How can I model a prediction of a dependent variable using BOTH a predictor at time 1, time 2 AND the change (time 2-1) of this predictor?

I want to model the following: DV: Y at time 3 IVs: X at time 1, X at time 2, change of X from time 1 to time 2 Which is the most appropriate way (preferably in SPSS). I am afraid I cannot use...

10 December 2020 264 3 View

Can you recommend me tree databases?

Hi. I have slight experience in searching phylogenetic trees, normaly I use TreeBASE or Dryad but some papers that I found doesn't have the resulting trees in these databases or there are genetic...

26 October 2020 582 3 View

Could ANOVAs be used as a substitute for regression models for mediation analysis?

Hello all, I hope you can help me with these questions. I am developing a mediation analysis using the mediation package in R. I need to analyze the influence of perceived learning (Mediating...

18 August 2020 7,521 9 View

What would be the fate of ecotoxicology in the South American studies?

I'm currently working on ecotoxicology and I'd like to know what my colleagues from the same area think, especially in South America. Too much of microplastics in my opinion, but few studies...

18 May 2020 1,064 2 View

(epidemiology) how does one measure the RATE of infectivity?

I am not an epidemiologist, nor am I studying epidemiology, this is a question born of sheer curiosity due to current events. I understand (more or less) the principle behind the basic...

19 March 2020 9,458 3 View

How can I clean insect exoskeleton?

I want to remove whole soft tissues and maintain intact the exoeskeleton

10 March 2020 4,345 6 View

How would you evaluate "Interpersonal Trust" for people who are sharing a 4-seat vehicle with people they do not know?

Hi. I am conducting an experiment and I would like to understand if people would be willing to share a 4-seat vehicle with people they do not know. I have thought that the personal tendency of...

10 December 2019 7,989 3 View

How to handle output data for Taguchi DOE?

I am using a L8 (2 level, 4 Factor) DOE. I have completed the experiments and am now trying to sift through the data and start the analysis. I completed these experiments in a strictly production...

03 December 2019 1,977 5 View

PDL1 expression in PB lymphocytes by flow cytometry?

is there anyone who study PDL1expression in PB lymphocytes by flow cytometry in healthy controls and in pathological cases ( cancer) Oddly, we found that healthy controls express more PDL1 than...

02 December 2019 4,873 3 View

How can i measure health well-being ?

12 August 2019 8,050 3 View

How optimize the Size Exclusion Chromatography?

Hello! I'll do a size exclusion chromatography, but I only have an open column, and I'll perform the peptide extraction from yeast, using buffer lysis (sodium phosphate 50 mM/NaCl 30 mM/DNAse and...

01 March 2021 2,215 2 View

No title

01 March 2021 3,905 5 View

What test should I use to compare two or three means, if data is not normally distributed but sample size is > 30 in each group?

I personally feel this as a most confusing question. As per my understanding, if sample size is > 30, and sample is skewed, we can still use paramteric approach, as it will follow Z...

01 March 2021 1,587 6 View

Is it necessary to report effect size (ES) in statistics of biomedical research given that we already report p values routinely?

Pls share your thoughts

01 March 2021 7,330 4 View

Why there are two peaks while using the mie plot of Silver nanoparticle?

Hi, I am trying to learn the theoretical modelling of silver nanoparticle using the Mie scattering theory. After that, I discovered a software named Mieplot developed by Philip Laven, where it...

25 February 2021 7,493 6 View

How to calculate Z (the number of molecules in a unit cell) for calculating theoretical density?

I am trying to calculate the theoretical density of my ceramics materials. I use the formula below to calculate the theoretical density: Theoretical density = (Molecular weight x No. of molecules...

24 February 2021 3,823 2 View

How to handle studies which report perfect effect sizes in a meta-analysis using Pearson's r?

I'm in the process of updating a meta-analysis and in one of the new studies, effect sizes are reported as Tau-U. Two of the effect sizes are reported as Tau-U = 1.00. I am using Andy Field's...

24 February 2021 2,265 3 View

Sample size determination for non-parametric tests?

How do I run a a priori sample size determination for non-parametric tests, like the Mann-Whitney U-test and the Kruskall-Wallis or other non-parametric tests that accord with the unpaired t-test...

24 February 2021 166 6 View

How to determine a priori sample size for t-test with unequal means?

I need to conduct a a priori sample size determinations for t-test with unequal means, but I don't know the sizes of the groups nor the ratio of both groups... Can I do a sample size determination...

24 February 2021 8,289 3 View

What are alternatives to factor analysis for a small sample?

My sample size is too small to conduct a factor analysis. I created my own psychometric scale for measuring Effectiveness of Support, which contains 38 items (4 sub-scales) Im really struggling...

23 February 2021 9,287 12 View