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Statistical test for binomial draws with unknown number of trials

Turning my earlier comment into an asnwer, as requested by @jbowman Assuming first that you are trying to test whether your observed counts X1 and X2 are compatible with the estimated proportions p1 ...
jginestet's user avatar
  • 268
2 votes
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When testing significance between a regression coefficient of two data sets using a Z-test, how to interpret the z-value?

If your null hypothesis is that the two slopes are equal, then you expect z to be zero on average, with random sampling giving it a value away from zero. If the null is false, you expect z to be far ...
Harvey Motulsky's user avatar
0 votes

How to compare frequencies of categorical variable with 3 possible values

Without knowing more context, I would try bootstrapping. In this case this would amount to sampling repeatedly with replacement from your observations, for each resample note if the maximum is for A. ...
kjetil b halvorsen's user avatar
6 votes
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Statistical tests for data on occurrence of reptiles found under different types of artifical cover objects

As a biologist I really like you experiment! So I thought I give you an idea of how this type of data can be analyzed. I am working in R so my post will be R-centric, but the general process is the ...
Stefan's user avatar
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10 votes

How does reducing my alpha-threshold to 0.005 affect my required sample size?

As you wrote ".. there is no "simple" function mapping the old size to the new one .." --this is what I expected. However, following your suggestion and then plotting new against ...
PuzzledBiologist's user avatar
10 votes
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How does reducing my alpha-threshold to 0.005 affect my required sample size?

There is very likely no "simple" function mapping the old sample size to the new one. The way to go about this would be to calculate the effect size detectable at the "old" sample ...
Stephan Kolassa's user avatar
-1 votes

How to check if a value in a time series is significantly different from other values?

You can use Z-score in the context of anomaly detection. Z-score is probably the simplest algorithm that can rapidly screen candidates for further examination to determine whether they are suspicious ...
user407203's user avatar
3 votes

Which statistic to use for measurement between two samples

The KS test is a test of the null hypothesis that normal stem widths and mutant stem widths were drawn from the same continuous distribution. I would probably think that you perhaps are interested in ...
Stefan's user avatar
  • 5,971
3 votes

Which statistic to use for measurement between two samples

It depends on the parameter of interest. The KS test compares the whole cumulative distribution functions. A significant result could be because of different means, medians, variances, skewness, ...
DrJerryTAO's user avatar
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3 votes
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Appropriate method for seeing how similar two items on a survey are?

If you want to look at difference then you can look at plots of the average difference, the average absolute difference, a Tukey mean difference plot (aka Bland Altman plot) and so on. You can also ...
Peter Flom's user avatar
  • 117k
3 votes

Hypothesis testing for detecting a (damped) sinusoidal signal in noise

In engineering context likelihood ratio test is a typical approach for signal detection. The Poissonian noise for $N\gg 1$ can be viewed as Gaussian, which allows to write the joint probability ...
Roger V.'s user avatar
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4 votes

Hypothesis testing for detecting a (damped) sinusoidal signal in noise

It may be possible to use Bayesian statistics here. Let's set testing aside for a moment and instead focus on estimation. If we can construct a model and assess the estimates of $A$, maybe we can say ...
Demetri Pananos's user avatar
5 votes

Hypothesis testing for detecting a (damped) sinusoidal signal in noise

My intuition tells me: build an optimal filter using e.g. a correlation with your expected signal r(t_i): see first example under https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal....
Ggjj11's user avatar
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5 votes

Remove non-significant independent variabels and re-run multiple regression

No. You should report the results you've got. Three of your variables are important for your theory. The other two have been shown to be large in other studies. So, you should keep them all. Don't ...
Peter Flom's user avatar
  • 117k
11 votes

Statistically significant difference

The authors are telling you that the VAS score for IPC group is "significantly different" from the VAS score from the talc group. In other words, they are saying that the SIZE of the ...
Graham Wright's user avatar
5 votes

Statistically significant difference

User2974951's is correct and to the point. For further readers that are still wondering where that 0 comes from and why it doesn't make sense to look at the '-14', which is a common mistake for ...
Mathemagician777's user avatar
8 votes

Statistically significant difference

Implicit in the comment is that the test is of a null hypothesis that the value is zero. It is possible to test other null hypotheses, but “is it zero or not” is a common question to have and common ...
Dave's user avatar
  • 61k
6 votes

Statistically significant difference

You got that wrong, -14 is the "middle" (not necessarily) of the CI, the result would be suspect if the CI contained 0 in it, so for ex. a CI from -25 to +2.
user2974951's user avatar
  • 7,753
1 vote

Is there a robust test for stochastic dominance between two random variables?

You could rank your observations and report the proportion of ranked values in each of the group and say something like, Proportion of higher ranked values in A > Proportion of higher ranked values ...
Rohan Sarkar's user avatar
4 votes
Accepted

Statistical testing on non-random sample?

The result of your analysis (regression, or whatever you did) are valid for your sample; the effect sizes are accurate estimates for your sample. But the validity of any generalization relies on your ...
Peter Flom's user avatar
  • 117k
0 votes

Binomial test to establish a pass criterion

You've gotten a couple of answers that are statistical in nature, showing how to model things with a binomial distribution and eliminate a lot of people who randomly guess. If that's what you want, ...
Peter Flom's user avatar
  • 117k
0 votes
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Binomial test to establish a pass criterion

You can use the binomial density function (dbinom in R) to determine the probability of a specific outcome given a total number of trials $n=12$ and their ...
PBulls's user avatar
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0 votes

Binomial test to establish a pass criterion

For someone who randomly guesses, the number of successes in 12 trials is $X \sim \text{Binomial}(12, 1/3)$. One possible setup: You can use R functions to find a number $q$ such that $P(X > q) <...
angryavian's user avatar
  • 2,238
1 vote

Statistical significance for high values of IV

While it is absolutely possible for the relationship to change over the range of the IV. Though the simple way to test for this is to plot the DV and the IV using a scatterplot. If the plot's general ...
Sam Levi's user avatar
0 votes
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Statistical significance different observation windows

When comparing two means, the usual thing is an independent sample t-test. This makes certain assumptions which can be checked: Data are continuous Random sample from a population At least ...
Peter Flom's user avatar
  • 117k
2 votes

Statistical significance for high values of IV

It's probably best to ask your professor what he wants. I can think of two things I might do (assuming no guidance is available). First, I would simply make scatter plots and look. If something more ...
Peter Flom's user avatar
  • 117k
8 votes

Regression model not significant, but the predictor significant

Your question is very similar to this question, except that you had a prior hypothesis about the association between $x$ and $y$. As this answer to that question points out, having too many predictors ...
EdM's user avatar
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1 vote

1 question. 6 factors. Each with a Likert scale from 1 to 5. How can I analyze the results to answer my hypothesis?

Your hypothesis can be tested by comparing the responses to the taste Likert item against those to each of the other 5 Likert items. It doesn't require a ...
EdM's user avatar
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