Linked Questions

343
votes
78answers
161k views

What is your favorite “data analysis” cartoon?

This is one of my favorites: One entry per answer. (This is in the vein of the Stack Overflow question What’s your favorite “programmer” cartoon?.) P.S. Do not hotlink the cartoon without the site's ...
298
votes
16answers
101k views

Is normality testing 'essentially useless'?

A former colleague once argued to me as follows: We usually apply normality tests to the results of processes that, under the null, generate random variables that are only asymptotically or ...
76
votes
5answers
18k views

What are modern, easily used alternatives to stepwise regression?

I have a dataset with around 30 independent variables and would like to construct a generalized linear model (GLM) to explore the relationship between them and the dependent variable. I am aware that ...
39
votes
7answers
3k views

What are the most common biases humans make when collecting or interpreting data?

I am an econ/stat major. I am aware that economists have tried to modify their assumptions about human behavior and rationality by identifying situations in which people don't behave rationally. For ...
46
votes
8answers
4k views

Pitfalls in time series analysis

I am just starting out self-learning in time series analysis. I have noticed that there are a number of potential pitfalls that are not applicable to general statistics. So, building on What are ...
44
votes
5answers
2k views

Statistics published in academic papers

I read a lot of evolutionary/ecological academic papers, sometimes with the specific aim of seeing how statistics are being used 'in the real world' outside of the textbook. I normally take the ...
19
votes
2answers
10k views

How to choose random- and fixed-effects structure in linear mixed models?

Consider the following data from a two-way within subjects design: ...
21
votes
4answers
961 views

To what extent is the distinction between correlation and causation relevant to Google?

Context A popular question on this site is " What are common statistical sins?". One of the sins mentioned is assuming that "correlation implies causation..." link Then, in the comments with 5 ...
4
votes
3answers
8k views

Variable is significant through stepwise regression but not in final model's summary; which should I report?

I used generalized linear mixed models (with the glmmADMB package) to identify environmental factors related to parasite abundance in rodents. I used stepwise ...
7
votes
2answers
7k views

Checking factor / covariate independence in ANCOVA

One of the ANCOVA assumptions, as I read it here, says that: Independent variables orthogonal to covariates. In traditional ANCOVA, the independents area assumed to be orthogonal to the factors. If ...
4
votes
4answers
949 views

Why is it a “statistical sin” to run a large number of correlations and only report the statistically significant ones?

I recently read the following statistical 'sin' here: Something I see a surprising amount in conference papers and even journals is making multiple comparisons (e.g. of bivariate correlations) and ...
12
votes
3answers
439 views

Is it better to select distributions based on theory, fit or something else?

This is bordering on a philosophical question, but I am interested in how others with more experience think about distribution selection. In some cases it seems clear that theory might work best (mice ...
0
votes
2answers
23k views

How to analyze my Likert-scale data

I am collecting data from a group of about 189 police officers on a 5-point Likert-Scale (measuring how much the police officers accept rape myths). I have no idea which tests to use to analyse my ...
4
votes
2answers
5k views

Evaluating effect sizes of interactions in multiple regression

I have been running 3-level multilevel models with HLM, and my main interest is in some cross-level interaction effects that I am finding. My concern is that the effect sizes of these interactions ...
2
votes
1answer
4k views

Mixed models and backward elimination

Let's say I have a data like this, and I'm trying to build a mixed model. ...

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