lisa: robert shiller of your university, come in. dan is saying this could be another.com bubble. of that. on the other hand, i can talk like a traditional economist, too. it is a good sign they would be doing an ipo when earnings are negative because lyft and uber are doing cutting-edge changes in technology. the fact that the earnings are negative is not proof of anything. on the other hand, looking at lyft, it is one of the most visible companies in the country. uber.e all used lyft or it has an idea behind it that has the potential to make it overpriced in an ipo. does it give you pause these companies are losing money after being private for so long? they've been in existence and sustain themselves on private capital. does that give you pause? dan: they are obviously looking at the climate of the market. you have an inversion of the yield curve, you have things that could be construed as negative about the market. i think they are racing to get out there. you talk a lot about this on your show. you look at the valuation of lyft and uber. they will be 10 to 11 time sales. snap

let's bring in robert shiller, who joins us from new haven.rful to have you. you said before that perhaps the spirit of thinking with say that the longest bull market in the stock market on to come to an end soon. do you expect negative returns? robert: it's very hard to predict the stock market. the talk about the longest bull market is something that pete last year, and it seemed to have a temporary effect on the market, but now that narrative is fading. we've gotten past that. we are now in record territory, and we are still going fairly well. joe: what is the narrative right now, in your view? robert: unfortunately, there's not just one narrative. some narratives are very a particularike policy rule. other narratives that might help , they tend to be more psychological or social or political. that will about facts be very familiar to you. you might doubt they are driving the market, but they may well be, what else can account for the huge upturn in the stock market that we have seen, and an earnings as well, that reflects buying patterns.