Brown Bag Seminar - Alfred Lehar

30/06/2020

We are pleased to announce the upcoming Brown Bag seminar on June 30th, 2020.

Given the current situation, we move the Brown Bag Seminars to Microsoft Teams.

The next Brown Bag Seminar is scheduled for Tuesday, June 30th, 2020, 18:00-19:00 via MS Teams. The meeting will open at 17:45 for you to dial in. To join the stream please follow this link.

Our speaker will be Alfred Lehar (University of Calgary).

He will give a talk on "Miner Collusion and the BitCoin Protocol".

Abstract: Bitcoin users can offer fees to miners who record their transactions in the block-chain. We document high variation of bitcoin fees, not only over time, but also within blocks. Further, the block-chain rarely runs at capacity, even though fees tend to be higher when blocks are fuller, so miners appear to be leaving `money on the table.' We present a simple model of price discrimination to explain our results. We note that mining pools facilitate collusive equilibria, and estimate that they have extracted least 200 million USD a year in excess fees by making processing capacity scarce.

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Name	Purpose	Lifetime	Provider
CookieConsent	Saves your consent to using cookies.	30 days	WU
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_hjAbsoluteSessionInProgress	Used to detect the first pageview session of a user.	30 minutes	Hotjar
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Name	Purpose	Lifetime	Provider
test_cookie	Is set as a test to check whether the browser allows cookies to be set. Does not contain any identification features.	15 minute	Google
IDE	Contains a randomly generated user ID. Using this ID, Google can recognize the user across different websites across domains and display personalized advertising.	1 year	Google
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fr	Used to serve advertisements and measure and improve their relevance.	90 day	Facebook
m_pixel_ratio	Performance cookie used by Facebook with Facebook pixels.	session	Facebook
wd	Used for analysis purposes. Technical parameters are logged (e.g. aspect ratio and dimensions of the screen) so that Facebook apps can be displayed correctly.	7 day	Facebook
dpr	Used for analysis purposes. Technical parameters are logged (e.g. aspect ratio and dimensions of the screen) so that Facebook apps can be displayed correctly.	7 day	Facebook
sb	Used to save browser details and Facebook account security information.	2 year	Facebook
dbln	Used to save browser details and Facebook account security information.	2 year	Facebook
spin	Cookie for advertising purposes and reporting on social campaigns.	session	Facebook
presence	Contains the "Chat" status of a logged in user.	1 month	Facebook
x-referer	Performance cookie that is used by Facebook in combination with Facebook pixels.	session	Facebook
cppo	Cookie for statistical purposes.	90 day	Facebook
datr	Identifies the browser for security and website integrity purposes, including account recovery and identification of potentially compromised accounts.	2 year	Facebook
locale	Saves language settings.	session	Facebook
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aam_uuid	This cookie is used for ID synchronization with Adobe Audience Manager.	30 days	LinkedIn
AMCV_XXX_at_AdobeOrg	This cookie contains a unique identifier for the Adobe Experience Cloud.	180 days	LinkedIn
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lang	This cookie stores the language settings of a user. This ensures that the LinkedIn.com website appears in the language selected by the user.	session	LinkedIn
twll	This cookie is set when X is embedded on the page. X collects data that is mainly used for tracking and targeting.	4 year	X
secure_session	This cookie is set when X is embedded on the page. E.g. X's like or sharing functions.	14 year	X
guest_id	This cookie is set by X when a visitor shares content from the WU website on X.	2 year	X
personalization_id	This cookie is set by X to measure the performance of X advertising campaigns in a user's browsers and devices	2 year	X
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auth_token	This cookie is required for authentication and checks whether the user is logged in.	10 months	X
external_referer	This cookie collects statistical data, including how often you visit X and how long a user stays on X.	1 day	X
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CONSENT	This cookie is used to support Google's advertising services.	20 year	YouTube
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Brown Bag Seminar - Alfred Lehar

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