I have a standard code for ggplot2 which I use to make line graphs, scatter plots, and histograms. For lines or scatters: p<- ggplot(x, aes(x=Year, y=Rank, colour=Uni, group=Uni)) #colour lines by variable Uni #group Uni labelled variables in the same line Then: p + #you get an error if not for this step geom_line(size=1.2) + […]
Recently someone asked: “I don’t suppose you’d like to blog a little on the pedagogical knowledge relevant to statistics teaching, would you? A ‘top five statistics student misconceptions (and what to do about them)’ would be kind of a nice … Continue reading →
In a paper arXived on Friday, Roberto Fontana relates the generation of Sudoku grids to the one of Latin squares (which is unsurprising) and to maximum cliques of a graph (more surprising). The generation of a random Latin square proceeds in three steps: generate a random Latin square L with identity permutation matrix on symbol […]
Wednesday, in class, we’ve seen how to visualize a multiple regression model (with two continuous explanatory variables). Here, the goal is to predict the average cost of an insurance claim, using some covariates, e.g. the age of the driver, and the age of the car (recall that losses here are liability losses). The prediction obtained from a (standard) generalized linear model, with a log-link > reg1=glm(cout~ageconducteur+agevehicule,data=base,family=Gamma(link="log")) The code to visualize…
Patterns, vocab and practice, practice, practice An important part of statistical analysis is being able to look at graphical representation of data, extract meaning and make comments about it, particularly related to the context. Graph interpretation is a difficult skill … Continue reading →
Statistics is about story-telling. For people who understand them, graphs tell a story. To the initiated, even a p-value, and some summary statistics can help to tell a story. Part of the role of a statistician is to extract the … Continue reading →
I often hear this question: Should I use Excel to teach my class? Or should I use R? Which package is the best? It depends on the class The short answer is: It depends on your class. You have to … Continue reading →
In the strictest sense, APA style discourages the use of color in graphics, stipulating that it be used only when it is "absolutely necessary". Consequently, most universities and dissertation committees also discourage (or downright forbid) the use of...
Depending on where you land in the political spectrum you may either love or despise Fox News. But regardless of your political affiliation, you have to recognize that their statisticians are well-trained in the art of using graphics to persuade … Continue reading →
