Definition of Fair Value

When market valuations extend beyond historical norms, there is pressure to adjust growth and multiplier assumptions to compensate. If Wall Street values a stock at 50 times earnings and the current assumption is 30 times, the analyst would be pressured to revise this assumption higher. There is an old Wall Street adage: the value of any asset (stock) is only what someone is willing to pay for it (current price). Just as stock prices fluctuate, so too do growth and multiplier assumptions. Are we to believe Wall Street and the stock price or the analyst and market