Is Ambarella, Inc. overvalued or undervalued?

As of 30 August 2018, Ambarella, Inc. has moved from a valuation grade of very expensive to risky, indicating a significant shift in its market perception. The company is currently considered overvalued, especially given its negative P/E ratio due to being loss-making. Key ratios include a Price to Book Value of 3.97, an EV to EBITDA of -23.62, and a ROCE of -35.47%.
In comparison to peers, Cirrus Logic, Inc. is rated attractive with a P/E of 15.99 and an EV to EBITDA of 10.25, while Tower Semiconductor Ltd. is rated fair with a P/E of 21.98 and an EV to EBITDA of 7.18. The stark contrast in valuation metrics highlights Ambarella's overvaluation in the current market. Additionally, the company's stock has underperformed against the S&P 500, with a year-to-date return of -29.11% compared to the index's 2.44%.