Assume a survey plot that shows a histogram of percentages of respondent's answers, like the following which shows "Percentages of respondents' answers for five tornado warning behaviors across six lead time and daylight scenarios": Do error bars make any sense for a plot like that? As far as I know, error bars are useful only … Read more
I have an example of call center data for 2013. There are 261 days of data (excluding weekends). For 2013, I have included a holiday dummy variable (holiday) for the days where there were no stats. For 2014, I have also included a future holiday dummy variable (holidayf). My objective is to assess how accurate … Read more
When working with an LSTM network in Keras. The first layer has the input_shape parameter show below. model.add(LSTM(50, input_shape=(window_size, num_features), return_sequences=True)) I don't quite follow the window size parameter and the effect it will have on the model. As far as I understand, to make a decision the network not only makes use of current … Read more
I am interested in finding the mean and standard deviation of the whole distribution by looking only at a random sample. I don't know anything else about the distribution (for example I don't know if the distribution is normal or not). Is what I'm asking even possible? Best Answer Sure, your best guess of the … Read more
I've attached a picture of the time series I'm talking about. The top is the original series, the bottom is the differenced series. Each data point is a 5 minute average reading from a strain gauge. This strain gauge is placed on a machine. The noisy areas correspond to areas where the machine is turned … Read more
I am developing an artificial model to simulate the growth of two types of biological cells under different conditions. The data I obtained from my model takes the form of two data-sets representing the number of cells in the culture across time in what we will call condition A and conditon B. Ie: A = … Read more
I've used the confint() function of R package metafor to calculate heterogeneity in random effects models in a meta-analysis. I get sensible values for the various parameters (tau, tau^2, I^2) for most of the calculations I have run, however am getting back 0 values for all three parameters for one particular analysis. I have checked … Read more
Why are the number on a ball in a lotto draw categorical nominal instead of categorical ordinal? Don't the numbers have a natural ascending order and would thus be ordinal? Or am I making an incorrect assumption about numbers having a natural order? Best Answer You could color-code the balls without fundamentally changing the game. … Read more
Both Root Mean Square and Average absolute deviation seem like the measures of the magnitude of variability (especially when the variates are both +ve and -ve). What are the rules of thumb to choose one of them over the other? Best Answer In theory, this should be determined by how important different sized errors are … Read more
From Artificial Intelligence: A modern approach: Most nonparametric models have the advantage that it is easy to do leave-one-out crossvalidation without having to recompute everything. With a k-nearest-neighbors model, for instance, when given a test example (x, y) we retrieve the k nearest neighbors once, compute the per-example loss L(y, h(x)) from them, and record … Read more