4k views

How to interpolate for the normal distribution (or any other distribution)? [duplicate]

I have that X is normally distributed with mean 4 and variance 9 and I need to calculate the probability: Pr(X>9). So far, I have Pr(X>9)=Pr(Z>5/3)=1-Pr(Z<5/3). Now, the value for Pr(Z<5/3) ...
674 views

How to interpolate for degrees of freedom from a $\chi^{2}$ table [duplicate]

The question asks to find $\chi^{2*}$ that cuts off 5% of the tail with df=52. the chart given lists df=50 then jumps to 60
48 views

How to choose critical F value from statistical tables when the df is large? [duplicate]

For an F(2, 237) distribution, how should I determine a critical F value from a statistical table? Would I look up (2, 150) or (2, 300)? Should it simply be the closest degrees of freedom?
41 views

How to estimate critical value for F-test for df=91? [duplicate]

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 ...
6k views

What do you do if your degrees of freedom goes past the end of your tables?

The degrees of freedom in my F table don't go up high enough for my big sample. For example, if I have an F with 5 and 6744 degrees of freedom, how do I find the 5% critical value for an ANOVA? What ...
71k views

How to get F-test p-value

Suppose we can choose from two different catalysers. 10 observations are taken from the first one and 12 from the other one. If $s_1 = 14$ and $s_2 = 28$, can we reject at $\alpha = 5\%$ the ...
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How exactly does null hypothesis testing work

I'm trying to gain a better understanding of how null hypothesis testing works. I have 3 questions related to the code below: Am I right in saying the probability of each t value in ...
18k views

How to read off 0.975 alpha value in F table

$F<(1-\alpha/2, n_x-1, n_y-1)$ and $F>(\alpha/2, n_x-1, n_y-1)$. (Testing equality of population variances). An alpha of $0.0$5 is used. $1-\alpha/2= 1-0.05/2= 1-0.025= 0.975$. However, there ...
1k views

How to calculate critical values ($W_{\alpha}$) for the Shapiro-Wilk test?

When performing the Shapiro-Wilk test, we can obtain the critical $W_{\alpha}$ statistic from tables, given $\alpha$ is 0.05 or 0.01. If $\alpha$ is nonstandard, say 0.07 or 0.02 for example, how we ...
2k views

Anova one way (getting different p-values in calculator and F table). Why?

I am resolving an anova one-way exercise. But I am doubtful because when using the F-table to get the p-value, I am getting a probability around 2.2 (an obvious error), but if I use a calculator the ...
4k views

Calculating the “critical value” for F test

I'm following along here: http://reliawiki.org/index.php/Multiple_Linear_Regression_Analysis#Calculation_of_the_Statistic I've successfully made all of the calculations up to $f_0=211.9$. Now I need ...
3k views

How to get P-Value when t value is less than 1?

I am doing an assignment for class and I have hit a wall. I'm not sure what to do next. Using a sample with 12 discrete elements, I am trying to test a hypothesis that the population mean is 243 ...
2k views

Why use the F distribution and F test?

I don't understand why in the F test we calculate the ratio between MSE between subject and MSE within subject. As far as I know, this is due because we want to use the F distribution, which is a rate ...
How to find exact p-value of Pearson $\chi^2$ test?
In a book I am reading, the authors have calculated the Pearson $\chi^2$ statistic value as 11.50 with degrees of freedom = 9. The p-value stated is 0.241. I looked it up in a $\chi^2$ table but I ...