or Python depending on the project and the software you or your department use.

Can you explain a statistical method in plain language?

Yes. The goal is not only to produce output, but to explain what the method estimates, what its assumptions mean, and how the result relates to the research question.