Quadratic Covariation of an Increasing Process with another Process is 0












0












$begingroup$


According to the book I'm reading on Option Pricing:




Since $V$ is an increasing process, $langle X, V rangle_t = langle V rangle_t = 0$




In this case $X$ is just a price process (according to the book the specific form shouldn't matter, but the process is assumed to be a continuous local martingale)



Does anyone see why this is true? Are there specific conditions under which it is true, or is it just for any increasing process?



I found a similar unanswered question, but wanted to try again: Quadratic Variation of Increasing Process?



Thanks a lot!










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  • $begingroup$
    The quadratic covariation of an increasing process with a continuous process is zero. That's a general statement which is not very difficult to show using the very definition of the quadratic covariation.
    $endgroup$
    – saz
    Jan 30 at 7:23










  • $begingroup$
    Cross-posted: quant.stackexchange.com/questions/43789/…
    $endgroup$
    – LocalVolatility
    Jan 30 at 7:43
















0












$begingroup$


According to the book I'm reading on Option Pricing:




Since $V$ is an increasing process, $langle X, V rangle_t = langle V rangle_t = 0$




In this case $X$ is just a price process (according to the book the specific form shouldn't matter, but the process is assumed to be a continuous local martingale)



Does anyone see why this is true? Are there specific conditions under which it is true, or is it just for any increasing process?



I found a similar unanswered question, but wanted to try again: Quadratic Variation of Increasing Process?



Thanks a lot!










share|cite|improve this question









$endgroup$












  • $begingroup$
    The quadratic covariation of an increasing process with a continuous process is zero. That's a general statement which is not very difficult to show using the very definition of the quadratic covariation.
    $endgroup$
    – saz
    Jan 30 at 7:23










  • $begingroup$
    Cross-posted: quant.stackexchange.com/questions/43789/…
    $endgroup$
    – LocalVolatility
    Jan 30 at 7:43














0












0








0





$begingroup$


According to the book I'm reading on Option Pricing:




Since $V$ is an increasing process, $langle X, V rangle_t = langle V rangle_t = 0$




In this case $X$ is just a price process (according to the book the specific form shouldn't matter, but the process is assumed to be a continuous local martingale)



Does anyone see why this is true? Are there specific conditions under which it is true, or is it just for any increasing process?



I found a similar unanswered question, but wanted to try again: Quadratic Variation of Increasing Process?



Thanks a lot!










share|cite|improve this question









$endgroup$




According to the book I'm reading on Option Pricing:




Since $V$ is an increasing process, $langle X, V rangle_t = langle V rangle_t = 0$




In this case $X$ is just a price process (according to the book the specific form shouldn't matter, but the process is assumed to be a continuous local martingale)



Does anyone see why this is true? Are there specific conditions under which it is true, or is it just for any increasing process?



I found a similar unanswered question, but wanted to try again: Quadratic Variation of Increasing Process?



Thanks a lot!







stochastic-processes stochastic-calculus martingales






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Jan 29 at 23:30









SladeSlade

59111




59111












  • $begingroup$
    The quadratic covariation of an increasing process with a continuous process is zero. That's a general statement which is not very difficult to show using the very definition of the quadratic covariation.
    $endgroup$
    – saz
    Jan 30 at 7:23










  • $begingroup$
    Cross-posted: quant.stackexchange.com/questions/43789/…
    $endgroup$
    – LocalVolatility
    Jan 30 at 7:43


















  • $begingroup$
    The quadratic covariation of an increasing process with a continuous process is zero. That's a general statement which is not very difficult to show using the very definition of the quadratic covariation.
    $endgroup$
    – saz
    Jan 30 at 7:23










  • $begingroup$
    Cross-posted: quant.stackexchange.com/questions/43789/…
    $endgroup$
    – LocalVolatility
    Jan 30 at 7:43
















$begingroup$
The quadratic covariation of an increasing process with a continuous process is zero. That's a general statement which is not very difficult to show using the very definition of the quadratic covariation.
$endgroup$
– saz
Jan 30 at 7:23




$begingroup$
The quadratic covariation of an increasing process with a continuous process is zero. That's a general statement which is not very difficult to show using the very definition of the quadratic covariation.
$endgroup$
– saz
Jan 30 at 7:23












$begingroup$
Cross-posted: quant.stackexchange.com/questions/43789/…
$endgroup$
– LocalVolatility
Jan 30 at 7:43




$begingroup$
Cross-posted: quant.stackexchange.com/questions/43789/…
$endgroup$
– LocalVolatility
Jan 30 at 7:43










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