B3 REPLIES

Nitha

From the graph it appears that patients who are depressed have a 14% chance of developing cancer. While, persons who are not depressed have a 5% change of getting cancer. Whereas persons who are not depresses have a 94% chance of not developing cancer. And 84% chance of getting cancer. Findings 1. chances are that persons with cancer have a higher possibility of being depressed. 2. It also shows that being depressed does not mean that your chances of getting canner is significantly higher since persons who are not depresses have a 94% chance of not developing cancer. And 84% chance of getting cancer.

CATHERINE

Based on the tables and graphs that I created, it appears that there is a strong link between having cancer and being depressed. The probability of depression given that someone has cancer is 77.3% compared to the probability of just having depression (56.5%). It makes sense that cancer is associated with higher levels of depression. It is a dark time in a person's life. On the other hand, having depression does not have such an extreme effect on having cancer. The probability of having cancer given that someone is depressed is 14.5%. The probability of having cancer in general is 10%. It is slightly higher.

D4

CATHERINE

Based on the very low p-value (<0.0001), we should reject the null hypothesis that there is not an association between the two variables. There is strong evidence to show that there is an association between cancer and depression. We cannot conclude that one causes the other due to the fact that it is an observational study and not an experiment. It would be unethical to do an experiment for this situation. Based on the data it appears that having cancer increases the likelihood that you have depression. There could be a lurking variable at play here. For example, obesity has been linked to cancer and it has also been linked to depression. That could be the lurking variable.

NITHA

The Chi Square Test allows you to determine the there is an association between the variables, the chi- square was really large: 43.13. The probability of getting a chi square statistic

as high as 43.13, if the variables are truly unrelated (independent) was very low as the p value was 5.12 x 10^-11. As a result the p value is  much smaller than the  less than the

0.5% significance level. We therefore reject the null hypothesis which states that there is no association between depression and cancer or Having Depression and Having Cancer are

independent.

We however cannot conclude that one causes another. What we can say is that there is an association. There may be other lurking variables that may affect the findings which include

diet or nutrition.