Fellow students, let's come to the conclusion of the first assignment.

We are trying to address the so-called "sensory-specific satiety," and we are

asking students to try out different meals

and see how they respond to the level of satisfaction.

In this assignment, we have roughly 3,500 students taking part in it

and collecting all the data and summarize it.

Let's look at the results.

Now in the first meal, Meal A,

we are asking student to have nine gums in a

row and followed by the 10th being the chocolate.

You see that, initially, when the first gum is taken,

the satisfaction level combining from all the students input is about 7.6,

but when we continue to take more gums again and again,

you find that satisfaction level comes down from 7.5, 7.2,

and all the way when it goes to the ninth one that is down to 4.6.

Not very appealing at that time.

But when you give them a chocolate at that time,

the satisfaction level comes back, 7.6.

So it seems that the chocolate is really doing its trait,

and the satisfaction comes back.

Now the same thing happened when the students are trying Meal B:

nine crackers in a row followed by a chocolate.

And initially, cracker is as appealing as the gum because the satisfaction level is 7.7,

but over time again it drops and when it reach the ninth crackers,

the level is only 4.3, even worse than the ninth gum.

Interestingly, at that time, if you combine it where the chocolate is the tenth item,

the satisfaction level came back, 8.3.

Now that's interesting.

Let's see whether we can do a combination.

In Meal C, we tried the first four item as gums

and then five crackers in a row followed by one chocolate.

Initially the gum is giving a good satisfaction,

7.3, and it gradually dropped to 6.1 at the fourth one.

Now with a contrast that you change it to cracker,

that the fifth item admitted bring the satisfaction back to 7.0

but continuing with the crackers the satisfaction goes down again to 5.4.

Interestingly, the tenth item, chocolate,

also brings the satisfaction level back to 8.1.

So we may wonder whether there's anything specific about the chocolate

because every time when you try the chocolate the satisfaction level is pretty high.

So we have this Meal D, which we have student trying ten chocolates in a row.

Obviously when they first try the first chocolate

the satisfaction level is a 8.9, pretty high.

The second one still 8.9, pretty high.

But starting from the third one,

fourth one, fifth one, and goes on,

you notice that the satisfaction level goes down

and down and down and by the time it reached the tenth chocolate,

I would say that it comes down to the level of 4.7.

Very similar to the ninth item as gum

or crackers so suggesting that chocolate is nothing really special.

If you continue to consume it again and again,

again the kind of satisfaction that you would experience is not as much as you expect.

Now combining all these let's look at a composite figure.

We are asked whether there's really some intrinsic value

that associate with specific food items such as crackers,

gums, chocolate and if you, in this composite figure,

you look at the level - how to start with the first item.

Obviously there is something different.

Crackers and gum, well they all score roughly around like seven point something.

But if you try the chocolate, chocolate always score high,

8.9, and sometimes some students go nine point something too.

So what it tells you is that,

while maybe there's an intrinsic value of chocolate,

why its so much appealing to people.

But no matter how appealing it is,

if you continue to consume it again and again

and again, essentially this sensory specific satiety would come

in and it results in a lower and lower level of a satisfaction.

So in order to have a good meal in the future maybe

having more changes of the item would be the way to go.