1 / 7

Nested Design

Nested Design. Comparison of 2 Shampoo Formulations on Hair Combability M.L. Garcia and J. Diaz (1976). “Combability Measurements on Human Hair,” Journal of the Society of Cosmetic Chemists , Vol.27 pp.379-398. Data Description. 2 Formulations of Shampoo (A and B)

pekelo
Télécharger la présentation

Nested Design

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. Nested Design Comparison of 2 Shampoo Formulations on Hair Combability M.L. Garcia and J. Diaz (1976). “Combability Measurements on Human Hair,” Journal of the Society of Cosmetic Chemists, Vol.27 pp.379-398

  2. Data Description • 2 Formulations of Shampoo (A and B) • 16 Hair Swatches Prepared (8 for A, 8 for B) • 5 Test Runs Made per Swatch (Replicates) • Combability Measurements made before and after shampooing (we consider only AFTER here) • Shampoo Treated as FIXED Factor, Swatch RANDOM • N=2x8x5=80 Measurements

  3. Statistical Model Note: For Computational purposes, we will label the swatches 1,…,16 and not 1,…,8 separately for each shampoo

  4. Data

  5. Summary Statistics

  6. Sums of Squares

  7. ANOVA – Tests of Factor Effects H0: a1 = a2 = 0 HA: a1≠ a2 T.S.: FForm = 0.112 (P=0.7390) Conclude no formulation differences on combability H0: sb2 = 0 HA: sb2> 0 T.S. FSwatch(F) = 9.43 (P=.0000) Conclude Swatch effects vary with respect to combability

More Related