1. All forms of intoxication significantly increase collisions, biggest impact from alcoholic beer.
2. Positive and linear relationship: more intoxicant, more collisions.
3. Difference between alcoholic beer and water: 2.5 to 8.3 more collisions (95% confidence).
Question 1: What was the outcome of the study and how strong was the effect?
The outcome of the study was that all forms of intoxication led to a significant increase in the number of collisions compared to the control group (water). The effect was strongest for alcoholic beer, followed by marijuana beer and then water. This can be seen in the data, where the average number of collisions for the alcoholic beer group is 6.8, compared to 4.0 for the marijuana beer group and 2.7 for the water group.
Question 2: What is the nature of the relationship?
The relationship between intoxication and collisions is positive and linear. This means that as the level of intoxication increases, the number of collisions also increases. This can be seen in the graph, where there is a clear upward trend in the data.
Question 3: What are the confidence intervals for the differences between group means?
We can calculate confidence intervals to estimate the range of values within which the true difference between the group means is likely to fall. For example, the 95% confidence interval for the difference between the means of the alcoholic beer and water groups is (2.5, 8.3). This means that we are 95% confident that the true difference between the means of these two groups is somewhere between 2.5 and 8.3 collisions.
This study provides strong evidence that all forms of intoxication lead to a significant increase in the number of collisions in a driving simulator. The effect is strongest for alcoholic beer, followed by marijuana beer and then water. The relationship between intoxication and collisions is positive and linear, meaning that as the level of intoxication increases, the number of collisions also increases.
Here are some additional details that you may find helpful:
The sample size for each group is small (n = 6), so the results of this study should be interpreted with caution.
The study does not control for other factors that could affect driving performance, such as fatigue or distraction.
The study only used a driving simulator, so it is not clear how generalizable the results are to real-world driving.
Overall, this study provides a valuable starting point for understanding the effects of intoxication on driving performance. However, more research is needed to confirm these findings and to determine the specific mechanisms by which intoxication impairs driving skills.