To measure the effect on coordination associated with mild intoxication, thirteen subjects were each given 15.7mL of ethyl alcohol per square meter of body surface area and asked to write a certain phrase as many times as they could in the space of one minute (119). The number of correctly written letters was then counted and scaled, with a scale value of 0 representing the score a subject not under the influence of alcohol would be expected to achieve. Negative scores indicate decreased writing speeds; positive scores, increased writing speeds.

Use the signed rank test to determine whether the level of alcohol provided in this study had any effect on writing speed. Let α = 0.05. Omit Subject 8 from your calculations.

Subject Score Subject Score 8 10 910 4 -8 5 -6 12-10 2 13 20