How much variance in my p-value

In summary, the p-value represents the probability of obtaining results at least as extreme as the observed results, assuming the null hypothesis is true. A p-value of less than 0.05 is considered statistically significant and indicates that the null hypothesis should be rejected. A p-value greater than 0.05 suggests that the observed results are likely to occur by chance and that the null hypothesis cannot be rejected. A high p-value does not necessarily mean that there is no effect, but rather that there is not enough evidence to reject the null hypothesis. Sample size can affect the p-value, with a larger sample size generally resulting in a smaller p-value. However, the exact relationship between sample size and p-value can vary. A low p-value does
  • #1
Nyasha
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So l have a nuclear counting system which follows a poisson distribution. I have taken 5 data sets consisting of 30 counts each and l have used them in a chi squared gof test to see if they follow a poisson distribution. For each data set my p-value has been changing. Initially it was 0.5 then 0.7, 08, 02, 0.3 Is this normal or is it a cause of worry ?
 
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  • #2
The p-value you get off the chi-square test will be different between datasets, that is normal. It is not normal for the reference p-value to change.
Consider: what does the p-value actually represent?
 

Related to How much variance in my p-value

1. How do I interpret the p-value in my research?

The p-value represents the probability of obtaining results at least as extreme as the observed results, assuming that the null hypothesis is true. A p-value of less than 0.05 is typically considered statistically significant and indicates that the null hypothesis should be rejected.

2. What does it mean if my p-value is greater than 0.05?

A p-value greater than 0.05 indicates that the observed results are likely to occur by chance and that the null hypothesis cannot be rejected. This suggests that there may not be a significant relationship between the variables being studied.

3. Can a high p-value be interpreted as proof that there is no effect?

No, a high p-value does not necessarily mean that there is no effect. It simply means that there is not enough evidence to reject the null hypothesis. Other factors, such as sample size and study design, should also be considered when interpreting the results.

4. How does sample size affect the p-value?

A larger sample size generally results in a smaller p-value, as it provides more precise estimates of the true effect. This is because a larger sample size reduces the variability in the data and increases the power of the study. However, the exact relationship between sample size and p-value can vary depending on the study design and other factors.

5. Is a low p-value always a reliable indicator of a significant result?

Not necessarily. A low p-value can indicate a significant result, but it does not guarantee that the observed effect is meaningful or that it will generalize to a larger population. Other factors, such as effect size and study design, should also be considered when evaluating the significance of a result.

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