Statistics Essay

2216 Words Mar 3rd, 2015 9 Pages
General Lectures 1-4 What is statistics? Discipline: collecting, classifying, summarizing, organizing, analyzing and interpreting numerical information. -A means to answer research questions (and to test hypothesis). -No scientific proof: make plausible through empirical data with an empirical observed result. Shape and skewness:  Negatively skewed: mean < median  Symmetry: mean = median  Positively skewed: mean > median Mode = the score that occurs most frequently. Median = middle score when scores are ranked in order. Mean = the average score, the media. Interpreting the standard deviation: -the empirical rule (frequency distribution is bell shaped and symmetric)  68% values: -1 - +1  95% values: -1 - +1  99.7 % values: …show more content…
Alternative hypothesis: H1 - Represents the assumption tested: effect; difference; correlation, the researcher’s expectation with respect to changes in this situation.

1

Video Lecture 1 Descriptive questions: data Describing population characteristics  Characteristics of data: central tendency



Characteristics of data: variability/dispersion

1. Measure of central tendency and measure of variability: the most adequate measure of central tendency is the mode and there is no adequate measure of variability (decision/claim). The choice for these measures is founded on the fact that the variable X is of nominal measurement level (data/ground). On nominal level the mode is the only adequate summary measure and there is no adequate measure of variability (warrant). Interpretation: The X sector has the highest number of … This is because the mode lies in this sector. The mode determines the sector with the highest frequency.

2. Measure of central tendency and measure of variability: the most adequate measure of central tendency is the mean and the most adequate measure of variability is the standard deviation (decision/claim). The choice for these measures is founded on the fact that the variable is of ratio measurement level (data/ground). On ratio level the most adequate summary measure is the mean and the most adequate measure of variability is the standard deviation (warrant). Interpretation: The mean… is about ... We expect that (at least) 75%

Related Documents