Publications

Price Optimization Combining Conjoint Data and Purchase History: A Causal Modeling Approach

Abstract Pricing decisions of companies require an understanding of the causal effect of a price change on the demand. When real-life pricing experiments are infeasible, data-driven decision-making must be based on alternative data sources such as purchase history (sales data) and conjoint studies where a group of customers is asked to make imaginary purchases in an artificial setup. We present an approach for price optimization that combines population statistics, purchase history and conjoint data in a systematic way.

From sequences to variables - Rethinking the relationship between sequences and outcomes

Abstract Sequence analysis (SA) has gained increasing interest in social sciences for the holistic analysis of life course and other longitudinal data. The usual approach is to construct sequences, calculate dissimilarities, group similar sequences with cluster analysis, and use cluster membership as a dependent or independent variable in a linear or nonlinear regression model. This approach may be problematic as the cluster memberships are assumed to be fixed known characteristics of the subjects in subsequent analysis.

By Satu Helske, Jouni Helske, Guilherme K. Chihaya in Clustering

March 8, 2023

dynamite: An R Package for Dynamic Multivariate Panel Models

Abstract dynamite is an R package for Bayesian inference of intensive panel (time series) data comprising of multiple measurements per multiple individuals measured in time. The package supports joint modeling of multiple response variables, time-varying and time-invariant effects, a wide range of discrete and continuous distributions, group-specific random effects, latent factors, and customization of prior distributions of the model parameters. Models in the package are defined via a user-friendly formula interface, and estimation of the posterior distribution of the model parameters takes advantage of state-of-the-art Markov chain Monte Carlo methods.

Estimating Causal Effects from Panel Data with Dynamic Multivariate Panel Models

Abstract Panel data are ubiquitous in scientific domains such as sociology and econometrics. Various modeling approaches have been presented for the analysis of such data including dynamic panel models, cross-lagged panel models, and their extensions. Existing panel data modeling approaches typically impose some restrictive assumptions on the data-generating process, such as Gaussian errors, effects that are constant in time, or univariate responses. With the goal of surmounting these restrictions, we present the dynamic multivariate panel model (DMPM) that supports both time-varying and time-invariant effects, multiple simultaneous responses across a wide variety of distributions, and arbitrary dependency structures of lagged responses of any order.

Estimating the causal effect of timing on the reach of social media posts

Abstract Modern companies regularly use social media to communicate with their customers. In addition to the content, the reach of a social media post may depend on the season, the day of the week, and the time of the day. We consider optimizing the timing of Facebook posts by a large Finnish consumers’ cooperative using historical data on previous posts and their reach. The content and the timing of the posts reflect the marketing strategy of the cooperative.