Is a common approach to calibration reasonable?

"Model Calibration" article in Encyclopedia of Quantitative Finance states that

. . . a common approach for selecting a pricing measure $\mathbb{Q}$ is to choose, given a set of liquidly traded derivatives with (discounted) terminal payoffs $(H^i)_{i \in I}$ and market prices $(C_i)_{i \in I}$, a pricing measure $\mathbb{Q}$ compatible with the observed market prices

where $\mathbb{Q}$ denotes

a probability measure on the set $\Omega$ of possible trajectories $(S_t)_{ t \in [0,T ]}$ of the underlying asset such that the asset price $\frac{S_t}{N_t}$ discounted by the numeraire $N_t$ is a martingale.

But we know that market prices $(C_i)_{i \in I}$ are generated by fallible human beings! Each of them has rather limited knowledge about "possible trajectories $(S_t)_{ t \in [0,T ]}$ of the underlying asset". Otherwise they wouldn't need the model we are trying to calibrate, would they?

So The Calibration Process receives some prices $(C_i)_{i \in I}$, some arbitrarily choosen mathematical model (i.e. Heston) and produces as an output the calibrated model which supposedly able to give us predictions about the future $(S_t)_{ t \in [0,T ]}$

Why do we believe that The Calibration Process is different from GIGO process?

fiction - How much humour can you afford to have before losing a serious atmosphere?

Background

When I first tried writing fantasy - a long long time ago - I wrote a book that was meant to be really serious and intense. However, I wrote it in a way where the characters joked around, and had more fun than they should have been having in a really dire situation. The whole thing turned into more of a comedic piece rather than being serious fantasy, and lost the atmosphere.

My new masterpiece trilogy is an epic. I've kept it super serious and to the point, and it's gone really really really really well. I'm infinitely happy. However, upon beginning book two, which I started 4 days ago, I have started slipping back into old habits. The characters keep making jokes, and generally enjoying themselves even despite the fact that their home has just been destroyed. I've gone through and edited some of the the humour out and have kept a bit more of the atmosphere of loss and mourning, but I came up with this question while doing it.

Question

Let's get right to it:

How much humour can you have before you lose the serious, intense atmosphere?

Is it right to include humour when something absolutely grievous is going on in the character's lives?

I feel as if I've got a good grip of it at the minute. I know what is silly and I should edit out, and what I should keep. However, this question does intrigue me!

Answer

Any creature that can foresee its own death must learn to laugh or go mad.

In other words, it is a mistake to think that humor is the opposite of seriousness. Humor is the way humans deal with the essential grimness of our lives and their inevitable ends. A serious work that is lacking humor is in some sense missing this essential component of how humans react in serious situations to keep themselves sane.

The opposite of serious is light. You can be light without being humorous. Lightness is essentially the simple avoidance of the grimness of life. It is a way of dealing with the sadness of things by simply refusing to look at them. It is, in many ways, easier to be light if you avoid humor, because humor is always about the absurd, and human absurdity is in some way always about how we pretend we are not all going to grow old, get sick, and die.

It is also possible to be light in dealing with death. This is what the cosy mystery, the Murder She Wrote kind of show does. They present death merely as a puzzle to be solved, separate from its awfulness, it's heartbreak, and its waste.

Humor can be grim. Much of the best humor is very grim. The key is that when you use humor in a serious story, it be serious humor.

Writing seriously is hard -- mentally and emotionally hard as well as artistically difficult. It is possible that you are catching yourself writing something light because that is easier and less traumatizing. In which case, cutting the jokes is not going to make it serious. You will need to rethink the whole piece in a more serious vein.

It is also possible that you are throwing in light jokes in a serious piece, in which case the fix would be to make the jokes serious rather than light (meaning the the joke accepts and acknowledges the grimness and absurdity of human life rather than avoiding it).

Difference between "Expand" and "Outline Stroke" in Adobe Illustrator?

Using Adobe Illustrator, "Expand" and "Outline stroke" seem to produce the same result of converting a path to an object (correct me if i'm wrong). So I'd like to know;

1. Do both commands really perform the same action?



2. When to apply either command?

usability - What is this menu with multiple levels called and should I use it?

What is the above menu called? This menu is similar to one that appears on bookmarks for Google Chrome.

What are the pros and cons of using this pattern?

I'm planning to use this pattern in the dashboard. In my design, the levels are restricted to 3. Is this feasible to use? Is it, user-friendly in terms of usability?

Getting feedback and suggestions from users

I am rebuilding an ERP software.I want to get feedback and suggestions from users on the current software , so that I can build more user-friendly interface and functionality.Suggest me some ideas how to get ideas and feedback from them ?

Answer

You can't beat sitting in a room with the user, watching how they carry out tasks with the software and asking questions. This is the most basic, low-tec version of Usability Testing that there is, but I find it the most informative.

Do it with as many different users as possible (large sample size), using a list of tasks that cover all the functionality that you want to test. Watch for the following things:

• Are some tasks needlessly complicated to complete? Actions that are commmonly repeated should be as streamlined as possible.


• Is there anything in the UI that the user finds confusing? Make a note of why.


• What frustrates the user? Make sure you get to the bottom of this by asking more questions.


• What does the user like? It is important to take note of this so you don't accidently interfere with elements that work well for the user while fixing other usability issues.


• Anything strange? Make a note of anything that strikes you as strange during the test. Perhaps the user is using a feature in an unanticipated way?

Users familiar with the existing software will definitely have wish lists. They are just waiting for someone to ask them (perhaps they already asked for things a long time ago but gave up asking).

registration - How to handle "forgot password" when user has not confirmed email?

If you follow the pattern of allowing users access to your application without having confirmed an email (generally considered good UX), how do handle the case where they forgot their password? Very important in this particular case as the site includes personal health information.

Clearly, sending them an email with instructions to reset it is not appropriate, as their email is not yet verified. I came up with four solutions, but like none of them.

1. 
   

   Freeze a user out after, say, 1 week if they haven't confirmed their email. Then, during this one-week grace period, they cannot recover their email. (Somewhat problematic because it's a security issue to reveal whether an email address is registered during forgot password, so we'd be unable to actually communicate that password reset is unavailable to them based on not having confirmed).

   
   


2. 
   

   Add "security question" to signup. Bad for fairly obvious reasons.

   
   



3. 
   

   Just not let them use the site without confirming their email. Also bad.

   
   


4. 
   

   Just let them recover their password even without a confirmed email, but add some text in the site "if you haven't confirmed your email, someone could get access to your private health information." This would show in a banner at the top of the screen until they register, and have the option to have the email re-sent to any email address they choose. This might be the worst security case of all.

   
   

Any ideas?

effects - Preventing reverse search engines from finding the origin of your image?

I am planning to make a game, where I give the user an anime related image and they have to guess where its from.

However, most of the images, specially from popular anime are easy to use on Google reverse search to find and pin point the anime.

I've tried to see if I could make so it would not recognize the image but unhappily my tricks were not good enough.

Original image:

Grey-scale with horizontal flip:

Watermarking:

Puzzling the image with grey-scale:

Grey-scale with horizontal and vertical flip worked for this image but doesn't always work:

Also the above mentioned methods are rather easy for people to guess the anime.

I would like to know if there any good trick, that I could use on my images to make so it would not work on reverse search engines and yet not be so overcomplicated that I can implement on my program.

For example grey-scale, cropping, flipping are rather easy things to achieve in C#.

Answer

I think you were on the right track with your watermarking option, but you left too much of the original image in tact. Here are two images I tried that Google was unable to find:

Checkerboard

Reverse image search results

Mosaic

Reverse image search results

Another example

Reverse image search results

The first image returns a lot of "checkered flag" results, and the second returns lots of mosaic/collage images. Size does matter! I initially tried it with a much smaller checkerboard pattern (16px); Google was still able to identify that. These 32px squares seem to be a happy medium.

Based off of the information that DanS provided, I think this would be a dependable technique to fool Google (and easily automated!). I can only presume that someone who was able to identify this anime would still be able to do so from these images.

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^{Ironically, the images I have created will eventually be indexed by Google and lead to this post, defeating the purpose!}