This thesis examines the statistical and economic performance of modeling and predicting equity index returns by application of various statistical models on a set of macroeconomic and financial variables. By combining linear principal component regression, vector autoregressive models, and LSTM neural networks, the authors find that while a majority of the models display high statistical significance, virtually none of them successfully outperform classic portfolio theory on efficient markets in terms of risk-adjusted returns. Several implications are also discussed based on the results.Detta examensarbete undersöker den statistiska och ekonomiska prestationen i att modellera och prognostisera aktieindexavkastning via applikation av flerta...