Linked Questions

5 votes
3 answers
16k views

Chi-Square-Test: Why is the chi-squared test a one-tailed test? [duplicate]

In my Masters thesis I conducted an experiment in that subjects should decide between two alternatives. I had a control and a treatment group. The hypothesis was that in the treatment group more ...
StepMuc's user avatar
  • 73
0 votes
0 answers
48 views

what type of hypotheses does "goodness of fit" signifies , i.e is it single tailed or two tailed? [duplicate]

Suppose it is required to test the fitting of binomial distribution to the following data ( at level $\alpha =0.05$) : the parameter p is estimated as p = 0.494 , and the expected frequencies (given ...
ANUJ NAIN's user avatar
  • 663
1 vote
0 answers
16 views

Why is there only one critical value in the Wald confidence interval [duplicate]

Im currently studying the Wald test statistic for testing $ H_0: \boldsymbol{R'\hat{\beta}} = \boldsymbol{r} $ given by $$ W = \frac{(\boldsymbol{R'\hat{\beta}} - \boldsymbol{r})'(\boldsymbol{R'(X'X)R)...
Pim's user avatar
  • 81
48 votes
5 answers
6k views

Fake uniform random numbers: More evenly distributed than true uniform data

I'm looking for a way to generate random numbers that appear to be uniform distributed -- and every test will show them to be uniform -- except that they are more evenly distributed than true uniform ...
Has QUIT--Anony-Mousse's user avatar
20 votes
4 answers
99k views

R: calculate p-value given Chi Squared and Degrees of Freedom

How can I calculate the p-value given Chi Squared and the Degrees of Freedom? For example, what would be the exact p-value of a Chi Squared = 15 with df = 2?
mat's user avatar
  • 613
8 votes
3 answers
33k views

Interpretation of Little's MCAR test

My Little's MCAR (missing completely at random) test on 74 items and 151 cases revealed chi-square = 27.120, DF = 1974, and sig. = 1.000. Can I conclude that ...
user44391's user avatar
17 votes
1 answer
6k views

Which test for cross table analysis: Boschloo or Barnard?

I am analyzing a 2x2 table from a small dataset of 30 patients. We are retrospectively trying to find some variables that give a hint about which treatment to choose. The variables (obs normal / ...
Taz's user avatar
  • 338
8 votes
4 answers
2k views

$\chi^2$ tabulated value

I noticed that the critical $\chi^2$ value increases as the degrees of freedom increase in a $\chi^2$ table. Why is that?
Cynderella's user avatar
6 votes
3 answers
7k views

What is the meaning of a large p-value?

I understand that the $p$-value is the conditional probability of observing the test statistic or something more extreme given that the null hypothesis is true. I have read the great explanation by @...
renrenthehamster's user avatar
6 votes
1 answer
5k views

Chi-squared distribution for dice not returning expected values?

I'm trying to verify that my dice are reasonably fair and balanced. I'm not sure I'm doing it right, though, since I'm basically teaching myself stats without references. To achieve this, I've settled ...
user avatar
13 votes
2 answers
1k views

How to define a Rejection Region when there's no UMP?

Consider the linear regression model $\mathbf{y}=\mathbf{X\beta}+\mathbf{u}$, $\mathbf{u}\sim N(\mathbf{0},\sigma^2\mathbf{I})$, $E(\mathbf{u}\mid\mathbf{X})=\mathbf{0}$. Let $H_0: \sigma_0^2=\...
An old man in the sea.'s user avatar
6 votes
1 answer
4k views

One-sided McNemar's test

In R, the function mcnemar.test has the following example: ...
thc's user avatar
  • 448
4 votes
1 answer
10k views

Chi-square test p-value = 1

I am attempting to use the chi-square test as a goodness-of-fitness test in R, but I keep getting a p-value = 1. I expect a high p-value, but less than one. Can anyone point out what error I might be ...
bender's user avatar
  • 43
2 votes
2 answers
5k views

What is null hypothesis in the deviance goodness of fit test for a GLM model?

To test the goodness of fit of a GLM model, we use the Deviance goodness of fit test (to compare the model with the saturated model). In many resource, they state that the null hypothesis is that &...
InTheSearchForKnowledge's user avatar
3 votes
1 answer
2k views

Chi-Square test: one-sided implementation?

I need to compare two samples and I would like to know if the distribution of the first stochastically dominates that of the second one. I'm not sure whether with the Chi-Square test I can verify ...
Ricky Robinson's user avatar

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