Skip to main content

Questions tagged [group-differences]

Group differences broadly refer to statistics which quantify the differences between two or more subpopulations.

Filter by
Sorted by
Tagged with
5 votes
3 answers
188 views

ANOVA with unreliable measure

I’m doing some literature review on sports science, in particular the effect of training on endurance. There is no standard endurance tests. Some consist in intermittent contractions until exhaustion ...
Experience111's user avatar
0 votes
0 answers
20 views

test for differences in empirical cumulative distribution functions between groups

What test could I use to test for differences in empirical cumulative distribution functions between two or more groups? Note that I am not looking for a test two compare two ecdf (Kolmogorov–Smirnov ...
ucfaard's user avatar
  • 43
0 votes
1 answer
17 views

Measurement invariance across groups and time

I want to run a multi-group longitudinal model. Based on prior invariance testing, I can assume scalar invariance across groups and time. So is it appropriate to have both the same intercepts across ...
JoMo's user avatar
  • 1
1 vote
1 answer
37 views

How to find difference between two hazard ratios (ratio of hazard ratios)

I am reading a meta-analysis and in this paper the authors somehow compared HR from two groups with different treatments in each study. As I know, we can compare outcomes from two groups with ...
reress's user avatar
  • 11
2 votes
1 answer
54 views

What is the best t-test to compare two groups with a confounding factor and unequal sample size in each group?

I am working on my master thesis and came up with a problem. I want to validate if changing the raw material for a chemical reaction would give the same yield of my product of interest. First, I did ...
JorgeTheChemist's user avatar
3 votes
2 answers
172 views

Fitting multiple linear regression models to select molecules for which a feature of interest significantly alters concentration

I'm using data from a proteomics platform called Olink. In this case, the data comes from samples of 16 patients and 16 controls. The patients can be further classified into 2 subgroups. The assay ...
maglorismyspiritanimal's user avatar
0 votes
0 answers
21 views

How to properly compare a single diagnostic test in two subpopulations

Suppose I have a diagnostic test with a binary response. I have performed this test on some population. Now, I split this population in two subgroups (e.g. male/female), and would like to check if ...
Alb's user avatar
  • 115
0 votes
0 answers
56 views

gene total volume test

1, I want to compare the FGF gene total expression level (sum level from all the cells) in two groups of cells. Suppose group A has 500 cells and group B has 100 cells. 2, gene FGF level in the two ...
coding_something's user avatar
1 vote
1 answer
26 views

Appropriate Research Design for Multiple Independent Variables and Dependent Variables

I need some advice on designing the quantitative aspect of my upcoming master's research project. My research design involves a convergent mixed methods study and aims to explore the factors that ...
Domus's user avatar
  • 11
1 vote
1 answer
34 views

How to analyze between-group differences in within-group variances over time in a 3-level model?

The data I am using is collected within the physical fitness surveillance program in schools. In these schools, either no intervention, healthy lifestyle intervention, healthy schools network ...
Antonio Martinko's user avatar
2 votes
0 answers
43 views

Standardization of summary statistic of group-linked values

Assume that you measure a summary statistic (e.g., arithmetic mean) in measurement windows of a fixed size along a long sequence of values and that these values are grouped into regions belonging to ...
Michael Gruenstaeudl's user avatar
2 votes
2 answers
78 views

ANCOVA or MODERATION?

I'm struggling with the statistics for a question I'm collecting data to answer. My paper is about whether different meditation types can increase happiness when controlling for meaning in life. There ...
Johnny A's user avatar
3 votes
1 answer
37 views

Group comparison with multiple group memberships

I want to statistically compare personality scores between different groups, but people can be in multiple groups. Is there anything problematic in just doing an ANOVA or a t-test since a respondent ...
Tim's user avatar
  • 77
1 vote
1 answer
13 views

Transforming data with two groups for multiple regression analysis

I have a dataset includes 2 groups (HC, PT) and unfortunately, variables (8) are not normal. I'm trying to run a multiple regression to see if the relationship between the variable of interest ("...
statnoob9's user avatar
0 votes
0 answers
10 views

Variability of patients in different Hospitals

just to let you know that my statistical background is not very good. I made funnel graphs which shows the effect of polypharmacy against practice size. In the funnel graphs, a dot presents a single ...
Usman YousafZai's user avatar
0 votes
1 answer
45 views

What is the difference between a one sample t test of the difference between two groups versus a two sample t test comparing the two groups?

Let us say that we currently have two independent groups $G_1, G_2$ with equal sample numbers $n_{G_1} = n_{G_2}$ and may not have equal variances $ {\sigma_1}^2 \neq {\sigma_2}^2$. If the statistical ...
Syuma's user avatar
  • 125
0 votes
0 answers
15 views

How to compare frequencies of type of stress events with repeated measurements over time in a weekly diary study?

We hope you can help clarify whether a Chi-square test of equal frequencies (in SPSS) would be the correct choice. Study participants have reported experienced stress events (text variable) in a ...
Andi04's user avatar
  • 1
0 votes
1 answer
44 views

Data analysis for school project

I have to create a hypothetical study focusing on the relationship between sBCMA (soluble B-cell maturation antigen in blood) and the expression of BCMA on bone marrow cells in patients with multiple ...
youknow 321's user avatar
6 votes
1 answer
224 views

Best statistical approach for determining a significant cutoff value?

Assume a study comparing fingernail length to incidence of fungal infection. Ultimately, the goal is to determine a maximum length to propose for use by animal care takers. One proposed approach: 1st ...
theforestecologist's user avatar
0 votes
0 answers
16 views

How to calculate bias having three groups?

Three groups of people each tried one of the three different applications and answered a questionnaire on a Likert scale from 0 to 4. Their age and experience in video games were also asked (on a ...
Micaela Yanet Martin's user avatar
0 votes
0 answers
38 views

Which test do I need for testing differences in two populations?

I would like to compare the different variables in a life table of two populations and check if the differences are significant. However, I am totally unsure which test is appropriate. For example, I ...
Octtta's user avatar
  • 1
0 votes
0 answers
14 views

DiD with multiple overlapping windows

I would like to set up a difference in difference model with multiple overlapping windows. The treatment group are firms located in a county hit by a hurricane while the control group includes all ...
jeopardyss96's user avatar
1 vote
1 answer
46 views

Is there a meaningful way to 'quantify' a group representative partition of its network when subjects within group have their own unique partitions?

I currently have a dataset which can be split into two groups: disease vs control. Each group consists of $n_{disease}$ and $n_{control}$ subjects respectively. The dataset itself is a correlation ...
Syuma's user avatar
  • 125
1 vote
1 answer
43 views

Identifying an outlier nominal group different than the norm, based on an ordinal dependent variable

As part of my graduate thesis, I've measured the satisfaction levels of a couple hundred respondents across 7 districts of a city about a local public service, using a 4-point ordinal Likert scale (...
ToastedHambugerBun's user avatar
0 votes
0 answers
17 views

What is a good measure of the effect size of group difference in a multigroup multilevel model?

Consider that you have a multilevel model measuring students' mathematics knowledge. The students are nested within classes, and classes are nested within schools. Additionally, we want to examine the ...
J. Doe's user avatar
  • 357
3 votes
1 answer
65 views

Can I aggregate several continuous variables into percentages and then compare those percentages between groups?

I have a dataset with the concentrations of several lipids. I'm interested in finding lipids that are altered between two conditions, but the lipids are not indepentent from each other and the ...
maglorismyspiritanimal's user avatar
2 votes
2 answers
205 views

How do I interpret low subgroup interaction and high efficacy in only one group?

I have read several articles concerning subgroup interaction interpretation but none of them have the situation I am dealing with. Suppose we have an experiment with a control vs treatment influence ...
Boris Smirnov's user avatar
0 votes
0 answers
33 views

Is it valid to use unsupervised clustering to assign patients into larger groups before comparing them to controls?

I have very high-dimensional data (lipidomics) with two categories: patient/control and genetic mutation. These mutations have similar phenotypes, but they are considered different diseases. Their ...
maglorismyspiritanimal's user avatar
0 votes
1 answer
57 views

what book should I read to learn inferential statistics? [closed]

I am not a statistics student so I have no clue about inferential statistics. All I learned was descriptive stats. I am currently conducting research to find if two groups are similar/not. I have ...
Zel's user avatar
  • 9
4 votes
1 answer
27 views

How to code for a mulitgroup analysis concerning two catagorical variables

I have a question on syntax for Mplus. I am running a multivariate latent growth curve with 7 repeated measures, variables X and Y (diagram attached). I also have two grouping variables, sex and ...
EmH's user avatar
  • 315
0 votes
0 answers
36 views

Effective pairwise comparisons for group ranking?

Suppose I have a list of items(~3500 in number) and I want to do a group based ranking into 4-5 groups. I can get pairwise comparisons between the elements but I want to choose the items to compare in ...
something something's user avatar
0 votes
0 answers
28 views

Which test would I use in this situation?

I have a sample of people, $n=300$. All $300$ should be offered both of two therapeutic treatments (Treatment A and B). I will be collecting data on how many people were offered A only, B only, and A ...
Josh Sewell's user avatar
0 votes
0 answers
5 views

Comparing the pattern of commensal of two drugs over time

I would naturally appreciate your advice on the following problem: Following operations, patients can be started either Drug A or Drug B to prevent blood clots forming in patients calves. We surveyed $...
Naren's user avatar
  • 1
2 votes
0 answers
44 views

One-way repeated measures ANOVA with skewed response

We have an experiment with 102 individuals in total. We have an outcome $Y$ (which is a variable related to the structure of a given bone), and we want to know whether this variable $Y$ differs ...
Leandro T.'s user avatar
5 votes
1 answer
102 views

Performing a Difference-in-Difference Analysis where the Control Group is Already Treated

I'm involved in a project where the outcome is the proportion of cancer patients who have received surgery. The treatment event is a state-level policy change that mandated moving all these cancer ...
user8408275's user avatar
0 votes
1 answer
55 views

Comparing two groups by the counts of their features

Imagine there are two different groups of individual samples. I know they are different but I don't know why. For example in biology a group of sick individuals and a group of healthy ones. Now for ...
lesolorzanov's user avatar
2 votes
0 answers
32 views

A covariate as an inherent part of predictor

I want to compare brain volumes of two disease categories: young vs. old onset. I know that age, in general, is a covariate for brain volume. That is, the older the age, the smaller the brain. However,...
user23253590's user avatar
0 votes
0 answers
8 views

Handling Informative Censored Data in Comparative Analysis of Cumulative Outcomes Across Groups

Hello Cross Validated community, I am working on a dataset that involves multiple groups undergoing a series of interventions, with the aim to achieve a binary outcome (e.g., success or failure). The ...
insan's user avatar
  • 145
1 vote
0 answers
33 views

Statistical Comparison of Continuous Outcomes Across Groups with Identical Observations

Cross Validated community, I am working with a dataset of restaurants that have been classified by both Michelin and Rafaelo rating systems. Specifically, Michelin has categorized restaurants into A, ...
insan's user avatar
  • 145
0 votes
0 answers
10 views

Calculating and displaying variation of sub group responses within larger group

I have a question with 3 possible answers (yes, no, unsure), and I have the responses of two groups. Group A and group B. Group A has three sub-groups (A1, A2, A3), Group B has two sub-groups (B1, B2) ...
Dave's user avatar
  • 1
2 votes
1 answer
86 views

Is Multiple Comparison Correction necessary for multiple ANCOVA tests

I'm working on fMRI data comparing brain activation from ten different brain areas across three groups after controlling for covariates such as age, sex, disease severity. I built an ANCOVA model with ...
SStt1002's user avatar
6 votes
2 answers
350 views

Using a t-test to test effect size

In my line of work, I work with large data and often run stat tests to compare differences between groups. The problem I am facing is that if I use a $t$-test to measure any difference, the result ...
baz's user avatar
  • 61
8 votes
1 answer
74 views

MLM / HLM Equal sample sizes needed between groups?

I am working on analyzing a dataset from a diary study (6–14 repeated measures per participant). The sample I have consists of 2 groups (1 with expertise, 1 without) that are thought to differ on many ...
r-ks's user avatar
  • 113
0 votes
0 answers
34 views

What test do I use when comparing multiple dependent groups that are non-parametric?

Basically, I am comparing outcomes in a variable that applies to everyone in a field to each subcategory of the group (e.g., average annual pay for all nurses versus annual pay for all of the ...
A Sani's user avatar
  • 1
0 votes
0 answers
11 views

Significance test to compare groups when a variable has multiple occurences per case

I'm finishing a manuscript, but have one nagging problem which I'm unable to find an answer. Study has two groups which receive different procedure for a disease. After the procedure, one patient may ...
Lauri Pautola's user avatar
0 votes
0 answers
7 views

Is it appropriate to conduct a Kruskal-Wallis test with the mean of a 3 item construct measured on a 7-point Likert scale as independent variable?

I am working on my master's thesis and conducted two studies. The first study utilizes 3 groups. The problem is, that the group sizes are very small (n1 = 13, n2 = 14, n3 = 14). I want to test if ...
Tom's user avatar
  • 1
0 votes
0 answers
12 views

what is the equivalent of manova for pretest postest data for paired groups?

how can i test for differences in pretest and posttest of anxiety and aggressive behavior in regards to the experimental group only? noting that i have already conducted a MANOVA and found statistical ...
afifa bendj's user avatar
1 vote
0 answers
55 views

Analysis of the difference between two groups on multiple outcomes

My question contains a few variations; I apologize for this in advance. I have two groups, and I have four outcome measures. These outcome measures are assessments of pain, function, depression level, ...
Ertan's user avatar
  • 41
0 votes
0 answers
11 views

Is it meaningful to compare within-group AUROC between groups?

I have a risk model that I want to evaluate on different (patient) groups in order to compare how well the model is working on each of them. The groups may differ in size, baseline / prevalence / ...
Eike P.'s user avatar
  • 3,118
6 votes
3 answers
234 views

Are post-hoc adjusted analyses more valid than initial analyses?

Many papers design a methodology to detect a difference between $2$ groups regarding a primary outcome. This result is then given a $p$ value to denote statistical significance. Some papers then go on ...
user356816's user avatar

1
2 3 4 5
14