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PST: Error in names(StCol) <- A : attempt to set an attribute on NULL

Consider the following code: library(PST) library(TraMineR) library(RCurl) x <- getURL("https://gist.githubusercontent.com/aronlindberg/c79be941bc86274f4526705600962789/raw/...
histelheim's user avatar
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1 vote
2 answers
69 views

When does PST display contexts from left to right and right to left?

Does the PST package always display contexts from right to left? In the query() function we use a string to represent a context. If I'm assuming that the context is specified from right to left (as ...
histelheim's user avatar
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1 vote
1 answer
651 views

How to test if two lift values are significantly different from each other?

Consider this code: # Load libraries library(RCurl) library(TraMineR) library(PST) # Get data x <- getURL("https://gist.githubusercontent.com/aronlindberg/08228977353bf6dc2edb3ec121f54a29/raw/...
histelheim's user avatar
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1 vote
0 answers
45 views

Comparing log-loss values for a probabilistic suffix tree?

In the PST package one can estimate the prediction quality of individual sequences using the log-loss, e.g: R> ex2 <- c("a-a-b", "a-b-a-a-b", "b-b-b-b-a") R> ex2 <- seqdef(ex2) R> ...
histelheim's user avatar
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1 vote
1 answer
86 views

Meaning of lag parameter in PST?

In the pmine() function in PST you can use lags. What is this lag? Does it mean that it ignores the lag first positions in the sequence? Or does it mean that you allow for lags within the subsequences?...
histelheim's user avatar
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1 vote
1 answer
55 views

What is the meaning of alpha in the context of an information gain pruning function?

In the PST package we use the value C as a cut-off for the information gain function used to prune the tree. The C value, for an alpha of 0.05 is calculated as follows: C95 <- qchisq(0.95, 1) / 2 ...
histelheim's user avatar
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2 votes
1 answer
98 views

Predicting conditional probabilities based on contexts with only 1 state

It seems that PST cannot predict the conditional probabilities of the next state after contexts which consist of a single state, e.g. EX-EX Consider this code: # Load libraries library(RCurl) ...
histelheim's user avatar
  • 5,018
2 votes
1 answer
57 views

Calculate lift for context-state relationship in a probabilistic suffix tree?

PST gives me probabilities and conditional probabilities for various contexts and following states. However, it would be very helpful to be able to calculate the lift (and its significance) of the ...
histelheim's user avatar
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2 votes
1 answer
273 views

Where in the sequence of a Probabilistic Suffix Tree does "e" occur?

In my data there are only missing data (*) on the right side of the sequences. That means that no sequence starts with * and no sequence has any other markers after *. Despite this the PST (...
histelheim's user avatar
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2 votes
2 answers
107 views

Getting log-likelihood from probabilistic suffix tree

Here is my code: library(RCurl) library(TraMineR) library(PST) x <- getURL("https://gist.githubusercontent.com/aronlindberg/08228977353bf6dc2edb3ec121f54a29/raw/...
histelheim's user avatar
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