I want to check for the assumptions of linearity in my logistic regression model, which states that the logit of the probability is a linear combination of predictors. It might be the case though, that I need to transform one or more of the predictors for a better fit. What I am asking for is some tools to visualize the relationship between fitted probabilities and observed probabilities.  Thanks in advance!
For linear regression, we can check the diagnostic plots (residuals plots, Normal QQ plots, etc) to check if the assumptions of linear regression are violated.  For logistic regression, I am having trouble finding resources that explain how to diagnose the logistic regression model fit. Digging up some course notes for GLM, it simply states that checking the residuals is not helpful for performing diagnosis for a logistic regression fit.  Looking around the internet, there also seems to be various "diagnosis" procedures, such as checking the model deviance and performing chi-squared tests, but other sources state that this is inappropriate, and that you should perform a Hosmer-Lemeshow goodness of fit test. Then I find other sources that state that this test may be highly dependent on the actual groupings and cut-off values (may not be reliable).  So how should one diagnose the logistic regression fit?
How can I easily share links or text between my Android phone and my laptop? Hilbert space of harmonic oscillator: Countable vs uncountable? Hm, this just occurred to me while answering another question:   If I write the Hamiltonian for a harmonic oscillator as $$H = \frac{p^2}{2m} + \frac{1}{2} m \omega^2 x^2$$ then wouldn't one set of possible basis states be the set of $\delta$-functions  $\psi_x = \delta(x)$, and that indicates that the size of my Hilbert space is that of $\mathbb{R}$.  On the other hand, we all know that we can diagonalize $H$ by going to the occupation number states, so the Hilbert space would be $|n\rangle, n \in \mathbb{N}_0$, so now the size of my Hilbert space is that of $\mathbb{N}$ instead.  Clearly they can't both be right, so where is the flaw in my logic? I recently ran across elliptic curve crypto-systems:    (Brown University)  (Wikipedia)  (IEEE)  (RSA.com)   It seemed to me to be great alternative to RSA as the de-facto cryptosystems to be used in banking and financial systems and in the public key infrastructure for certificates, but is not used! If someone can explain why this is not done, it would be very helpful. A comparison between traditional RSA and an elliptic curve cryptology would be helpful.  To begin with:  Advantage of RSA:   Well established.   Advantages of elliptic curve:   Shorter keys are as strong as long key for RSA (see the IEEE paper) Low on CPU consumption. Low on memory usage. How can I keep low resolution textures pixelated? Website giving pronunciations of English words recorded in different dialects? I'm aware that there are certain websites around that provide recorded examples of English words pronounced in different accents/dialects.  Could anybody list some of them? Is the current obtained using Ohm's law that which passes through the resistor or that which passes through the circuit? Shouldn't the current passing through a resistor be lesser than that which passes through a circuit? My understanding is that since Current = Charges/Time. If there exists a resistance to the flow of charges, then that must mean the charges slow down, meaning that more time is required to pass through a point. So, the current should then decrease. But, since this opposition to the flow of charges doesn't exist in the ENTIRE circuit, it should really only decrease the current in the resistor, right? Am I confusing the resistance of the resistor with the resistance of the wire? Any help will be appreciated! Thanks a bunch for lending me some of your time :D How can a single slit diffraction produce an interference pattern? How can a light passed though a single slit produce a similar interference pattern to the double-slit experiment? How does the diffracted wave produce the points of cancellation and reinforcement, if there is only one wave? What is the concept of erasure in generics in Java? What is the concept of erasure in generics in Java? For any triangle with sides $a$, $b$, $c$, show that $a^2b(a-b)+b^2c(b-c)+c^2a(c-a)\ge 0$ For any triangle with sides $a$, $b$, $c$, prove the inequality $$a^2b(a-b)+b^2c(b-c)+c^2a(c-a)\ge 0 .$$   This is IMO 1983 problem 6.  I tried substituting $a=x+y$, $b=y+z$, $c=z+x$ but well it doesn't help in any sense except wasting 3 pages that lead to nothing (please don't mind the joke). Using $a=2R\sin A$, $b=2R\sin B$, $c=2R\sin C$ also didn't lead to anything for me. Could you give me a hint for finding the proper substitution? Why does the mirror modifier sometimes give me an overlapping mesh? Navigate folder structure in Open/Save File Dialog with keyboard? After hitting ⌘-O, how can I navigate my folders and select a file to open using only my keyboard?   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When I do sudo supervisorctl start my_app it simply hangs until I do CTRL-c, then I find the error above in the supervisord.log file.  Does anyone have a clue about what I am missing? Why are some of my screen-recording/capturing/sharing applications (or app features) not working in Ubuntu 17.10 (and later releases)? To estimate the time for brute-force attack we need to compute keyspace size divided by hash rate, where the hash rate (hash/second) varies depending on the computer's capabilities.  The website  shows the hash rate for different computers.  Can you explain the following two confusing phenomena?   The hash rate decreases as the message size increases. Core i3 has a higher hash rate than Core i7 for SHAKE128. Short expression to convey "but consider the source" Universal type tranformer in Haskell New Beamer Version: Transparent Title Page Boxes Using trickle to limit the bandwidth of a VirtualBox VM I'm trying to limit the bandwidth of a virtual machine running via VirtualBox.   trickle -d 5 virtualbox doesn't work, I believe because of an issue with child processes (trickle -d 5 sudo apt-get upgrade doesn't work either)  How can I limit the download/upload bandwidth of VirtualBox's VMs? How can I block all traffic *except* Tor?