I am asking this question because I want to research some variables. An example is the RSI where the current RSI is updated every tick. This means that the value of the RSI is fluctuating a lot inside an individual candle. Lets say I want to research what happens after the RSI reaches a value. But if I only take the close prices and not the tick-prices I don't get exactly what I want but a value that is close to the real value (assumption).
A reason for me not to work with tick-data is that is makes the data set very big. Imagine that I want to analyse 4 years of price data using tick-data. That is an immense amount of rows.
Is there someone who tested the close price and tick-data and found a major difference?