Statistics / Business Mathematics / Quantitative Analysis for Decision Making - MBA

[yousuf.zahid]

Correlation, Standard Deviation, Regression, Probability, Hypothesis...

Whatever you crave for, you'll find in the books presented here. Though we had a different book prescribed to us but I had used these to practice and hard core practice is what you'll get from these.

Students of econometrics may also find it useful.

The book by Weiers is really good with easy to understand theory. Chiang's book also comes with an answer-key.

Its not an easy subject to master but these books will help you in grasping the concepts. Trust me, eventually in professional life, you'll one day ask your team to calculate the competing brand's standard deviation over the last quarter. ;)

Read with a passion to learn!

PS. Use WinRAR and when extracting Fundamental Methods of Mathematical Economics, just extract "part 1" and the entire book will consolidate and appear.

[shweta666]

Hi Yousuf Zahid,
Is it possible for you to share some of the probability questions or papers for extra practise...
As these are such types of questions which makes it tuff...
Can you please share it...?

[yousuf.zahid]

Yes Shweta, I do have some questions on probability that I got for quizzes and exams. Since that was from a different semester so I'll have to check where they're buried. But I'll put them up here.

[yousuf.zahid]

Sometimes if you look at the place where you oughta have looked first then you get what you want.

I found a quiz on probability in the course book. Since my study's a mess - everything's there - just needs time to locate. Lol!

Got 2/5 in this one. I never could get a grip over probability, estimations and hypothesis. Anyhow, I'll search for the two assignments that we got. Had good questions in it. Hope the following helps. Will keep this thread updated.

Q1. An urn contains 6 red and 5 blue balls, find the probability of drawing a blue ball.

Q2. In one of the classes it is known that 60% of the students are girls and 20% are below 58 inches tall, while 30% are boys or 58 inches taller. What is the probability that a student at random selected from this class is a boy at at least 58 inches tall.

Q3. Three digit numbers are formed from the digits 2, 3, 4, 5, 6, 7 and 8, each digit is used only once. What is the probability of:

a. An odd number
b. An even number greater than 400
c. A number greater than 650

Q4. Two dice are rolled simultaneously and the product of the numbers that occur is determined, what is he probability that the product would be:

a. Less than 30
b. A prime number excluding 1
c. A perfect square

[shweta666]

Sometimes if you look at the place where you oughta have looked first then you get what you want.

I found a quiz on probability in the course book. Since my study's a mess - everything's there - just needs time to locate. Lol!

Got 2/5 in this one. I never could get a grip over probability, estimations and hypothesis. Anyhow, I'll search for the two assignments that we got. Had good questions in it. Hope the following helps. Will keep this thread updated.

Q1. An urn contains 6 red and 5 blue balls, find the probability of drawing a blue ball.

Q2. In one of the classes it is known that 60% of the students are girls and 20% are below 58 inches tall, while 30% are boys or 58 inches taller. What is the probability that a student at random selected from this class is a boy at at least 58 inches tall.

Q3. Three digit numbers are formed from the digits 2, 3, 4, 5, 6, 7 and 8, each digit is used only once. What is the probability of:

a. An odd number
b. An even number greater than 400
c. A number greater than 650

Q4. Two dice are rolled simultaneously and the product of the numbers that occur is determined, what is he probability that the product would be:

a. Less than 30
b. A prime number excluding 1
c. A perfect square

Thanks Yousuf,
Is it possible to post their answers and along with it post some more new questions and upload some more of the pdf file.

[yousuf.zahid]

Yes I've the other quizzes with me since I don't throw anything away. (But am not a hoarder...lol). This course was like N-1 I think so three quizzes more, one's definitely on the dreadful Hypothesis.

Plus those assignments - two of them - that we got.

But I wouldn't be able to post the answers since these were quizzes and solved and submitted in class. To solve them all over again would require motivation which has now been mustered for the current semester. Hey! At least I get a point for being honest. Lol!

But if you do group study then you're bound to come up with the solution. Besides if your teacher is cooperative then he/she can help you out anytime.

[yousuf.zahid]

Guys...jotting down the two comprehensive assignments. Hope it provides you good practice.

Assignment 1

Q1. Given below are the weekly wages in dollars [Y] and the number of hours worked [X] by a group of 11 semi-skilled workers.

Y: 55 65 70 60 65 70 75 75 70 80 72
X: 35 42 45 38 40 44 45 48 46 50 47

a. Determine the values of mean, median and mode for each of the two series. Interpret your result.
b. Determine the standard deviation of each series and interpret your result.
c. What percent of observations in each series fall with in 2 standard deviation of the mean?
d. Comment using some suitable measure about consistency and skewness of each of the two series.

Q2. For the data given in question 1 above, construct an appropriate regression to predict the wage of a worker who worked for 52 hours in a week. Also:

a. Interpret the slope and the intercept of the equation.
b. Determine the values for r and r2 [i.e. r square] and interpret your results.

Q3. Define and explain partial and multiple correlation. Given r12 = 0.6, r13 = -0.6 and r23 = -0.7 determine r13.2 and r1.23

[yousuf.zahid]

And here's the other...

Assignment 2

Q1. Obtain an equation which describes Gross Private Domestic Investment [Y] as a function of Gross Domestic Product [X], both in trillion dollars.

Y: 0.828 0.863 0.815 0.738 0.790 0.863 0.975 0.996 1.084 1.206
X: 5.865 6.062 6.136 6.079 6.244 6.389 6.610 6.761 6.994 7.269

Also determine the value of r-square.

Q2. In a sample of 800 Toshiba dry batteries, 100 are found to be spoiled. Test at 5%, whether more than 10% of the batteries in the population are spoiled.

Q3. In a sample of 850 men from Deira, Dubai, 265 are found to be smokers. In another sample of 650 women from the same area, 180 are found to be smokers. Test at 1%, whether there exists any difference in the proportion of smokers among men and women.

Q4. Mangoes are exported in specific sized cartons by two suppliers, X and Y. A sample of 21 cartons from X's shipment was found to weigh 16.5 kg on the average with a standard deviation of 3.5 kg. Another sample of 11 cartons from Y's shipment was found to weigh 19 kg on the average with a standard deviation of 2.5 kg.

a. Test at 2% whether the population variances are equal.
b. As a consequence of the result obtained in 'a' above:
i. Test at 5% whether the average weight in X's cartons falls short of Y's.
ii. Construct a 95% confidence interval for the difference in their mean weights.

Q5. In a sample of 600 boys, 22 percent are found to have earned more than 55 percent marks in statistics. In another sample of 500 girls, 15 percent are found to have earned more than 55 percent marks in the same course. Construct a 95% confidence interval for the difference in the proportion of boys and girls earning more than 55 percent marks in the population.

Q6. The waiting time for take-off in minutes for departing aircraft at Heathrow are assumed to be normally distributed with a mean of 24 minutes and a standard deviation of 8 minutes. What is the probability that the plane you are boarding will take:

a. At least 35 minutes.
b. At most 30 minutes.
c. What is the waiting time of the 12 percent lowest waiting planes?
d. What is the waiting time of the 15 percent highest waiting planes?

[yousuf.zahid]

And I found another quiz that we had on Correlation...

Question. Given below is a demand schedule for eggs, where the price is in rupees per dozen and the quantity of eggs that would be demanded at the stated prices, in thousand dozens.

Price: 15 17 18 20 22 25 30
Quantity: 38 37 35 30 26 24 20

a. Determine the correlation coefficient between price and quantity.
b. How the correlation coefficient would be effected if price is expressed in dollars and the quantity in baskets of 20 dozen eggs each.
c. Use an appropriate regression to predict the price, when the quantity demanded is 40,000 dozens.
d. At what price the demand would vanish?

[masoom]

Sometimes if you look at the place where you oughta have looked first then you get what you want.

I found a quiz on probability in the course book. Since my study's a mess - everything's there - just needs time to locate. Lol!

Got 2/5 in this one. I never could get a grip over probability, estimations and hypothesis. Anyhow, I'll search for the two assignments that we got. Had good questions in it. Hope the following helps. Will keep this thread updated.

Q1. An urn contains 6 red and 5 blue balls, find the probability of drawing a blue ball.

Q2. In one of the classes it is known that 60% of the students are girls and 20% are below 58 inches tall, while 30% are boys or 58 inches taller. What is the probability that a student at random selected from this class is a boy at at least 58 inches tall.

Q3. Three digit numbers are formed from the digits 2, 3, 4, 5, 6, 7 and 8, each digit is used only once. What is the probability of:

a. An odd number
b. An even number greater than 400
c. A number greater than 650

Q4. Two dice are rolled simultaneously and the product of the numbers that occur is determined, what is he probability that the product would be:

a. Less than 30
b. A prime number excluding 1
c. A perfect square

Can you please post the answers for the above.
Not really able to get it..