Receiving a deficiency letter from Nasdaq is a negative regulatory event that indicates potential issues with financial reporting. This can lead to concerns about transparency and reliability among investors, which may result in a short-term negative impact on the stock price. The high relevance score is due to the direct involvement of APXI in the notice, and the importance is significant as it pertains to regulatory compliance, which is critical for maintaining the stock's listing status. The confidence level is high, given the clear cause-and-effect relationship between regulatory notices and stock performance, although there is always some uncertainty in market reactions.