Luis Von Ahn

Well, I would like that. I would like that, but yeah. I mean, but the reality is we do spend, I mean, we spend an inordinate amount of time. You know, if you look at our app, it's over time has just become very animated. We spend an inordinate amount of time looking at the precise frames of the animation. We're just like, oh, no, no, see, this is not smooth enough.

Well, I would like that. I would like that, but yeah. I mean, but the reality is we do spend, I mean, we spend an inordinate amount of time. You know, if you look at our app, it's over time has just become very animated. We spend an inordinate amount of time looking at the precise frames of the animation. We're just like, oh, no, no, see, this is not smooth enough.

Well, I would like that. I would like that, but yeah. I mean, but the reality is we do spend, I mean, we spend an inordinate amount of time. You know, if you look at our app, it's over time has just become very animated. We spend an inordinate amount of time looking at the precise frames of the animation. We're just like, oh, no, no, see, this is not smooth enough.

And I'm not to claim that our app is perfect. It's not perfect, but we at least try really hard for it to get as close to perfect as possible.

And I'm not to claim that our app is perfect. It's not perfect, but we at least try really hard for it to get as close to perfect as possible.

And I'm not to claim that our app is perfect. It's not perfect, but we at least try really hard for it to get as close to perfect as possible.

Can you measure that? Yeah, we can. We can, but... not as effectively as you would like to measure it. The answer is yes, Duolingo works. We have measurements. And I'll tell you how we measure it. Unfortunately, this is the only way we know how to measure it reliably. It's not that great of a way, but it is it.

Can you measure that? Yeah, we can. We can, but... not as effectively as you would like to measure it. The answer is yes, Duolingo works. We have measurements. And I'll tell you how we measure it. Unfortunately, this is the only way we know how to measure it reliably. It's not that great of a way, but it is it.

Can you measure that? Yeah, we can. We can, but... not as effectively as you would like to measure it. The answer is yes, Duolingo works. We have measurements. And I'll tell you how we measure it. Unfortunately, this is the only way we know how to measure it reliably. It's not that great of a way, but it is it.

It is you take somebody who's just starting Duolingo, you ask them a bunch of questions about their previous knowledge, you also give them a test to measure how much they know. Then you have them use Duolingo for a long time. because it takes a while for you to actually learn stuff in the language, like use it for a year, use it for two years or something.

It is you take somebody who's just starting Duolingo, you ask them a bunch of questions about their previous knowledge, you also give them a test to measure how much they know. Then you have them use Duolingo for a long time. because it takes a while for you to actually learn stuff in the language, like use it for a year, use it for two years or something.

It is you take somebody who's just starting Duolingo, you ask them a bunch of questions about their previous knowledge, you also give them a test to measure how much they know. Then you have them use Duolingo for a long time. because it takes a while for you to actually learn stuff in the language, like use it for a year, use it for two years or something.

And then at the end of that period, you ask them questions about whether they use other resources, and then you also give them a test to figure out how much better did they get. And it turns out that people who knew nothing before

And then at the end of that period, you ask them questions about whether they use other resources, and then you also give them a test to figure out how much better did they get. And it turns out that people who knew nothing before

And then at the end of that period, you ask them questions about whether they use other resources, and then you also give them a test to figure out how much better did they get. And it turns out that people who knew nothing before

and used Duolingo and did not use any other resources, and then take a test at the end, learn about as much, in some cases, it varies in the study, but either the same or more than the classroom. So we're pretty happy with that. The results actually work. The problem with this way of measuring is that it's very slow. I mean, it takes one or two years for us to get a new measurement.

and used Duolingo and did not use any other resources, and then take a test at the end, learn about as much, in some cases, it varies in the study, but either the same or more than the classroom. So we're pretty happy with that. The results actually work. The problem with this way of measuring is that it's very slow. I mean, it takes one or two years for us to get a new measurement.

and used Duolingo and did not use any other resources, and then take a test at the end, learn about as much, in some cases, it varies in the study, but either the same or more than the classroom. So we're pretty happy with that. The results actually work. The problem with this way of measuring is that it's very slow. I mean, it takes one or two years for us to get a new measurement.

Yeah, I really don't like that, but we have not been able to come up with a better way, despite the fact that we have tried a lot

Yeah, I really don't like that, but we have not been able to come up with a better way, despite the fact that we have tried a lot