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English: Skill Group B

Part 1 Test whether the degree of malignancy significantly predicts recurrence. Use a significance level of 0.01. This is statistically significant as the p-value is less than 0.0001. Thus, it predicts recurrence. Part 2 Test whether tumor size predicts recurrence. Use a significance level of 0.01. The p-value is 0.0409. this is more than 0.01 meaning that it is not statistically significant. Thus, it does not predict recurrence. Part 3 In a univariate model with just the tumor size covariate, the chi-squared value for the whole-model test is 8.88. For this univariate model, test whether tumor size predicts recurrence. Use a significance level of 0.01.

The critical value of that is 3.84.  The chi-squared value of 8.88 is more than the critical value. Thus, the tumor size does not predict recurrence.

Part 4 Do your results from parts 2 and 3 agree with each other? If not, what explains the difference?

They don’t agree with each other. The difference comes from as one is a univariate model and the other one is multi-variate. Meaning that the effect on the multi variate is smaller.