8-Chems

SLIM · GL-SLIM · EASE — Conceptual Comparison Recommender Systems · Item-Item Models · Conceptual Analysis SLIM, GL-SLIM & EASE A conceptual comparison of three item-item collaborative filtering models — how they think about the same problem differently Abstract All three models answer the same question: given a user's interaction history, which items should we recommend? They all do it by learning an item-item weight matrix W such that a user's predicted preference vector is X·W . Yet they arrive at radically different solutions — one iterates with gradient descent over thousands of steps, one solves a single linear system in seconds, and one sits between both worlds by adding group-aware local models on top. Understanding why they differ is more useful than memorising their equations. §1 The Shared Foundation Every model in this family makes the same fundamental assumption:...

Android Layouts – Deep Dive Reference Android Layouts — Deep Dive Side-by-side XML & UI · Attributes · Examples · When to use each LinearLayout RelativeLayout ConstraintLayout FrameLayout TableLayout ScrollView GridLayout ⬇️ LinearLayout android.widget.LinearLayout The simplest layout. All children are arranged in a single direction — either vertical (top→bottom) or horizontal (left→right). Each child follows the next in sequence. You can use layout_weight to distribute space proportionally. ✓ Simple & fast ✓ Predictable ✓ Supports weight ✗ No overlap ✗ Deep nesting = slow Best for: forms, toolbars, lists // Key Attributes android:orientation "vertical" | "horizontal" Direction children are stacked. Default is horizontal. ...