Linked Questions

2
votes
2answers
257 views

Ambiguity of chi-squared test of association; how can the conclusion change using the ''same'' sample?

Recently I have been struggling with the following two questions regarding the chi-squared test of independence / association during reading an article. Is the chi-squared test able to detect no ...
1
vote
2answers
7k views

How to interpret MCAR (missing completely at random) any papers that I can read?

When dealing with missing data and Little's missing completely at random test, it's widely considered that if the test has a significance level of P>0.05 the data can be considered as MCAR. But, I ...
0
votes
2answers
143 views

What fraction to use in the formulation of a hypothesis test ? - Population fraction versus sample fraction

Imagine that I am studying racial discrimination. In particular, whether a white candidate (for a job) is chosen more often than an equally qualified minority candidate. I ask people to choose ...
0
votes
2answers
187 views

ANOVA for Regression

When using ANOVA to compare means, I understand the null hypothesis is u1=u2=u3.... as we need to combine all groups into a single group when assuming their means are the same. But for ANOVA for ...
-1
votes
2answers
85 views

Definition of alternative hypothesis

Which of these properties is required of the alternative hypothesis, by definition, in the general case: a) If the alternative hypothesis is true, then the null hypothesis would necessarily tend ...
12
votes
1answer
5k views

Goodness-of-fit test in Logistic regression; which 'fit' do we want to test?

I am referring to the question and its answers: How to compare (probability) predictive ability of models developed from logistic regression? by @Clark Chong and answers/comments by @Frank Harrell. ...
11
votes
1answer
956 views

What are the ''desirable'' statistical properties of the likelihood ratio test?

I am reading an article whose method is fully based on the likelihood ratio test. The author says that the LR test against one sided alternatives is UMP. He proceeds by claiming that "...even when ...
3
votes
1answer
136 views

Probability of significant result in a second sample given first was significant

It's an example mentioned in Amos Tversky and Daniel Kahneman's Belief in the Law of Small Numbers: Suppose you have run an experiment on 20 subjects, and have obtained a significant result which ...
2
votes
1answer
5k views

Test if two normally distributed random variables have the same mean

We have two independent random variables which follow normal distributions $X_1\sim \mathcal N(\mu_1,\sigma_1)$, $X_2\sim \mathcal N(\mu_2,\sigma_2)$. From the context, we have that $\mu_1\leq\mu_2$. ...
0
votes
1answer
53 views

Power of a test in testing of hypothesis

Power in testing of hypothesis is defined as the probability of making the correct decision. Then why do text books describe power=1-P(type 2 error) and not 1-P(type 1 error)
0
votes
1answer
26 views

hypotheses testing [duplicate]

so I'm new to statistics and am not very comfortable with it yet. It may be a very simple question, but I'm finding this very difficult to understand In research papers the hypotheses are mostly in a ...
3
votes
0answers
89 views

How can we reject null hypothesis based on p-values? [closed]

In textbook statistical tests, we usually calculate the probability of observing the data we observed given that the null hypothesis is true, i.e. $P[D|H_0]$. If this probability is small (e.g. $<0....
1
vote
0answers
50 views

What basis should be used to devize a significance/hypothesis test?

I am trying to understand the basis of hypothesis testing and I came up with a paradox. Let me explain with an example. Consider the case of trying to determine whether is coin is fair. The null ...
0
votes
0answers
211 views

what “rejecting a null hypothesis” actually means?

I have a sample dateset consists two variables as "Score"(independent continuous) consists score of students in maths and school(dependent categorical)having 3 categories as "S1","S2","S3". I'd ...
0
votes
0answers
36 views

Interpreting hypothesis testing result (assuming that the null hypothesis is true) [duplicate]

I have a doubt on how to interpret a result of a hypothesis test. For example, a scenario where I have an existing configuration and also a new configuration. I am trying to check if with the new ...

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