predic+ons • Nope. Users want decision, or engagement – Data mining will reveal “the truth” about SE • [Dejaeger: TSE’11], [Hall: TSE’12], [Shepperd:COW’13] • Not(BeXer learners = beXer conclusions)
predic+ons • Nope. Users want decision, or engagement – Data mining will reveal “the truth” about SE • [Dejaeger: TSE’11], [Hall: TSE’12], [Shepperd:COW’13] • Not(BeXer learners = beXer conclusions) – Sooner or later: enough data for general conclusions • Found more differences than generali+es • Special issues: [IST’13], [ESEj’13] • Best papers, ASE’11, MSR’12 • Menzies, Zimmermann et al [TSE’13] • Lots of local models
what is true about the data – Not trivia on how algorithms walk that data • Map the landscape – Reason on each part of map • E.g. landscape mining – Unsupervised itera+ve dichotomiza+on – Cluster, prune – Then generate rules 5
what is true about the data – Not trivia on how algorithms walk that data • Map the landscape – Reason on each part of map • E.g. landscape mining – Unsupervised itera+ve dichotomiza+on – Cluster, prune – Then generate rules • Different to “leap before you look” – i.e. skew learning by class variable – then study the results • E.g. C4.5, CART, Fayya-‐Iranni, etc – Supervised itera+ve dichotomiza+on • E.g. 61% * 300+effort es+ma+on papers – Algorithm +nkering, without end 6
that is not limited to a specific set of values but varies in a con+nuum. • Groups together a broad range of condi+ons or behaviors under one single +tle • In mathema+cs, the spectrum of a (finite-‐dimensional) matrix is the set of its eigenvalues. • Nystrom algorithms: approxima+ons to eigenvalues – FASTMAP: linear +me
– 400+ examples – 20 centroids • Predic+on via: – Extrapola+on between two nearest centroids • Works as well as – Random forest, Naïve Bayes • For defect predic+on (10 data sets) – Linear regression, M5’ • For effort es+ma+on (10 data sets)
decision mining 3. discussion mining yesterday today tomorrow future Beyond Data Mining, T. Menzies, IEEE So6ware, 2013, to appear 13 Q: why call it mining? • A1: because all the primi+ves for the above are in the data mining literature • So we know how to get from here to there • A2: because data mining scales