Is the data consistent with the model?

In general, it's a good idea to use two-tailed p-values, which you have calculated like this:

# Compute two-tailed p-value
null %>%
  summarize(pval = 2 * mean(stat <= d_hat))

In the case of the chi-squared, however, you compute only the right tail, which makes it a one-tailed test. This is the tail with statistics that are more common when the hypothesis of independence is false.

Using the objects that you created in the previous exercise (null_spac, null_arms, chi_obs_spac, and chi_obs_arms), compute the p-values of these two hypothesis tests and use them to select the correct answer below. Note that you'll have to tweak the code above to be sure to include only the right (greater than) tail in your p-values.

Possible answers

Since both p-values are above 0.05, we fail to reject the hypotheses that both military spending and spending on space exploration are independent of political party.

The dataset is consistent with the hypothesis that there is no relationship between political party and space exploration spending, but does suggestion a relationship between party and spending on the military.

The dataset is inconsistent with the hypothesis that there is no relationship between both military spending and party as well as spending for space exploration and party.

The dataset is consistent with the hypothesis that there is no relationship between political party and military spending, but does suggestion a relationship between party and spending on space exploration.

Exercise

Is the data consistent with the model?

Instructions

Possible answers