Problem 44286. Compute average gain for some bets.

Created by Michelangelo Ricciulli

Solve Later

{"relationships":[{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/document","targetMode":"","relationshipId":"rId1","target":"/matlab/document.xml"},{"relationshipType":"http://schemas.mathworks.com/matlab/code/2013/relationships/output","targetMode":"","relationshipId":"rId2","target":"/matlab/output.xml"}],"parts":[{"partUri":"/matlab/document.xml","relationship":[],"contentType":"application/vnd.mathworks.matlab.code.document+xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<w:document xmlns:w=\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\"><w:body><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Given a vector containg the odds of some events in decimal format (e.g.,</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:rFonts w:cs=\"monospace\"/></w:rPr><w:t>odds=[1.3 2.5 1.5]</w:t></w:r><w:r><w:t> ) and a vector of the same dimensions containing the amount of dollars that you are betting for each of those (e.g.,</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:rFonts w:cs=\"monospace\"/></w:rPr><w:t>bets=[100 10 80]</w:t></w:r><w:r><w:t> ), the function</w:t></w:r><w:r><w:t> </w:t></w:r><w:r><w:rPr><w:rFonts w:cs=\"monospace\"/></w:rPr><w:t>avg_gain(odds,bets)</w:t></w:r><w:r><w:t> should return the average of the gain for each possible outcome. The average is a simple average and should not weight the events by their actual probability. Moreover it needs to be rounded to the second decimal digit.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Example: odds= [1.1] bets= [100]</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>there are only two possible outcomes in this simple case:</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"ListParagraph\"/><w:numPr><w:numId w:val=\"2\"/></w:numPr></w:pPr><w:r><w:t>Item one I win the bet: I gain 100*1.1 -100 dollars= +10 dollars</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"ListParagraph\"/><w:numPr><w:numId w:val=\"2\"/></w:numPr></w:pPr><w:r><w:t>Item two I lose the bet: I just lose the bet of 100 dollars = -100 dollars.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>So I need to perform an average of -100 and 10 that is -45.</w:t></w:r></w:p><w:p><w:pPr><w:pStyle w:val=\"text\"/></w:pPr><w:r><w:t>Disclaimer: a positive average does not mean that betting is a good idea, since we are only performing a simple average, ignoring the probabilities of the different events. I want in no way encourage betting since it is risky and sometimes addictive. It's just a simple Cody problem, take it for what it really is.</w:t></w:r></w:p></w:body></w:document>"},{"partUri":"/matlab/output.xml","contentType":"text/xml","content":"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?><embeddedOutputs><metaData><evaluationState>manual</evaluationState><layoutState>code</layoutState><outputStatus>ready</outputStatus></metaData><outputArray type=\"array\"/><regionArray type=\"array\"/></embeddedOutputs>"}]}

Given a vector containg the odds of some events in decimal format (e.g., <tt>odds=[1.3 2.5 1.5]</tt> ) and a vector of the same dimensions containing the amount of dollars that you are betting for each of those (e.g., <tt>bets=[100 10 80]</tt> ), the function <tt>avg_gain(odds,bets)</tt> should return the average of the gain for each possible outcome. The average is a simple average and should not weight the events by their actual probability. Moreover it needs to be rounded to the second decimal digit.Example:
odds= [1.1]
bets= [100]there are only two possible outcomes in this simple case:<ol><li>Item one I win the bet: I gain 100*1.1 -100 dollars= +10 dollars</li><li>Item two I lose the bet: I just lose the bet of 100 dollars = -100 dollars.</li></ol>So I need to perform an average of -100 and 10 that is -45.Disclaimer: a positive average does not mean that betting is a good idea, since we are only performing a simple average, ignoring the probabilities of the different events. I want in no way encourage betting since it is risky and sometimes addictive. It's just a simple Cody problem, take it for what it really is.

Solve

Solution Stats

55 Solutions
20 Solvers

Last Solution submitted on Dec 30, 2020

Last 200 Solutions

Problem Comments

3 Comments

3 Comments

Rafael Hernandez-Walls on 12 Aug 2017

????

David Verrelli on 13 Dec 2017

Please revise problem statement to indicate that summation is required, such as:
"the function avg_gain(odds,bets) should return the SUM of each bet's average gain (averaged for each possible outcome)"
It is not obvious from the example.

Rafael S.T. Vieira on 12 Oct 2020

As stated by David, it is required to sum the averages after the calculation.

Problem Recent Solvers20

Problem Tags

betting loss average odds odds

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!