For an individual investment, or investment portfolio, the investor's a priori (perceived) risk measure can be quantitatively captured by their estimate of the beta, standard deviation, semi-variance (lower partial moment), kurtosis, and/or skewness. Another approach is to view the merits of the investment on a risk-adjusted return basis.
How to measure the investor's perception of risk on the Regional Stock Exchange? The determinants are measured by the subjective judgment of investors? Tversky's theory, Kahnemann, Thaler can serve as a reference.