chi-squared test

• What statistical method is discussed in the video?

  Chi-squared
• When would you use the chi-squared statistic?

  To investigate differences in frequency data
• What is the cause of cystic fibrosis?

  Recessive allele
• What is the probability of two heterozygous parents having a girl with cystic fibrosis?

  12.5 percent
• How is the probability of having a girl with cystic fibrosis calculated?

  Multiply by 50 percent after punnett square
• What does chi-squared help to compare?

  Expected frequency and observed frequency
• What is the process to use chi-squared in inheritance questions?

  1. Use punnett square for expected frequency
  2. Record actual observed frequency
  3. Calculate chi-squared statistic
  4. Compare chi-squared value to critical value
• What is the total number of corn kernels counted?

  34 kernels
• How is the expected frequency calculated from the total kernels?

  Multiply total by expected ratio
• What critical value is used for the chi-squared test at p=0.05?

  3.841
• What conclusion can be drawn if the chi-squared value is less than the critical value?

  Accept the null hypothesis
• What does accepting the null hypothesis imply about the corn kernels?

  They follow the expected 3 to 1 ratio
• How does chi-squared support Mendelian genetics?

  • Compares expected ratios to observed data
  • Validates Mendelian inheritance patterns
  • Demonstrates statistical significance in results