Chi-Squared Test and P-Values

The teacher addresses errors in a biology assignment, providing a modified answer sheet. The video explains the use of mitotic index in chi-squared tests, discusses hypothesis testing, and clarifies observed vs. expected values. Misconceptions about cell cycle percentages are corrected, and final instructions on chi-squared test calculations are given.

What was the teacher's initial mistake in the assignment?

• Miscounting the number of cells

• Providing the wrong answer sheet

• Using the wrong mitotic index

• Incorrectly identifying cancerous tissue

What is the purpose of using a chi-squared test in this context?

• To differentiate between normal and cancerous tissues

• To determine the time spent in the cell cycle

• To calculate the mitotic index

• To count the number of cells in interphase

What is the degree of freedom in the chi-squared test for this activity?

• Zero

• Two

• Three

• One

What were the observed values for interphase and mitosis in the cancerous tissue?

• 20 interphase, 10 mitosis

• 17 interphase, 3 mitosis

• 13 interphase, 7 mitosis

• 15 interphase, 5 mitosis

What mistake did the teacher correct regarding the expected values?

• Incorrectly calculating the mitotic index

• Misidentifying cancerous tissue

• Using 40 cells in total

• Assuming 95% of cells are in interphase

What should the expected values be for interphase and mitosis?

• 17 interphase, 3 mitosis

• 13 interphase, 7 mitosis

• 15 interphase, 5 mitosis

• 20 interphase, 10 mitosis

What does a p-value greater than 0.05 indicate?

• Accept the alternative hypothesis

• Reject the null hypothesis

• Accept the null hypothesis

• Reject the alternative hypothesis

What was the teacher's mistake regarding the number of cells to use?

• Using 20 cells instead of 10

• Using 30 cells instead of 20

• Using 40 cells instead of one set

• Using 50 cells instead of 40

What is the significance of a p-value less than 0.05?

• It supports the null hypothesis

• It indicates a calculation error

• It supports the alternative hypothesis

• It suggests more data is needed

What should students do if they still have questions?

• Rewatch the video

• Ignore the confusion

• Ask questions on Remind

• Consult a textbook