# Questions tagged [statistics]

For questions about statistical methods that might be appropriate for certain paradigms within psychology, psychiatry, neuroscience, or cognitive science.

130 questions
3k views

### When is it defendable to use manifest instead of latent variables in psychological research?

In psychology, most of the concepts, theories, ideas etc. of interest refer to latent variables, where a latent variable is one that can't be observed directly. Instead, one has to find a manifest ...
121 views

### How is sample size determined in animal research?

In human research, we define our universe and estimate the effect size we expect to observe, then we can draw the a sample of a given size. How is sample size determined for experiments in the animal ...
399 views

### Where can I find a longitudinal study with a binary response?

I've spent the last couple of months trying to find real data (not simulated) of a longitudinal study, but I can't seem to find one. Any topic and time frame is fine, but the dependent variable must ...
206 views

### Do we need a pre-test to compare the effectiveness of two treatments?

Assume, I want to evaluate how effective two teachers are in teaching English to German children. Both teachers have been teaching at the same high school for twenty years, and both use a distinctly ...
74 views

### How many samples are there when test subjects come through different recruitment strategies?

Let's assume I want to conduct a survey. To find test subjects, I post an ad in a local newspaper, one on a locally relevant website, distribute flyers in front of the train station, and have managed ...
123 views

### How to analyse 3 by 3 design with Likert scale ratings?

I want to understand what would be the best way to analyze the results of an online likert-scale ratings of pictures on 3 dimensions. I have 3 groups of participants from different countries. They are ...
119 views

### Are there any models of the human visual field of view taking into account head, neck and eye movements and calculating likelihood of fixation?

I would like to know if there are studies that (1) model the field of view taking into account all degrees of freedom of the head, neck and eyes and (2) if there is any probabilistic model assigned to ...
40 views

### How to identify participants answering online questionnaires who have not paid attention? [duplicate]

I often analyse data that involves participants completing a selection of psychological tests online. A concern with online testing is that some participants may not complete the task conscientiously. ...
553 views

### How to interpret HLM analyses looking at work group and individual worker effects?

Liden et al (2004, PDF) is an example of a study examining employees in work groups in an organisation. Thus, measures are obtained of both individual workers and of the work groups that they belong ...
489 views

### Facet versus scale prediction of Big 5 personality

NEO facets and scales: The NEO model of personality has 5 scales (i.e., extraversion, neuroticism, agreeableness, openness, and conscientiousness). For each scale there are 6 facets (e.g., neuroticism ...
672 views

### How to estimate an expected effect size for a planned psychology study?

When planning a psychological study, researchers are often asked to formulate an estimate of expected effect sizes for important hypotheses in the study. This might be the expected group mean ...
122 views

### Are cortisol measures more reliable than self-reported fear measures for looking at difference scores?

I was sent an email by a researcher with the following question: You wrote that difference scores are okay to use if measurement error is minimised. Does that imply that biological data ...
5k views

### How to compute Chi-square value and degrees of freedom in Excel?

I am trying to understand the statistical test of the chi-square in Excel. I already made the test but I still don't know how to compute the χ² value and what it means, how to compute the degrees of ...
1k views

### How to adjust SSE or RMSE for the number of free parameters in the model?

How do I adjust SSE (sum of squared errors) or RMSE (root-mean-square errors) for the number of free parameters in the model? Is there an "adjusted" RMSD metric similar to the adjusted r-squared ...
400 views

### Best practice to handle double negatives when using the expectancy-value model?

My question is regarding the multiplicative combination rule in the Expectancy-value model developed by Fishbein and Ajzen, and the issues regarding the expectancy value-muddle, or the case of "double ...
107 views

### Are there any standard psychometric scales that are only applicable to within-subject designs?

A while ago, I asked the question whether Presence questionnaires are valid in between-subject designs (see the question for the background to this assumption). While the question garnered some ...
364 views

### Analysis of parameter estimates from Ratcliff diffusion model

I would like to analyze a dataset in which subjects' reaction time and error rate have been recorded. In order to account for potential speed-accuracy trade-off I am planning to make use of the ...
134 views

### Reproducible meta-analysis in psychology

I am a big proponent of reproducible data analysis. In particular, I like when researchers share documents in formats like Sweave and knitr which weave statistical output (e.g., text, tables, and ...
253 views

### Controlling for response bias in a forced choice memory task

I want to present participants a pair of items $a$ and $b$, each with an association $x$ or $y$. Later on participants will presented with the items singularly, and asked 'what was the association?'. ...
51 views

### Is it reasonable to have a factor with only two levels in a carry-over design for an fMRI study?

I'm planning a carry-over design for an fMRI study. To save time, since it seems that I'll need a huge number of trials for my purpose, I'm wondering if it's reasonable to have a matrix 2x3x3, ...
1k views

### What articles use structural equation modelling in a meta-analytic context to model mediation?

I'm interested in structural equation modelling (SEM) meta-analysis and its application to modelling mediation relationships. Mike W.-L. Cheung has written a few articles on the topic of SEM Meta-...
514 views

### Fitting a psychometric function when data does not lend itself to a sigmoidal fit

I'm fitting a psychometric function to a range of data. The majority of this data lends itself to a sigmoidal fit (i.e. participants can do the task), but some individuals are absolutely unable to do ...
187 views

### Are there any journal articles in psychology that have promoted and discussed reproducible data analysis?

I consider reproducible analysis to be really important. In particular, I'd like to see more researchers in psychology: sharing their data producing their journal articles using literate programming ...
5k views

### What is the standard way to analyze EEG data in a mismatch negativity paradigm?

I'm running an EEG experiment using a modified auditory mismatch negativity (MMN) design, and I'm wondering if anyone can tell me the best method for data analysis (and recommend any stats programs/...
471 views

### The current recommended text for statistics in behavioural sciences

I have an old book: Statistics for the Behavioural Sciences (4th ed.) by Gravetter & Wallnau. I want to transition my textbooks to eBook format, but this book doesn't come like that (as far as I ...
168 views

### Which statistical test should I use when there are multiple latent predictors and multiple latent outcomes?

Which statistical method should I use when Predicting organization commitment (composed of 3 latent variables) using the five factors of personality? Its a cross-sectional design with survey data. ...
561 views

### Introductory resources on bayesian modeling for cognitive sciences

On Cross Validated there is a great question about best introductory books for bayesian statistics. Also, Jeromy Anglim blogged recently about use of JAGS, rjags, and Bayesian Modelling, with some ...
10k views

### How to analyze reaction times and accuracy together?

Is there a good way to analyze reaction times and accuracy together, other than MANOVA? I have data from an experiment in which participants had to respond to stimuli in two different conditions in a ...