
Describe supervised segmentation in decision trees using a historical data set of correct and incorrect matches. Contrast with unsupervised segmentation; discuss non-tree rule-generation technique and deployable rules.
Analyze how supervised segmentation uses targets to differentiate churn among loyalty program customers, and compare decision trees with rule-based models using the auto classifier and expert tab.
Explore how a rule like store cards equals yes and spend ratio above 0.4 informs purchase, and why decision lists differ from trees by not being mutually exclusive or exhaustive.
Review root and leaf (terminal) nodes; sum leaf samples to the tree’s grand total. Contrast decision lists with trees; unclassified remainder lowers accuracy, while trees are exhaustive and mutually exclusive.
Discover how decision trees support data reduction, reveal interactions in exploration, enable data augmentation, and guide merging of nominal categories to improve model accuracy.
Explore the Titanic data set, its variables such as passenger id, cabin, age, and family counts, and learn measurement levels and train and test data sets for decision tree modeling.
Explore CHAID, the chi-square automatic interaction detection method, an early data mining technique, and learn how it handles scale variables, missing data as a separate category, and settings.
Discover how CHAID uses chi-square tests to split data, adjust with Bonferroni, and handle nominal, ordinal, and scale variables in exhaustive versus standard CHAID.
Use the auto classifier to run multiple CHAID settings and compare Pearson and likelihood ratio approaches, noting chi-square assumptions and trade-offs between exhaustive and faster searches on test data.
Discover how CART uses binary splits with purity and balance, highlights the Gini coefficient, and handles nominal, ordinal, and scale variables, including pruning.
Explore surrogates for missing data in decision trees, using the five variables most correlated with age as proxies to decide branches, and tune their number to balance accuracy and speed.
Discover how pruning, stopping rules, and minimum change in impurity keep cart trees from overfitting by balancing growth with pruning through cost complexity analysis.
Explore CHAID expert settings to control pruning, re-splitting, and thresholds, compare CHAID's tree changes with CART, and assess overfitting versus prediction-focused analysis.
Learn how to compare two models by chaining their predictions, observing how partitions affect outcomes and confidence, and auto-compare without reconfiguring the trade model.
Explore how partition choices, sample size, and pruning affect decision tree stability and accuracy, and compare bagging, boosting, and data prep to build robust ensembles.
Explore how bagging creates multiple models, why data prep matters before bagging, and how boosting and ensemble methods influence accuracy and stability in decision trees.
Explore questions on decision trees, covering binning to handle scale variables, interactive trees, generate filter, costs, and experiments, with a look ahead at decision lists.
Learn how the optimal binning method identifies meaningful cut points for a target variable, such as five for speakers, and why some variables yield non-binary or no splits.
explore data with interactive trees to understand splits, adjust decimal places, compare adjusted probabilities, and force splits for data understanding rather than model customization, guiding expert interpretation.
generate filter demonstrates automatic dropping of unused variables in a model, showing delivery problems can be excluded and neural network pruning and filter combinations for granular decile decisions.
Identify churn-focused decision lists built from not mutually exclusive and exhaustive rules with overlapping segments. Learn to propose rules, run ab tests, and evaluate five churn-prone segments against the population.
Compare decision lists and decision trees for identifying top variables during the exploration phase, evaluate filtering effects, and consider data audit to manage hundreds of variables.
Feature selection relies on variance and does not capture interactions, making it risky for reducing large, messy data. Trees, however, automatically account for interactions during data reduction.
Analyze how misclassification costs shape decision trees, emphasizing churn versus non-churn, adjust cut points, compare costs with cart methods, and interpret confusion matrices under unbalanced data.
IBM SPSS Modeler is a data mining workbench that allows you to build predictive models quickly and intuitively without programming. Analysts typically use SPSS Modeler to analyze data by mining historical data and then deploying models to generate predictions for recent (or even real-time) data.
Overview: Mastering and Tuning Decision Trees is a series of self-paced videos that discusses the decision tree methods (CHAID, C5.0, CRT, and QUEST) available in IBM SPSS Modeler. These techniques produces a rule based predictive model for an outcome variable based on the values of the predictor variables. Students will gain an understanding of the situations in which one would this technique, its assumptions, how to do the analysis automatically as well as interactively, and how to interpret the results. Particular emphasis is made on contrasting CHAID and C&RT in detail. Tuning – the adjusting of parameters to optimize performance – is demonstrated using both CHAID and C&RT.