PS101 Lecture Notes - Lecture 4: Standard Deviation, Null Hypothesis, Dependent And Independent Variables
Document Summary
Analyzing data: two kinds of statistics, descriptive. Descriptive statistics: used to give basic information about what we find, a summary, the mean, the standard deviation, the range known as the measure of central tendencies. Variability: how spread out scores are from the mean. Little variability bunched up close to the mean. Lots of variability wide curve: standard deviation is an index score based on the distribution, tells where, in relation to the general plot scores, the score falls. Measures of central tendencies: mean = (cid:862)average(cid:863, median = middle score, mode = most commonly or frequently occurring score. Correlation: gives us the correlation between two variables but does not give cause and effect. Increase in one variable and a decrease in another: examples: exercise and depression, hours per week of tv and gpa. September 19, 2017: seems sensible that study time predicts performance, these things co-occur, one does not necessarily cause the other.
