Final answer:
To investigate the relationship between the number of media exposures to negative news stories within a 24-hour period and individuals' mood levels, a correlation analysis, such as Pearson's correlation coefficient, would be appropriate.
Step-by-step explanation:
In the realm of statistical analysis, correlation measures the strength and direction of a linear relationship between two variables. For this study, the null hypothesis
would posit that there is no significant correlation between the number of media exposures to negative news stories and individuals' mood levels.
Mathematically, this can be expressed as
, where
represents the population correlation coefficient. The alternative hypothesis
, on the other hand, would suggest that there is a significant correlation, and it can be stated as

The correlation coefficient ranges from -1 to 1, where -1 indicates a perfect negative linear relationship, 1 indicates a perfect positive linear relationship, and 0 indicates no linear relationship.
After conducting the correlation analysis, if the p-value associated with the correlation coefficient is less than the chosen significance level (commonly 0.05), we would reject the null hypothesis and conclude that there is a statistically significant relationship between media exposures to negative news stories and individuals' mood levels. This approach allows researchers to quantitatively assess the strength and direction of the potential link between these variables.
In summary, the chosen statistical method, in this case, is correlation analysis, and the null hypothesis posits no correlation
, while the alternative hypothesis suggests a significant correlation
