The article “Can We Really Walk Straight?” (Amer. J. of Physical Anthropology, 1992: 19–27) reported on an experiment in which each of 20 healthy men was asked to walk as straight as possible to a target 60 m away at normal speed. Consider the following observations on cadence (number of strides per second): Use the methods developed in this chapter to summarize the data; include an interpretation or discussion wherever appropriate. [Note: The author of the article used a rather sophisticated statistical analysis to conclude that people cannot walk in a straight line and suggested several explanations this.]

Answer : Step 1 : Consider the following observations on cadence (number of strides per second): 0.95 0.78 0.85 0.93 0.92 0.93 0.95 1.05 0.93 0.93 0.86 1.06 1 1.06 0.92 0.96 0.85 0.81 0.81 0.96 Sum 18.51 Begin by computing mean and standard deviation of the given data. Use the formula for the mean ,noting that there are 20 observation. So we have to find mean. The formula of the mean is xi x = n Substitute the value i = 18.51 and n=20. x = 18.51 20 x = 0.9255 Therefore mean is 0.9255 Now we have to find the standard deviation. 2 x (x x) x (x x)2 0.95 0.00060025 0.78 0.02117025 0.85 0.00570025 0.93 2.025E-05 0.92 3.025E-05 0.93 2.025E-05 0.95 0.00060025 1.05 0.01550025 0.93 2.025E-05 0.93 2.025E-05 0.86 0.00429025 1.06 0.01809025 1 0.00555025 1.06 0.01809025 0.92 3.025E-05 0.96 0.00119025 0.85 0.00570025 0.81 0.01334025 0.81 0.01334025 0.96 0.00119025 2 (x x) = 0.124495 The formula of the standard...