Recent content by Rabolisk

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    Maximizing problem with an inequality constraint.

    Hello I have a worked example where I have to maximize a function with an inequality constraint. The problem is worked out below. https://zgqqmw.sn2.livefilestore.com/y1pLc13HVWpA9dATZEzikySeSMBN2hn1mJCw71rJ5vvUJcr9W7KBPFkOz7HQEppa6EPbLi5yyAwDagh3ezF_7eyVL6tBK7q6ise/maxProbem.png?psid=1 I...
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    Having trouble understanding sources of hetroscedasticity

    Hey. Iam trying to understand how specification of the equation can lead to hetroscedasticity. This is stright out of my notes. Yt=B1+B2x2t+B3x3t+...+BkXkt+\gamma\varpi+ε^{}_{t} Yt=B1+B2x2t+B3x3t+...+Bkxkt+ε^{*}_{t} where ε^{*}_{t} = εt + \gamma\varpit Since Var(εt) =...
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    Having trouble understaning the notation co-variances

    Can someone explain to me how Cov(x,y)=[X-E(x))(Y-E(y)] and this would equal 0 under the normal OLS assumption. I know how to calculate the covariance, but X here is a matrix. So I don't understand the logic of this formula...
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    How to proove that that e^x is convex

    Homework Statement I have to determine if [e][/x] is a convex function. If it is then show proof. I know its a convex function by looking at the graph, Iam stuck at prooving it mathematically though. Homework Equations The function is f(x)=e^x. The Attempt at a Solution I am...
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    Anyone know how to tell which USB ports are Hi speed?

    If you plug in a high speed device your pc should say if its not a high speed one. If it says nothing then it is high speed.
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