Quantitative Methodscoin Toss Simulationname: ______

Quantitative MethodsCoin Toss SimulationName: ______

MA 103, Section 01

Name: ______

Activity 18.1

1. Toss a coin 10 times, and after each toss record in the following table the result of the toss and the proportion of heads so far. For example, consider the sequence of tosses: H T T T H.
After the first toss, the proportion of heads was 1/1, after the second toss the proportion of heads was 1/2, then after the third toss it was 1/3, 1/4 after the fourth, and finally 2/5 after the fifth toss.

2. On the following axes, plot the proportion of heads so far, for each toss from your table. What does your graph show?

Initially graph varies with steep rise but as no of flips increases, it starts approaching ½ which is in accordance with law of large numbers.

3. If you wanted to simulate coin tossing in Excel, you could use its =rand() function. rand() produces a random decimal number between 0 and 1. So if we generate a random decimal which is between 0 and 1, and multiply it by 2, the result is between 0 and 2. Then we could take the integer part of this number to get either a 0 or a 1. We can let the 0 represent a “tails,” and 1 represent a “heads.”

So, if rand() generates 0.13061, what value is produced when you multiply it by 2 and take the integer part?

So, if rand() generates 0.7893, what value is produced when you multiply it by 2 and take the integer part?

When rand() generates 0.13061 value is 0
When rand() generates 0.78934 value is 1

4- Write a paragraph explaining what your graph shows

The graph shows that proportion is close to 1/2 as the number of the coins increases which is in accordance with the law of large numbers.

5.Put the cursor in any blank cell near your graph. Press Ctrl= to change the

random numbers and your graph. Do this several times and describe how the

graph changes.

The proportion of head changes quite drastically for the first 10 observations when we refresh the graph but the overall probability still remains at .5. There should be enough sample size to check this.

6. Shaquille O'Neal is not particularly good at free throws. He makes about

50 percent of his free throws over an entire season.

a.Go to sheet 2 and set up a new worksheet to simulate 100 free throws shot

independently by a player who has probability 0.5 of making each shot. In

column A, keep a record of the attempt number by generating integers 1,

2, . . . , 100 in cells A2 through A101. (Enter an appropriate title in cell A1.)

b. Label cell B1 Hit or Miss and generate a random sequence of 1s (each 1

represents a hit) and 0s (each 0 represents a miss) in cells B2 through B101.

c. Compute the overall proportion of hits by calculating the mean of the

B column values. Also look at your data and identify the length of the

longest streak of hits and the length of the longest streak of misses.

Write a paragraph commenting on the proportion of hits and the "streaks."

length of the longest streak of hits – 8

length of the longest streak of misses. – 10

The probability reaches near the value 0.49 in this case which comes close to 0.5 as no of population increases. There is variation in good streak of hitting the shots but when it is averaged out over large population, probability comes close to 0.5.

7. A certain college's men's basketball team is quite accomplished at making free

throws. According to the coach, in their most recent season the team made

approximately 75 percent of free-throw attempts, and ranked 10th in the country

among similar schools in successful free-throw attempts.

a. Set up another new worksheet to simulate 100 free throws shot by team

members who have probability 0.75 of making each shot.

b. Again, use column A to keep track of the attempt number in cells A2

through A101.

c. Label cell B1 Hit or Miss. Now you will generate a sequence of equally

likely occurrences of the numbers 0, 1, 2, or 3 with 0 representing a

miss and any of the other three numbers representing a hit. By entering

the formula =INT(4*RAND()) into cell B2, you can set the sequence up

so each of the numbers occurs with equal probability. Then autofill to

cell B101.

d. In cell C2, enter the formula =IF(B2=0,0,1). This will give you a "1" in cell

C2 if cell B2 recorded a hit, and a "0" if cell B2 recorded a miss. Autofill

the formula down to cell C101.

e. Find the overall proportion of hits, and identify the length of the longest

streak of hits and the length of the longest streak of misses. Write a paragraph

commenting on your proportion of hits and your "streaks."

length of the longest streak of hits – 9

length of the longest streak of misses. – 3

f. Describe how the "streaks" compare for the 50-percent and 75-percent

scenarios.

As compared to 50% hitting team, 75% hitting team has more probability of hitting the team and less streak of missing.