bootstrap

1. Bootstrap with binary data

Hi All, I kind of stuck on where to start for bootstrap with binary data. So, I have big numbers of data that consists an acrivity within area. The data will represent just like does the activity is success of failure, represent by 1 for success and 0 for failure. Example: in area A, we got...
2. Why does bootstraping with 50% samplesize and no replacements always gives appropriate confidence intervals.

Hello, I compared different ways to calculate confidence intervals. On the one side I used the direct formular on the other side I used a percentile bootstrap methoden. (Calculate the statistic (e. g. mean) on n subsamples and choose the a/2 and 1-a/2 percentile for the confidence interval.) I...
3. Doubt with random numbers in parametric Bootstrap

Hello all, Suppose I have a set of datas 8...20, with mean 10 and lambda 1/10=0.1 . I want to make a parametric bootstrap, supousing my datas come from an exponential distribution. So now I may construct my random samples from an exponential distribution with lambda=0.1 . My problem is I do...
4. Need help to correctly bootstrap confidence interval for correlation of 50 y-values against 50 averages from autocorrelated subsets of 2000 x-values

I am helping out with some plots for a paper: simple X versus Y plots, and would like to provide some stats to improve the paper. My statistics knowledge is rusty and I am an R-noob with only a few weeks of Tidyverse under my belt, so I would appreciate some input. Am I on the right track? The...
5. P values from bootstrap in R

I've been trying to get the pvalue of my samples from a bootstrap rsquared test in R. I'm not very good with statistics so could someone please take a look at my below code and point me in the right direction with regards to how I can extract the p-values per sample (basically input a...
6. Extracting p value from bootstrap

I've been trying to get the pvalue of my samples from a bootstrap rsquared test in R. I'm not very good with statistics so could someone please take a look at my below code and point me in the right direction with regards to how I can extract the p-values per sample (basically input a...
7. Getting p-value for rsquared bootstrap in R

I've been trying to get the pvalue of my samples from a bootstrap rsquared test in R. I'm not very good with statistics so could someone please take a look at my below code and point me in the right direction with regards to how I can extract the p-values per sample? # Bootstrap 95% CI for...
8. Bootstrapping with sample(), what should the size of your sub-sample be?

Hi I am currently bootstrapping my sample, x, using the sample function. sample(x, size = n, replace = T) My question is how do you know what size should be? Is there a standard procedure in determining the value of size?
9. How to continue raw data for Forcasting ~ Holts-Winter

Hi All, I am new to this forum and i am in need of help regarding the Holt's Winter Method. I've managed to build a forecasting model in excel using the Damped method which works very well. But due to my lack of experience, I am confused on how to continue the raw data as the forecasting...
10. Bootstrapping and Independent T Tests

Dear all, My question is whether it is appropriate to use Independent T Tests on distributions generated through bootstrapping. To be more specific: I used bootstrapping to generate 1000 subsamples for each of two observed distributions from different samples. I then used an SPSS macro to...
11. Unbalanced designs in PERMANOVA and Resampling Methods

Dear all, I am a new member here, working mainly in Ecology. I hope this is the right section to ask my question. I am dealing with unbalanced designs (I am comparing groups with different sample sizes) in PERMANOVA (Permutational Multivariate Analysis of Variance). The PERMANOVA runs...
12. Unbalanced designs in PERMANOVA and Resampling Methods

Dear all, I am a new member and I have to say I am not sure if this is the right section for my question (I am working in ecology). I am dealing with unbalanced designs (I am comparing groups with different sample sizes) in PERMANOVA (Permutational Multivariate Analysis of Variance). The...
13. Bootstrap and hypothesis test

Hi, I have to decide whether two groups have the same variance or not. My sample size is less then impressive, 13 data points per group. I ran Bartletts test and got a p-value of 0.09 - but I suspected that the relatively high value might be due to the small sample size. So, I ran a...
14. Bootstrapping 0.632+ AUC with fixed test sets

Hi, I want to compare different binary classifiers in terms of their AUC values on test sets. I have data over one year with about 2000 observations each month. Now I would like to use the data in each of the last three months as separate test sets while using the months prior to a...
15. The bootstrap method for medical modelling

I am part of a team creating a model for paediatric hospitalised patients and would appreciate some help. We are looking to produce an accurate model for weight estimation, using input variables of gender, age and mid-upper arm circumference. This would be helpful as some children arrive in...
16. How to Fit polynomial regression by bootstrap and establishing IC of each parameters

#Hi everybody and excuse me for my bad english for this request on R. #here parameter of an hypothetical interval : x=c(60,59,55,49,43,38,33,28,24,20,17,15,12,10,8,6,5) y=c(59,55,49,43,38,33,28,24,20,17,15,12,10,8,6,5,4) #I adjusted it by a polynomial regression degree 3 (not the best...
17. Bootstrap procedure to test difference between correlation coefficients

Hi everyone, I have two correlation coefficients (r1 and r2), obtained within the same sample (20 subjects). My aim is to test it they are significantly different. r1 is the correlation between a neurophysiological parameter and a behavioural parameter in condition A; r2 is the correlation...
18. How to merge two data sets with varying date intervals?

I'm sure this problem isn't unique. I have two sets of data, both \$ values and I want to add them together and plot them on a chart. The problem is that one data set is quarterly and the other is daily but I want to display the resulting set (the addition of the two data sets) in weekly or...
19. Bootstrap strange estimate

Hello everyone, I'm a statistical novice, I would like your help. I'm analyzing non-normally distributed variables. To develop the confidence interval I preferred to use non-parametric method: bootstrap. Unfortunately I get output biased estimates and standard errors high, even though I used a...
20. Bootstrapping code help needed in r??

Hello friends. So I am ready to jump off a building because I cannot figure out this code for my LIFE. Everytime I run it, I get the standard error of 0 (bias=0 too) so obviously I'm doing something wrong because it's using the same sample when I want 1000 iterations. I want the AIC of the...