BIOL 190 Lecture Notes - Lecture 27: Punnett Square, Genotype, Lentil

• School: University of San Diego
• Department: Biology Courses
• Course: BIOL 190
• Professor: Leavitt, Dean

Document Summary

Goodness of t test (x^2 or chi squared test) Degrees of freedom: how complex a model is df = n- 1: where n is number of classes or categories. Critical values: will usually use alpha = . 05. If a chi-squared results in value greater than critical value, we reject our model. Chi squared of boys for my data: . 02. Chi squared of girls for combined data: . 16. Sum: . 32 (sum is obtained by adding both chi squared values) Since our results are less than our critical value, we fail to reject our original model. If we have an organism with 69 hairless offspring and 31 hairy offspring. What is the chi-square value? (expected 75 to 25) Since alpha = 3. 84 (df = 1, 2 phenotypes) and our chi-square value is less than that, we fail to reject our original model. What if one allele should have been lethal (expected 66. 7 to 33)