BBA Thesis – Over-Personalization in Virtual Reality
This repository contains the full statistical analysis pipeline for my thesis examining how personalization in virtual reality (VR) influences task performance, efficiency, and user frustration. The work focuses on the distinction between task-relevant and non-task-relevant personalization and investigates when personalization becomes distracting rather than beneficial.
Personalization is often assumed to improve user experience in immersive systems. However, VR introduces high cognitive load, and excessive or poorly aligned personalization may impair task execution.
This study empirically tests whether personalization:
- Improves task performance when it is task-relevant
- Increases distraction when it is non-task-relevant
- Exhibits a non-linear “sweet spot”, beyond which performance declines
- Source: Controlled VR experiment
- Format:
.xlsx(Excel) - Unit of analysis: Individual participant
- Design: Between-subjects experimental study
- Assumption: Small-N, non-normal distributions
total_time_sec– task completion timedfop– path deviation (inefficiency)frustration– self-reported frustration- Task-relevant interaction counts (map, arrow)
- Non-task-relevant interaction counts (decor, UI, objects)
Derived variables:
total_task_relevtotal_non_relevtotal_interactionsefficiency = op / total_time_sec
The script is structured into ten clear sections:
Standard Python data analysis and statistics libraries:
pandas,numpymatplotlib,seabornscipy.statsstatsmodels
Loads the VR experiment dataset directly from Excel into a Pandas DataFrame.
- Aggregates interaction counts into task-relevant and non-task-relevant totals
- Computes total personalization interactions
- Calculates an efficiency ratio to normalize performance by time
- Descriptive statistics
- Shapiro–Wilk normality tests
- Histograms, KDEs, and Q-Q plots
Outcome: Normality assumptions are violated, motivating non-parametric testing.
Participants are categorized into:
- Low
- Moderate
- High
Groups are created separately for:
- Task-relevant interactions
- Non-task-relevant interactions
Thresholds are based on the 33rd and 66th percentiles.
A simplified grouping approach using fixed interaction thresholds is applied to verify robustness of grouping logic.
Tests whether increased task-relevant personalization affects:
- Completion time
- Path deviation
- Frustration
Methods:
- Kruskal–Wallis tests
- Mann–Whitney U pairwise comparisons
- Effect size estimation
- Boxplot visualizations
Replicates Hypothesis 1 using non-task-relevant interaction groups to assess distraction effects.
Explores non-linear effects of total personalization using quadratic regression:
[ Y = \beta_0 + \beta_1(\text{interactions}) + \beta_2(\text{interactions}^2) ]
Models are estimated for:
- Efficiency
- Path deviation
- Frustration
Scatter plots with fitted curves visualize potential inverted-U relationships.
- Median and mean comparisons across personalization levels
- Line plots highlight optimal moderation points
- Visual markers indicate performance-efficient personalization ranges
- Non-parametric tests are used due to small sample size and non-normality
- Effect sizes accompany all inferential tests
- Regression models are exploratory and theory-driven, not predictive
This analysis demonstrates that:
- Personalization is not inherently beneficial in VR
- Task relevance matters more than interaction volume
- Excessive personalization can increase cognitive load, reduce efficiency, and raise frustration
The findings support bounded and selective personalization as a design principle for immersive systems.
- File paths may need adjustment
- No stochastic elements or random seeds are used
- All plots are generated inline
Mahika Vats
BBA Thesis – Virtual Reality, Personalization & Cognitive Load