Recent content by leejayd

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    Symmetrical matrix

    Hi, I have a vector representing distances between cities. I have an nxn matrix looking like : Manchester Leeds London Manchester Leeds London I'm trying to get the distances loaded to the matrix but I only have distances in one direction so I need to...
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    Reshaping data

    Hi, I have a data frame which looks like : Jan_V Jan_S Feb_V Feb_S 1 100 90 120 110 2 123 88 112 120 3 121 89 134 130 There are around 200 rows. The data frame can have additional month columns i.e. Mar_V...
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    Time series question

    Hi, If I have a time series that has a normal distribution of error from the mean is there a technique that lets me forecast the next period based a stronger weighting for recent months. I suppose I can work it up but wondered if anything exists. Thanks in advance.
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    Heteroscedastic variables with linear regression

    Hi, I'm a stat beginner and learning about linear regression. Regarding heteroscedastic variables (i.e. variables with different levels of residuals throughout the population). I can identify them by looking at the scatter or plotting residuals. A couple of questions I have are...
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    Strange behaviour with Cbind

    Hi, I'm trying to reshape data and as part of this I have a data object containing a data frame that can have multiple pairs of XY columns and around 400 rows of numbers. I need to run a function for each pair of XY columns. Eventually I'm looking to loop through the frame and extract...
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    Determine furthest points on an ellipsoid for charting purposes

    Hi, I'm trying to plot an ellipsoid chart with the code below : library(cluster) x <- rnorm(150) y <- rnorm(150) + 2*x + 10) xy <- unname(cbind(x, y) exy <- ellipsoidhull(xy) maxx <- max(xy[,1])*3 maxy <- max(xy[,2])*3 minx <- min(xy[,1])/3 miny <- min(xy[,2])/3 plot(xy...
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    Ellipse chart in R - extend axis

    Hi, I'm using the code below to create an ellipses chart (using the Cluster package). It works well except the ellipses hull can extend beyond the x&y axis. Is there a way to extend the axis to ensure the ellipse hull doesn't fall outside the axis? I've tried playing with xaxs but it...
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    Ellipse chart in R

    Hi, I have a data frame with the following : Sales Team|Appointments #|Closed Sales #|Month For a given month I would like to create the following chart type : Imagine a scatter chart plotting Appointments on the X and and Closed Sales on the Y for each Sales Team. Now imagine an...
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    Help for beginner - forecasting events

    Hi, I'm looking for general pointers regarding forecasting events. We have a process where sales of services are made. These sales go through a lengthy admin and approval process. I'm looking to predict how many approved sales will complete the process in the current month. I have a table of...