Refers generally to making substantive conclusions from the results of a statistical analysis.
Questions tagged [interpretation]
2104 questions
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How to understand degrees of freedom?
From Wikipedia, there are three interpretations of the degrees of freedom of a statistic:
In statistics, the number of degrees of freedom is the number of
values in the final calculation of a statistic that are free to vary.
Estimates of…
Tim
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What is the meaning of p values and t values in statistical tests?
After taking a statistics course and then trying to help fellow students, I noticed one subject that inspires much head-desk banging is interpreting the results of statistical hypothesis tests. It seems that students easily learn how to perform the…
Sharpie
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Interpretation of R's lm() output
The help pages in R assume I know what those numbers mean, but I don't.
I'm trying to really intuitively understand every number here. I will just post the output and comment on what I found out. There might (will) be mistakes, as I'll just write…
Alexander Engelhardt
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Removal of statistically significant intercept term increases $R^2$ in linear model
In a simple linear model with a single explanatory variable,
$\alpha_i = \beta_0 + \beta_1 \delta_i + \epsilon_i$
I find that removing the intercept term improves the fit greatly (value of $R^2$ goes from 0.3 to 0.9). However, the intercept term…
Ernest A
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Clustering on the output of t-SNE
I've got an application where it'd be handy to cluster a noisy dataset before looking for subgroup effects within the clusters. I first looked at PCA, but it takes ~30 components to get to 90% of the variability, so clustering on just a couple of…
generic_user
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How to interpret an inverse covariance or precision matrix?
I was wondering whether anyone could point me to some references that discuss the interpretation of the elements of the inverse covariance matrix, also known as the concentration matrix or the precision matrix.
I have access to Cox and Wermuth's…
Vinh Nguyen
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How to interpret coefficients in a Poisson regression?
How can I interpret the main effects (coefficients for dummy-coded factor) in a Poisson regression?
Assume the following example:
treatment <- factor(rep(c(1, 2), c(43, 41)),
levels = c(1, 2),
…
user734124
65
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6 answers
Real-life examples of moving average processes
Can you give some real-life examples of time series for which a moving average process of order $q$, i.e.
$$
y_t = \sum_{i=1}^q \theta_i \varepsilon_{t-i} + \varepsilon_t, \text{ where } \varepsilon_t \sim \mathcal{N}(0, \sigma^2)
$$
has some a…
weez13
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Is this chart showing the likelihood of a terrorist attack statistically useful?
I'm seeing this image passed around a lot.
I have a gut-feeling that the information provided this way is somehow incomplete or even erroneous, but I'm not well versed enough in statistics to respond. It makes me think of this xkcd comic, that even…
LCIII
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Is it wrong to rephrase "1 in 80 deaths is caused by a car accident" as "1 in 80 people die as a result of a car accident?"
Statement One (S1): "One in 80 deaths is caused by a car accident."
Statement Two (S2): "One in 80 people dies as a result of a car accident."
Now, I personally don't see very much difference at all between these two statements. When writing, I…
faulty_ram_sticks
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Interpretation of log transformed predictor and/or response
I'm wondering if it makes a difference in interpretation whether only the dependent, both the dependent and independent, or only the independent variables are log transformed.
Consider the case of
log(DV) = Intercept + B1*IV + Error
I can…
upabove
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Interpreting QQplot - Is there any rule of thumb to decide for non-normality?
I have read enough threads on QQplots here to understand that a QQplot can be more informative than other normality tests. However, I am inexperienced with interpreting QQplots. I googled a lot; I found a lot of graphs of non-normal QQplots, but no…
greymatter0
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How to interpret coefficients from a polynomial model fit?
I'm trying to create a second order polynomial fit to some data I have. Let's say I plot this fit with ggplot():
ggplot(data, aes(foo, bar)) + geom_point() +
geom_smooth(method="lm", formula=y~poly(x, 2))
I get:
So, a second order fit…
user13907
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Interpretation of R's output for binomial regression
I'm quite new on this with binomial data tests, but needed to do one and now I´m not sure how to interpret the outcome. The y-variable, the response variable, is binomial and the explanatory factors are continuous. This is what I got when…
user40116
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How to interpret F- and p-value in ANOVA?
I am new to statistics and I currently deal with ANOVA. I carry out an ANOVA test in R using
aov(dependendVar ~ IndependendVar)
I get – among others – an F-value and a p-value.
My null hypothesis ($H_0$) is that all group means are equal.
There…
JanD
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