Talk:3015: D&D Combinatorics

2024-11-23T01:14:59Z

172.71.147.206: Calculate the odds,please

The bot originally created this page as “D Combinatorics”. I renamed it to the correct title and tried to get as many of the references as possible (including a few redirects). [[User:JBYoshi|JBYoshi]] ([[User talk:JBYoshi|talk]]) 00:54, 23 November 2024 (UTC)

What are the odds of rolling 16 or higher on 3D6+D4? 3D6 average 10.5, D4 average is 2.5, total average should be 13. I do not know how to proceed from here.

3010: Geometriphylogenetics

2024-11-12T04:57:22Z

172.71.147.206:

{{comic
| number = 3010
| date = November 11, 2024
| title = Geometriphylogenetics
| image = geometriphylogenetics_2x.png
| imagesize = 316x391px
| noexpand = true
| titletext = There's a maximum likelihood that I'm doing phylogenetics wrong.
}}

==Explanation==
{{incomplete|Created by A EUCLIDIAN GENOME - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

{{w|Phylogenetics}} refers to the practice of examining relationships among things that follow the principle of "descent with modification of progeny". In the course of descent with modification, one thing may give rise to two (the progeny), different modifications happen to each, and those modifications become established. Iterated "splits" over time yield a tree of objects; it is the purpose of phylogenetics to recover ("reconstruct") these trees, and use the information gained to inform study of the things contained. Phylogenetics has been most commonly applied to the classification/taxonomy of biological species and investigations of their evolutionary history, but it has also been used to examine the evolution of genes and biosynthetic pathways, and in the study of human languages and their evolution. Data for phylogenetic analyses may come from any attributes ("characters") of the things being examined; {{w|Computational_phylogenetics|rigorous techniques}} for these analysis became available starting in the {{w|Willi_Hennig|1950s}}. In phylogenetic studies of organisms, their DNA is far and away the most data-dense source of information, and consequently, most present-day investigations are based on analyses of selected genes and, increasingly, whole genomes. It is commonplace for such studies, especially on relatively understudied creatures, to reconstruct an evolutionary history (a phylogeny) that is radically different from what had previously been assumed.

This comic presents a tree, which purports to be a phylogenetic tree and resembles one, in which the endpoints ("terminal taxa") are geometric shapes, hence "geometriphylogenetics", a portmanteau of "{{w|geometry}}" and "phylogenetics". The claim, that triangles are more closely related to circles and ellipses than to squares, rectangles, pentangles, and the like, is a riff on the findings, and even the wording, of authentic phylogenetic research papers. The absurdity, and the joke, is that geometries do not change over time via descent with modification of progeny, therefore phylogenetic principles and techniques are inapplicable to their study. Moreover, geometries do not contain DNA, so genetic analysis, even if relevant, is impossible.

The title text alludes to {{w|Computational_phylogenetics#Maximum_likelihood|maximum likelihood}}, one of the most robust, and most frequently used, methodologies for phylogenetic analysis. The method builds a number of trees from the data, assigns to each a probability that it conforms to a pre-selected model of evolution, and then selects the tree that has the highest likelihood of conformity to the model. The key to the joke is that maximum likelihood is a probabilistic method; "there is a high probability that I'm doing phylogenetics wrong". Which is, in fact, the case.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[A tree diagram, or a dendrogram is shown, consisting of lines that branch off from left to right, starting with one horizontal line on the left. Eight results are shown on the right: ellipse on Path 1, circle on Path 2, triangle on Path 3, parallelogram on Path 4, trapezoid on Path 5, square on Path 6, rectangle on Path 7, and a pentagon on Path 8. The paths are listed in order top to bottom.]
:[Path 3 and the triangle are bold black, while the other branches are dimmer. The paths are connected as follows: Path 2 and 3 are connected, then both connect together to Path 1; Path 4 and 5 are connected, as are Path 6 and 7, and these two paths are connected altogether; Path 8 is then connected to the branch containing Paths 4 to 7. All of Paths 1 to 3 are then connected to Paths 4 to 8, the branches all culminating in a single line on the left.]

:[Caption below the panel:]
:The phylogenetic revolution continues:
:Triangles were long believed to be related to squares, but genetic analysis proves that they are actually very pointy circles.

{{comic discussion}}

[[Category:Geometry]]
[[Category:Biology]]
[[Category:Charts]]
[[Category:Statistics]]

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Talk:3015: D&D Combinatorics

3010: Geometriphylogenetics