Questions tagged [ancova]
Analysis of Covariance. This is really a special case of multiple linear regression, used in ANOVA-like settings with some continuous covariates in addition to the categorical ones.
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Repeated measures analysis of covariance literature
Does anyone have a literature to study about repeated measures ANCOVA?
For example, the concept, assumption, and how to calculate manually?
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Overall ANCOVA not significant but post-hoc pairwise comparison are
I have the following problem:
I run a ANCOVA with three time-points and 3 covariates; no factors (groups).
My overall ANCOVA is not significant. But all my post-hoc (Bonferroni-adjusted) pairwise ...
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Ancova or other test?
I am struggling to select the correct type of test for my data and would like to eventually run it in R. The design is as follows:
A treatment vs control group of plants
From each plant the following ...
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Logistic regression for experimental inference?
I'm curious if logistic regression is appropriate when the task is inferring a treatment effect on proportions (ex: success rate) when covariates are present and some imbalance across treatment and ...
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Mixed ANCOVA Assumptions
I have a Mixed ANCOVA. my within-subjects factor is Time [Pre- and post-intervention) and my between-subjects factor is Group [4 intervention]). My IVs are group and time. My DV is happiness, which is ...
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Explain ANCOVA to a newbie
I'm currently doing a statistical analysis between the effect of diversity and population density on depression in different counties across the US. I have currently run a two way ANOVA test and I ...
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Observational pre post design and confounder adjustment
I have observational data with baseline, and two follow-up measures with a binary treatment. Dependant variable is questionnaire scale score ***. I am planning on fitting a linear mixed effects model ...
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Difference between an ANCOVA and an ANOVA on residuals that the effects of covariates are already removed
My psychological experiment has a repeated-measures design. Each participant performed 4 conditions (Factor A [2 levels] X Factor B [2 levels]). Let say the DV is the accuracy of the participants and ...
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Mixed Effects with repeated measures design and covariate included
I have a dataset that consists of the oxygen consumption (MO2) values for 3 different species of fish. My experiment was a repeated measures design where I measured MO2 of the same 14 fish per species ...
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Power analysis for ANCOVA
I'm interested in conducting power analysis for experiment design and inference using ANCOVA. I see questions A,B,C vary in terms of quality, applicably and answers; whereas I'm interested in an ...
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Can you assess Moderation with ANCOVA?
I am using SPSS for analysis with 1 group IV (4 levels), one DV measured at time 1 and time 2 for each participant in each group, and one covariate measured once at time 2 or for each participant in ...
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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 ...
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ANCOVA main ideas [duplicate]
Is Analysis of Covariance just OLS regression plus a hypothesis test on top of predicted y-values?
$\hat{y} = BX = B_{treatment}treatment + X_{2...n}B_{2...n}+B_0$
$H_0: \mu_{\hat{y}_{treatment}} - \...
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In a 2 arm pre-post RCT, is an interaction test on an ANOVA the same as a t-test of the change scores?
Say you have a 2-armed pre-test post-test control trial design. You want to test the effect of group allocation on the outcome variable. I simulated a version of this in R, using 3 different methods: ...
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Comparison of 2 groups with covariate
I compared 2 groups and found that their test scores are significantly different. However, I also found that they are significantly different in the mean age. I want to see if the scores between the ...
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