{
localUrl: '../page/prior_probability.html',
arbitalUrl: 'https://arbital.com/p/prior_probability',
rawJsonUrl: '../raw/1rm.json',
likeableId: '705',
likeableType: 'page',
myLikeValue: '0',
likeCount: '2',
dislikeCount: '0',
likeScore: '2',
individualLikes: [
'EricBruylant',
'JeanneLai'
],
pageId: 'prior_probability',
edit: '17',
editSummary: '',
prevEdit: '16',
currentEdit: '17',
wasPublished: 'true',
type: 'wiki',
title: 'Prior probability',
clickbait: 'What we believed before seeing the evidence.',
textLength: '1659',
alias: 'prior_probability',
externalUrl: '',
sortChildrenBy: 'likes',
hasVote: 'false',
voteType: '',
votesAnonymous: 'false',
editCreatorId: 'EricBruylant',
editCreatedAt: '2016-08-04 14:27:46',
pageCreatorId: 'EliezerYudkowsky',
pageCreatedAt: '2016-01-27 04:55:27',
seeDomainId: '0',
editDomainId: 'AlexeiAndreev',
submitToDomainId: '0',
isAutosave: 'false',
isSnapshot: 'false',
isLiveEdit: 'true',
isMinorEdit: 'false',
indirectTeacher: 'false',
todoCount: '0',
isEditorComment: 'false',
isApprovedComment: 'true',
isResolved: 'false',
snapshotText: '',
anchorContext: '',
anchorText: '',
anchorOffset: '0',
mergedInto: '',
isDeleted: 'false',
viewCount: '313',
text: '"Prior [1rf probability]", "prior [1rb odds]", or just "prior" refers to a state of belief that obtained before seeing a piece of new evidence. Suppose there are two suspects in a murder, Colonel Mustard and Miss Scarlet. After determining that the victim was poisoned, you think Mustard and Scarlet are respectively 25% and 75% likely to have committed the murder. *Before* determining that the victim was poisoned, perhaps, you thought Mustard and Scarlet were equally likely to have committed the murder (50% and 50%). In this case, your "prior probability" of Miss Scarlet committing the murder was 50%, and your "posterior probability" after seeing the evidence was 75%.\n\nThe prior probability of a hypothesis $H$ is often being written with the unconditioned notation $\\mathbb P(H)$, while the posterior after seeing the evidence $e$ is often being denoted by the [1rj conditional probability] $\\mathbb P(H\\mid e).$%%note: [E. T. Jaynes](http://bayes.wustl.edu/) was known to insist on using the explicit notation $\\mathbb P (H\\mid I_0)$ to denote the prior probability of $H$, with $I_0$ denoting the prior, and never trying to write any entirely unconditional probability $\\mathbb P(X)$. Since, said Jaynes, we always have *some* prior information.%% %%knows-requisite([1r6]): This however is a heuristic rather than a law, and might be false inside some complicated problems. If we've already seen $e_0$ and are now updating on $e_1$, then in this new problem the new prior will be $\\mathbb P(H\\mid e_0)$ and the new posterior will be $\\mathbb P(H\\mid e_1 \\wedge e_0).$ %%\n\nFor questions about how priors are "ultimately" determined, see [11w].',
metaText: '',
isTextLoaded: 'true',
isSubscribedToDiscussion: 'false',
isSubscribedToUser: 'false',
isSubscribedAsMaintainer: 'false',
discussionSubscriberCount: '1',
maintainerCount: '1',
userSubscriberCount: '0',
lastVisit: '2016-02-13 14:22:24',
hasDraft: 'false',
votes: [],
voteSummary: [
'0',
'0',
'0',
'0',
'0',
'0',
'0',
'0',
'0',
'0'
],
muVoteSummary: '0',
voteScaling: '0',
currentUserVote: '-2',
voteCount: '0',
lockedVoteType: '',
maxEditEver: '0',
redLinkCount: '0',
lockedBy: '',
lockedUntil: '',
nextPageId: '',
prevPageId: '',
usedAsMastery: 'false',
proposalEditNum: '0',
permissions: {
edit: {
has: 'false',
reason: 'You don't have domain permission to edit this page'
},
proposeEdit: {
has: 'true',
reason: ''
},
delete: {
has: 'false',
reason: 'You don't have domain permission to delete this page'
},
comment: {
has: 'false',
reason: 'You can't comment in this domain because you are not a member'
},
proposeComment: {
has: 'true',
reason: ''
}
},
summaries: {
Summary: '"Prior [1rf probability]", "prior [1rb odds]", or just "prior" refers to a state of belief that obtained before seeing a piece of new evidence. Suppose there are two suspects in a murder, Colonel Mustard and Miss Scarlet. After determining that the victim was poisoned, you think Mustard and Scarlet are respectively 25% and 75% likely to have committed the murder. *Before* determining that the victim was poisoned, perhaps, you thought Mustard and Scarlet were equally likely to have committed the murder (50% and 50%). In this case, your "prior probability" of Miss Scarlet committing the murder was 50%, and your "posterior probability" after seeing the evidence was 75%.'
},
creatorIds: [
'EliezerYudkowsky',
'EricBruylant',
'NateSoares'
],
childIds: [],
parentIds: [
'bayes_reasoning'
],
commentIds: [],
questionIds: [],
tagIds: [
'needs_summary_meta_tag'
],
relatedIds: [],
markIds: [],
explanations: [
{
id: '5861',
parentId: 'prior_probability',
childId: 'prior_probability',
type: 'subject',
creatorId: 'AlexeiAndreev',
createdAt: '2016-08-02 17:34:30',
level: '1',
isStrong: 'true',
everPublished: 'true'
}
],
learnMore: [],
requirements: [
{
id: '5862',
parentId: 'conditional_probability',
childId: 'prior_probability',
type: 'requirement',
creatorId: 'AlexeiAndreev',
createdAt: '2016-08-02 17:34:49',
level: '2',
isStrong: 'false',
everPublished: 'true'
}
],
subjects: [
{
id: '5861',
parentId: 'prior_probability',
childId: 'prior_probability',
type: 'subject',
creatorId: 'AlexeiAndreev',
createdAt: '2016-08-02 17:34:30',
level: '1',
isStrong: 'true',
everPublished: 'true'
}
],
lenses: [],
lensParentId: '',
pathPages: [],
learnMoreTaughtMap: {},
learnMoreCoveredMap: {},
learnMoreRequiredMap: {},
editHistory: {},
domainSubmissions: {},
answers: [],
answerCount: '0',
commentCount: '0',
newCommentCount: '0',
linkedMarkCount: '0',
changeLogs: [
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18356',
pageId: 'prior_probability',
userId: 'EricBruylant',
edit: '17',
type: 'newEdit',
createdAt: '2016-08-04 14:27:46',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18355',
pageId: 'prior_probability',
userId: 'EricBruylant',
edit: '16',
type: 'newEdit',
createdAt: '2016-08-04 14:26:21',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18354',
pageId: 'prior_probability',
userId: 'EricBruylant',
edit: '15',
type: 'newEdit',
createdAt: '2016-08-04 14:24:58',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: 'moved note to note'
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18186',
pageId: 'prior_probability',
userId: 'EricBruylant',
edit: '0',
type: 'newTag',
createdAt: '2016-08-02 18:26:18',
auxPageId: 'needs_summary_meta_tag',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18164',
pageId: 'prior_probability',
userId: 'AlexeiAndreev',
edit: '0',
type: 'newRequirement',
createdAt: '2016-08-02 17:34:50',
auxPageId: 'conditional_probability',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18162',
pageId: 'prior_probability',
userId: 'AlexeiAndreev',
edit: '0',
type: 'newTeacher',
createdAt: '2016-08-02 17:34:31',
auxPageId: 'prior_probability',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '18163',
pageId: 'prior_probability',
userId: 'AlexeiAndreev',
edit: '0',
type: 'newSubject',
createdAt: '2016-08-02 17:34:31',
auxPageId: 'prior_probability',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '16189',
pageId: 'prior_probability',
userId: 'NateSoares',
edit: '14',
type: 'newEdit',
createdAt: '2016-07-08 15:38:16',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5825',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '12',
type: 'newEdit',
createdAt: '2016-01-27 05:26:35',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5812',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '11',
type: 'newEdit',
createdAt: '2016-01-27 05:12:40',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5811',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '10',
type: 'newEdit',
createdAt: '2016-01-27 05:11:09',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5810',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '9',
type: 'newEdit',
createdAt: '2016-01-27 05:10:11',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5809',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '8',
type: 'newEdit',
createdAt: '2016-01-27 05:09:25',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5808',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '7',
type: 'newEdit',
createdAt: '2016-01-27 05:08:41',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5807',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '6',
type: 'newEdit',
createdAt: '2016-01-27 05:07:53',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5806',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '5',
type: 'newEdit',
createdAt: '2016-01-27 05:07:20',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5805',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '4',
type: 'newEdit',
createdAt: '2016-01-27 05:06:48',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5804',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '3',
type: 'newEdit',
createdAt: '2016-01-27 05:06:18',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5803',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '2',
type: 'newEdit',
createdAt: '2016-01-27 05:00:50',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5802',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '1',
type: 'newEdit',
createdAt: '2016-01-27 04:55:27',
auxPageId: '',
oldSettingsValue: '',
newSettingsValue: ''
},
{
likeableId: '0',
likeableType: 'changeLog',
myLikeValue: '0',
likeCount: '0',
dislikeCount: '0',
likeScore: '0',
individualLikes: [],
id: '5801',
pageId: 'prior_probability',
userId: 'EliezerYudkowsky',
edit: '0',
type: 'newParent',
createdAt: '2016-01-27 04:49:03',
auxPageId: 'bayes_reasoning',
oldSettingsValue: '',
newSettingsValue: ''
}
],
feedSubmissions: [],
searchStrings: {},
hasChildren: 'false',
hasParents: 'true',
redAliases: {},
improvementTagIds: [],
nonMetaTagIds: [],
todos: [],
slowDownMap: 'null',
speedUpMap: 'null',
arcPageIds: 'null',
contentRequests: {}
}