Sometimes it is necessary to use daily data to obtain a data series of the desired length. Ironically, high-frequency data improves the precision of sample variances, covariances, and correlations but not the precision of the sample mean. High-frequency data are more sensitive to asynchronism across variables.”
I came across the above statement while doing candidate resources. could you please explain asynvhronism?
There is nothing to explain here actually. Asynchronism has its literal meaning. The more the frequency of data, the more sensitive it is to a lack of synchronicity across variables.