Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [f-test]

Any hypothesis test in which the statistic has an F distribution under the null hypothesis.

An F-test is any statistical test in which the test statistic has an F-distribution under the null hypothesis. It is most often used when comparing statistical models that have been fitted to a data set, in order to identify the model that best fits the population from which the data were sampled.

Wikipedia

359 questions
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Why are different answers obtained for a regression F-test when using SSE and R2 formulas?

I cannot understand what I'm doing wrong with an F-test for the regression - I get completely different answers using SSE and R2 formulas. Unrestricted model: Restricted model: 1 restriction is imposed, so q=1 in both cases. Calculation with…
user14386
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F test fails but t-test does not?

I'm a bit confused about this. I have a model with multiple variables trying to explain the dependent variable. When I use the F test, I don't pass the critical value. But when I seperate the different variables and use the t-test, I do pass the…
Orbit
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How should I treat F test if one of variances is equal 0?

I have two groups with 20 elements in each. In one group variance is equal 0. I want to do f-test. Can I? And how should I interpret results (in this case)?
Frozen
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F-test for CO2 and Temperature, Find F values for both?

Given: Yield Temp CO2 0 57 3.6 305 1 73 3.5 325 2 96 3.7 345 3 100 3.8 353 4 99 4.0 360 5 104 4.1 369 For regression on Yield on CO2 and Temperature, I got F- test values as F-value for CO2:…
Kaleab Woldemariam
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How to estimate critical value for F-test for df=91?

I'm trying to do F-test (ratio of the variances) for two samples with 92 data points each. I look at several links for the critical value for degrees of freedom equal to 91 but most of them are skipping values in between. For example, from the link…
Lyndz
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F-test for equality of variance

Assuming perfect normality, independence, etc. and testing for equality of variance between two population (where we know that $\sigma_x^2 $ is not lower) and (thus) use a one-sided test. $$H_0: \sigma_x^2 = \sigma_y^2 $$ $$H_1: \sigma_x^2 -…
snoram
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One tailed or two tailed test?

I have a simple question. I'm not sure which one to use, whether it should be one tailed or two tailed test. I have two sets of data - any type of measurements. First test is in perfect conditions and the second one is where the measurements are…
Natalia
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In the F test, is a two-sided test mainly used?

I have a question about the F test. In R language, three parameters "two.side", "less" and "greater" can be specified as arguments of var.test (). However, I can not specify a one-sided test like "one.side". Also, in Microsoft Excel, the F. TEST…
nekoneko
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Can I mix and match F-test and T-test code when I implement a program for some statistical calculations?

I was told to rewrite an old java program that performs some statistical calculations. I was able to solve most of the problems until I ran into this one: The program compares two sets of data over 100 samples. I have standard deviations for both…
ruby_object
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Does the F-Test (var.test in R) assume independence of observations?

I've looked online but I can't seem to find an answer. Basically I'm comparing data from two groups, disease and control, and from each induvidual there's two observations. I want to compare the groups to see if one has a larger variance than the…
TheFoxx
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Finding value of f statistic to test for difference between treatment means given the following table

Im not really good with statistics and cant really find a way to answer this question. Finding value of f statistic to test for difference between treatment means given the following table.
arjun
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Interpreting the results of an analysis

Possible Duplicate: How to interpret basic output from a regression analysis? I am wondering what does the following stand for: F( 2, 27) = 19.73. As far as I understand his has to do with the F-test. I don't know how to interpret this. Could…
Mimi
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