This　research　utilizes　data　mining　and　text　analysis　methods　to　extract　investor　attention,　emotion,　and　opinion　convergence　from　stock　forums.　A　Restricted　Reverse　MIDAS　model　is　constructed　to　explore　the　dynamic　effects　of　real-time　public　opinion　on　intraday　high-frequency　stock　index　and　trading　volume.　The　empirical　results　demonstrate　a　positive　impact　of　forum　public　opinion　on　high-frequency　stock　index　and　trading　volume,　with　a　time　attenuation　effect　observed.　Specifically,　midday　public　opinion　significantly　influences　the　afternoon　high-frequency　stock　index,　exhibiting　an　initial　increase　and　subsequent　decrease　in　investor　sentiment,　while　investor　attention　and　opinion　convergence　exhibit　a　decreasing　trend.　Nighttime　attention　and　sentiment　primarily　affect　the　next　morning＇s　high-frequency　stock　index.　Moreover,　the　real-time　emotional　impact　on　the　stock　market　varies　across　different　environments.　©　2023