Orphaned Tag Wikis are sad. They hang around, shambling, and groaning and wait... that's zombies. Or maybe teenagers.  What does happen in many cases is they can be ambiguous, get misused, and on some larger sites end up needing many man hours of cleanup.   On the other hand, people who create a tag ought to know what it's for. We can change them later. If its a new user, it also ensures the user's put some thought into it, and lets people review it better. Making them write at least an excerpt, that's peer reviewed. In short, can we make sure that the need and goal of any new tag is clearly stated when its created?
When a new tag is created, should there be some kind of notification to the user?  This could serve a dual purpose:   To make the user check that this tag is really required.  Is it spelt right? Might there be a more appropriate tag to use instead? - See  To promote the creation of tag wikis.   These are both beneficial to the site.  Making users think twice about their tags reduces the amount of retagging edits that are needed and reduces noise.  Promoting tag wikis means that more new tags would come with explainations, making them more user-friendly for others.  Creating a new tag is a privilidge earned at 1500 reputation.  Hopefully the user has gained a feel for the ethos of SO by this point, and is either enjoying being a contributer or is mainly asking good, well recieved questions.  The user is probably also wanting to contribute to the site further (even if just to gain reputation), and so it makes sense to me that there should be a gentle push towards taking a little bit of time to write a short wiki for the tag you just created.  By no means should this be mandatory, and the precise format of this gentle push is more in the scope of UX guys to think up, but I wanted to see how people felt about some kind of discreet notification.  I thought of two forms this notification could take:  Option 1 - at the time of tagging      Option 2 - after posting      Update: Raphael has suggested in the comments that this could be implemented as a 10K user tool.  While I think that's a good idea on its own, I don't think it should be used instead.  I think that encouraging users with less than 10K to complete wikis for their own tags is likely to get some wikis written because there is a sense of ownership over your own tag, and by giving it a wiki you are giving it a better start in life. As with a child, users will want to equip their tag with the tools it will need to survive in the big wide world.
Proving that $a \mathbb{Z} \cap b\mathbb{Z} = \operatorname{lcm}(a,b)\mathbb Z$ Given $m \in \mathbb{Z}$, let $m\mathbb{Z}$ denote the set of integer multiples of $m$, i.e. $m\mathbb{Z} := \{mk\mid k \in \mathbb{Z}\}$.   Now let $a,b \in \mathbb{Z}$ with $a,b$ not both $0$. Prove that $a\mathbb{Z} \cap b\mathbb{Z} = \operatorname{lcm}(a,b)\mathbb{Z}$.   I am trying to write a proof for this, but I am unsure of what method to use. Also I am confused by $mk\mid k$, because wouldn't $m=1$ for this to be true. Why can't I do foreach (var Item in DataTable.Rows)? Reporting Mann-Whitney U-Test without homogenity of variance The Mann-Whitney test requires homogeneity of variance if a median difference is suppossed to be statistically significant.  In case homogenity of variance is not met, but the test is significant:  Which aspects of the test can I report? Reverse (parse the output) of Arrays.toString(int[]) How to change material's color in blender game engine? Why is the product of all units of a finite field equal to $-1$? Suppose $F=\{0,a_1,\dots,a_{q-1}\}$ is a finite field with $q=p^n$ elements. I'm curious, why is the product of all elements of $F^\ast$ equal to $-1$? I know that $F^\ast$ is cyclic, say generated by $a$. Then the product in question can be written as  $$ a_1\cdots a_{q-1}=1\cdot a\cdot a^2\cdots a^{q-2}=a^{(q-2)(q-1)/2}. $$ However, I'm having trouble jumping from that product to $-1$. What is the key observation to make here? Thanks! US / Mexican border data I'm interested in locating free GIS shapefile data representing the US / Mexican border. I have found a point layer depicting the border crossing points but I'm interested in a polyline feature representing the actual border. Bayes rule logic. Why we do use this? $f: \mathbb{R} \rightarrow \mathbb{R}$ is a continuous function. Assume that $\lim_{x \rightarrow \pm \infty} f(x)$ exist and are finite. Prove that $f$ is bounded.  So to show that $f$ is bounded, I must show that $\exists M \in \mathbb{R}$ such that $|f(x)| \leq M$ for all $x \in Dom(f)$. Assuming that $f(x)$'s limit exist, then I know that $\forall \epsilon  &gt; 0$, $\exists N$ such that for $n &gt; N$, $|f(n) - L| &lt; \epsilon$. But I am having trouble with figuring out how to connect the two ideas together. parsing XML file gets UnicodeEncodeError (ElementTree) / ValueError (lxml) Is the proposal creator guaranteed moderator status? When an Area 51 site goes into public beta is the person who created the proposal one of the pro tem moderators or not?  They are talking on Area 51 about combining all the sports proposals into , including one I proposed. Would I still be one of the pro tem moderators on the merged site?  Is the proposal creator afforded any elevated status or perk? Call Servlet and invoke Java code from JavaScript along with parameters How to understand intuitively the Stolz-Cesaro Theorem for sequences? I have to give a presentation on the theorem in Real Analysis with a fellow student. While I've looked over the  and verified that, yes, step B does indeed follow logically from step A, etc. and have internalized the proof to the extent that I can replicate it myself on paper, I still feel that I have made little progress as to why this theorem works the way it does, i.e. what is the intuition behind the theorem, such that it should make sense that it follows the way it does. Therefore I ask: what kind of intuition is there about this theorem? It would also be helpful to understand how the theorem can be used effectively in analysis.  I have seen it referred to as a sort of L'Hopital's rule for sequences, which certainly seems to make sense, but I similarly have little intuitive understanding of how that rule works, either.  I am asking this question not only for my personal understanding, but also for the sake of being able to present it in an illuminating manner, such that the rest of the class can also come away with the same sort of intuition of how the theorem works and how it is useful. Any help would be greatly appreciated.  EDIT: I should point out that the formulation of the theorem we are being tasked to prove is the following:  Let $\lbrace a_n \rbrace$, $\lbrace b_n \rbrace$ be sequences, ${b_n}$ strictly increasing and unbounded. Then if $\lim\limits_{n \to \infty} \frac {a_{n+1} - a_n}{b_{n+1} - b_n} = l$ for some $l \in \mathbb R$, then $\lim\limits_{n \to \infty} \frac{a_n}{b_n} = l$ also. Zorn's Lemma states that if every chain $C$ in a partially ordered set $X$ has an upper bound then there is at least one maximal element in $X$.  Let $n\in \mathbb{N}$, $C_n \subset \mathbb{N}$ be the set containing the natural numbers $\{1,\dots,n\}$. Then if $k\le n$, $C_k\subset C_n$, so $C_n$ is a chain. Also, $C_n$ has an upper bound, such as $n+1$. But what is the maximal element of $\mathbb{N}$?  There's something I don't get in Zorn's Lemma statement. TL:DR: Is it ever a good idea to train an ML model on all the data available before shipping it to production? Put another way, is it ever ok to train on all data available and not check if the model overfits, or get a final read of the expected performance of the model?    Say I have a family of models parametrized by $\alpha$. I can do a search (e.g. a grid search) on $\alpha$ by, for example, running k-fold cross-validation for each candidate.   The point of using cross-validation for choosing $\alpha$ is that I can check if a learned model $\beta_i$ for that particular $\alpha_i$ had e.g. overfit, by testing it on the "unseen data" in each CV iteration (a validation set). After iterating through all $\alpha_i$'s, I could then choose a model $\beta_{\alpha^*}$ learned for the parameters $\alpha^*$ that seemed to do best on the grid search, e.g. on average across all folds.  Now, say that after model selection I would like to use all the the data that I have available in an attempt to ship the best possible model in production.  For this, I could use the parameters $\alpha^*$ that I chose via grid search with cross-validation, and then, after training the model on the full ($F$) dataset, I would a get a single new learned model $\beta^{F}_{\alpha^*}$   The problem is that, if I use my entire dataset for training,  I can't reliably check if this new learned model $\beta^{F}_{\alpha^*}$ overfits or how it may perform on unseen data. So is this at all good practice? What is a good way to think about this problem? Using Squeeze Theorem to show the following limits Consider a function f (x) defined on R satisfying:   for all x distinct 0.  Calculate: lim f(x) with x→∞ and limf(x) with x→−∞   Issue information:   if x → ∞ then we can consider | x | = x  if x → -∞ then we can consider | x | = -x  I can use x² = | x |? I have county data in which the &quot;FIP&quot;s (actually State &quot;FIP&quot;s and County &quot;FIP&quot;s combined). I have data imported as CSV with the sames &quot;FIP&quot;s data titled 'STCounty'. However, the shapefile &quot;FIP&quot;s is listed as a Real and the CSV came in as an Integer and the Join function does not seem to work.  The drop boxes are greyed out/empty. So the bigger questions is how do you change the attribute type in a table? I tried to create a new column in the shapefile (county data) and set it to an integer and then multiply the &quot;FIP&quot;s*1, but got a column full of NULL. I am new to QGIS and have a lot of experience in MapInfo, so the join concept is not new to me, just the syntax in QGIS. Is there a program to mount all of my drives automatically? I'd like to typeset documents using the '' of page layout. Good examples are on pages 40-53 of . The  package is helpful for this, but two additional features would be useful:   Automatic flow of text across (arbitrarily placed) columns / textpos blocks. Vertical line spacing enforced to be an integer multiple of a base line spacing, even when interrupted (for example) by an equation of arbitrary height.   Any ideas as to how either or both of these could be accomplished? Origin of the term "fun fact" Where does the term "fun fact" originate?-- namely, not with the compositional meaning but rather with the idiomatic usage to introduce some sort of unusual, esoteric, absurd or otherwise "controversial" fact?