Question

Athletes performing in bright sunlight often smear black eye grease under their eyes to reduce glare. Does eye grease work? In one study, student subjects took a test of sensitivity to contrast after three hours facing into bright sun, both with and without eye grease. Greater sensitivity to contrast improves vision and glare reduces sensitivity to contrast. This is a matched pairs design. The differences in sensitivity, with eye grease minus without eye grease is given.

Diff
0.07
0.64
-0.12
-0.05
-0.18
0.14
-0.16
0.03
0.05
0.02
0.43
0.24
-0.11
0.28
0.05
0.29

Differences in sensitivity, with eye grease minus without eye grease To access the complete data set, click the link for your preferred software format: Excel Minitab JMP SPSS TI R Mac-TXT PC-TXT CSV CrunchIt!

How much more sensitive to contrast are athletes with eye grease than without eye grease? Give a confidence interval to answer this question. (Enter your answers rounded to four decimal places.)

Lower bound =

Upper bound =

Answer 1

conside the cbove given hat by using Softasane foinat he staliskical Software out put Confidence inteval esul is lowey uPfer DF bound bound Vastiable Sanple Std eror nean 0-2679 data IS-0 0658 O OS6S823 Hence Sanple mean = olo12 Standa esO = o.OS6S uPpest bound O 2680 lowe bound - -O.06SS