In: Statistics and Probability
Without external cues such as the sun, people attempting to walk in a straight line tend to walk in circles. It has been suggested that this tendency is due to internal asymmetries between individuals, or that individuals' legs differ in length or strength.
Souman et al. (2009) tested for differences in individuals'
tendencies to change direction by blindfolding 15 participants and
asking them to walk in a straight line in an empty field. The
numbers in this dataset represent median change in direction (or
turning angle) of each of the 15 participants, measured in degrees
per second. Negative angles = left turns; positive angles = right
turns.
Begin by producing a frequency distribution graph of the dataset
for yourself.
1.28457373 |
0.7491364 |
-2.2991328 |
-1.5565737 |
0.29162495 |
-0.563625 |
2.02713279 |
2.02713279 |
-0.136 |
-0.563625 |
0.29162495 |
1.28457373 |
2.02713279 |
2.02713279 |
0.7491364 |
Begin by producing a frequency distribution graph of the dataset for yourself.
Do the data appear to be normally distributed? Answer "yes" or "no"
No
Based on the graph, do people tend to turn in one direction more than the other? Answer "right" or "left"
Right
Is this a one- or two-tailed t test? (enter either 1 or 2 for your answer)
Two-tailed t-test
Conduct a one-sample t-test. What is your calculated t-value? Answer to 2 decimal places, and include leading zeros:
0.0000000 | hypothesized value | |
0.5093497 | mean Data | |
1.3496309 | std. dev. | |
0.3484732 | std. error | |
15 | n | |
14 | df | |
1.462 | t | |
.1659 | p-value (two-tailed) |
calculated t-value = 1.46
Does the mean angle differ significantly from zero? "yes" / "no"
No
Based on your test, is the following statement justified? "People do not have a tendency to turn more in one direction, on average, than the other direction." "yes" / "no"
No