1 / 16

EPE/EDP 557

EPE/EDP 557. Key Concepts / Terms Empirical vs. Normative Questions Empirical Questions Normative Questions Statistics Descriptive Statistics Inferential Statistics Populations & Samples Population Parameter Sample Statistic

cher
Download Presentation

EPE/EDP 557

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. EPE/EDP 557 • Key Concepts / Terms • Empirical vs. Normative Questions • Empirical Questions • Normative Questions • Statistics • Descriptive Statistics • Inferential Statistics • Populations & Samples • Population • Parameter • Sample • Statistic • Hypothesis: statement positing a relationship among variables • Null-hypothesis • Research-hypothesis (or working hypothesis)

  2. EPE/EDP 557 • Key Concepts / Terms • Variable: concept, characteristic, or state of being that can vary from one observation to another • Nominal: attributes • Ordinal: ranks or orders • Interval: consistent numeric scale with arbitrary zero • Ratio: consistent numeric scale with meaningful zero • Distribution: arrangement/listing of a set of scores in order of magnitude • Frequency Distribution: listing of achieved scores in order of magnitude & corresponding listing of the number of occurrences of each score

  3. Distribution 100 90 90 80 70 70 70 60 50 50 Frequency Distribution X f 100 1 90 2 80 1 70 3 60 1 50 2 EPE/EDP 557

  4. EPE/EDP 557 • Central Tendency • Mean (M): simple average • e.g. 3, 4, 4, 5, 9 • ΣX = 3 + 4 + 4 + 5 + 9 = 25 • N = 5 • 25 ÷ 5 = 5 • Median (Mdn.): middle score • If N is odd, use middle score • If N is even, take average of 2 middle scores • Mode (Mo.): most frequent score(s)

  5. EPE/EDP 557 • Central Tendency • Skewed Distribution: distribution unbalanced by extreme scores in one direction

  6. EPE/EDP 557 • Central Tendency • Skewed Distribution:

  7. EPE/EDP 557 • Bar Graphs, Histograms, & Frequency Polygons • Bar Graph:

  8. EPE/EDP 557 • Bar Graphs, Histograms, & Frequency Polygons • Histogram:

  9. EPE/EDP 557 • Bar Graphs, Histograms, & Frequency Polygons • Frequency Polygon:

  10. EPE/EDP 557 • Variability: • describe the degree to which scores are spread out / dispersed • provide information about how scores differ (vary) • 3 major measures of variability: • Range (R) • Variance (V) • Standard Deviation (SD)

  11. EPE/EDP 557 • Measures of Variability: • Range: • Simplest measure of variability • Range = highest score – lowest score • Fractiles: • Used to locate specific points in a distribution • Not actual measures of variability, but…

  12. EPE/EDP 557 • Measures of Variability: • Standard Deviation: • The “Heart & Soul” of the concept of variability • Provides information on the average deviation of scores from the mean in a distribution • Sample Standard Deviation: or

  13. SD Deviation Method EPE/EDP 557

  14. EPE/EDP 557 • SD Computational Method

  15. EPE/EDP 557 • Variability (Dispersion) • Variance: Provides information on how far all of the scores in a distribution deviate from the mean

  16. EPE/EDP 557 • Variability: • Kurtosis: the degree of curvature of a unimodal distribution of scores • Flat = Platykurtic (below left) • Peaked = Leptokurtic (below right)

More Related