Upgrade to Pro — share decks privately, control downloads, hide ads and more …

Week 11 Videocast Slide Deck

DPC
October 30, 2020

Week 11 Videocast Slide Deck

DPC

October 30, 2020
Tweet

More Decks by DPC

Other Decks in Education

Transcript

  1. Examining Relationships Differences in measures of central tendency (means, medians,

    modes) Measures of association • Appropriate correlation analysis for level of measurement (i.e. nominal, ordinal, interval); Johnson, pg. 208 • Direction of relationship • Strength of relationship (correlation coefficient = r); Johnson, pg. 206 Crosstabs • Controlling for a third variable in crosstabs
  2. Detecting Relationships Analysis types Example criteria Differences between means or

    medians ✓ Found differences ✓ Controlling for rival explanations (confounding variables) Correlations ✓ Direction of relationship ✓ Strength of association (Johnson, pg. 206) Crosstabs ✓ 10% difference (or more) between groups (Johnson, pg. 199) ✓ Controlling for rival explanations (confounding variables) Statistical significance ✓ Alpha level
  3. Simple Regression = a + + e bx Y +

    b = mx Y intercept Regression coefficient Slope
  4. Simple Regression Simple Regression: Hours Studying & GPA Hours studying

    0.03 *** Constant (aka intercept) 0.04 R2 0.05 N 101 Note: ***p<0.01, **p<0.05, *p<0.10 Regression coefficient • Positive • Statistically significant Model fit • 5% of variance explained Intercept Number observations
  5. Multiple Regression Multiple Regression: Hours Studying & GPA Hours studying

    0.03 *** Classes attended 0.01 Hours partying -0.01** Constant (aka intercept) 0.06 R2 0.15 N 99 Note: ***p<0.01, **p<0.05, *p<0.10
  6. Indicates whether a finding can be generalized to a population,

    within a specified degree of confidence Statistical Significance The confidence level (chosen by the researcher) at which a finding is to be considered statistically significant 95% confidence level; a=0.05 90% confidence level; a=0.10 Alpha Level “Probability value,” or probability of a specific result, calculated for a specific result and compared with the chosen alpha level. P-Value If a calculated p-value falls below (is smaller than) the alpha level, the result in question is considered a statistically significant finding.
  7. Understanding Associations & Statistical Significance Association Statistical Significance Interpretation Strong

    Significant Relationship; Generalizable Strong Not significant Relationship; Not generalizable Weak Significant No/weak relationship; Generalizable Weak Not significant No/weak relationship; Not generalizable