Motivations
Who really moves the market?
Financial markets are often portrayed as being ruled by a handful of giants.
But when an entire sector shifts, is it truly the leaders pulling the strings, or is that impression simply a byproduct of size?
In this project, we treat the Nasdaq not as a single voice, but as a set of sectors where firms have very different weights and roles. Rather than assuming large caps dominate, we test it: we rank companies within each sector and track how returns and volatility propagate over time.
Think of each sector as a group moving together — but not everyone steps at the same time. Below, we explore who tends to move first and who follows. We also compare two ways of “building the market”: one where big companies weigh more, and one where every company counts equally. Side by side, this tells us whether performance comes from a few giants or from the whole pack.
Do signals originate from industry leaders and cascade downward? Or do they form collectively, across companies of all sizes?
By following the data, and letting the charts speak, this project offers a clearer view of market power, sector dynamics, and how information actually diffuses through the Nasdaq.
Data Overview
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NASDAQ Stock Market Dataset (Kaggle): daily OHLCV price data for stocks and ETFs + unified metadata (
symbols_valid_meta.csv) -
External Data: NASDAQ Company List (Kaggle): companies only, with Market Cap, Sector/Industry, and IPO Year (
companylist.csv)
External Dataset overview:
Click a sector bubble to reveal the full list of companies in that sector.