critical value
(noun)
the value corresponding to a given significance level
Examples of critical value in the following topics:
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95% Critical Values of the Sample Correlation Coefficient Table
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Testing the Significance of the Correlation Coefficient
- METHOD 2: Using a table of Critical Values to make a decision
- Compare r to the appropriate critical value in the table.
- If r < negative critical value or r > positive critical value, then r is significant.
- The critical values are -0.532 and 0.532.
- The critical values are -0.811 and 0.811.
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Estimating a Population Variance
- The value of ${ X }_{ R }^{ 2 }$represents the right-tail critical value.
- The value of ${ X }_{ L }^{ 2 }$represents the left-tail critical value.
- Using the values $n=30$, $\text{d.f.} = 29$ and $c=0.99$, the critical values are 52.336 and 13.121, respectively.
- Note that these critical values are found on the chi-square critical value table, similar to the table used to find $z$-scores.
- Using these critical values and $s=1.2$, the confidence interval for $s^2$ is as follows:
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Try these multiple choice questions
- No, because 0.942 is greater than the critical value of 0.707
- Yes, because 0.942 is greater than the critical value of 0.707
- No, because 0942 is greater than the critical value of 0.811
- Yes, because 0.942 is greater than the critical value of 0.811
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Hypothesis Tests with the Pearson Correlation
- The 95% critical values of the sample correlation coefficient table shown in gives us a good idea of whether the computed value of $r$ is significant or not.
- Compare $r$ to the appropriate critical value in the table.
- If $r$ is not between the positive and negative critical values, then the correlation coefficient is significant.
- The critical values associated with $df=8$ are $\pm 0.632$.
- If $r$ is less than the negative critical value or $r$ is greater than the positive critical value, then $r$ is significant.
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Rank Randomization for Association (Spearman's ρ)
- Table 1 shows 5 values of X and Y.
- Since it is hard to count up all the possibilities when the sample size is even moderately large, it is convenient to have a table of critical values.
- From the table shown below, you can see that the critical value for a one-tailed test with 5 observations at the 0.05 level is 0.90.
- As shown above, the probability value is 0.042.
- Since the critical value for a two-tailed test is 1.0, Spearman's ρ is not significant in a two-tailed test.
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Estimating the Target Parameter: Interval Estimation
- Interval estimation is the use of sample data to calculate an interval of possible (or probable) values of an unknown population parameter.
- Interval estimation is the use of sample data to calculate an interval of possible (or probable) values of an unknown population parameter.
- A confidence interval for is calculated by: $\bar{x}\pm t^{*}\frac{s}{\sqrt{n}}$, where $t^*$ is the critical value for the $t(n-1)$ distribution.
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Rank Randomization: Two Conditions (Mann-Whitney U, Wilcoxon Rank Sum)
- First, consider how many ways the 8 values could be divided into two sets of 4.
- Table 6 can be used to obtain the critical values for equal sample sizes of 4-10.
- Since the sum of ranks equals 24, the probability value is somewhat above 0.05.
- Naturally a table can only give the critical value rather than the p value itself.
- Therefore, for practical reasons, the critical value sometimes suffices.
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Goodness of Fit
- A measure of goodness of fit typically summarize the discrepancy between observed values and the values expected under the model in question.
- The observed values are the data values and the expected values are the values we would expect to get if the null hypothesis was true.
- The null hypothesis for the above experiment is that the observed values are close to the predicted values.
- This is done in order to check if the null hypothesis is valid or not, by looking at the critical chi-square value from the table that corresponds to the calculated $\nu$.
- The critical value for a chi-square for this example at $a = 0.05$ and $\nu=1$ is $3.84$, which is greater than $\chi ^ 2 = 0.36$.
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Critical Thinking
- The essential skill of critical thinking will go a long way in helping one to develop statistical literacy.
- Statistical literacy is necessary to understand what makes a poll trustworthy and to properly weigh the value of poll results and conclusions.
- The essential skill of critical thinking will go a long way in helping one to develop statistical literacy.
- Critical thinking is an inherent part of data analysis and statistical literacy.
- Interpret the role that the process of critical thinking plays in statistical literacy.