Useful tips for everyday
Why is Poisson distribution used? In statistics, a Poisson distribution is a probability distribution that is used to show how many times an event is…
What does it mean to take the expectation? noun. the act or the state of expecting: to wait in expectation. the act or state of…
How is variance calculated in PCA? The total variance is the sum of variances of all individual principal components. The fraction of variance explained by…
What is multivariate normal imputation? Multivariate normal imputation MVNI is a joint modelling approach to imputation where all variables in the imputation model are assumed…
What is an isotropic Gaussian? TLDR: An isotropic gaussian is one where the covariance matrix is represented by the simplified matrix Σ=σ2I. Some motivations: Consider…
What does it mean when someone makes a statistical inference? Statistical inference is the process of drawing conclusions about an underlying population based on a…
What is exposure in Poisson regression? Poisson models handle exposure variables by using simple algebra to change the dependent variable from a rate into a…
What is a significant R-squared change value? SPSS prints something called the R-square change, which is just the improvement in R-square when the second predictor…
Why do we use placebos in research? Researchers use placebos during studies to help them understand what effect a new drug or some other treatment…
What is mini meta-analysis? Furthermore, even with a small number of studies one can compare them (or subgroups of them) to each other. The goal…