STA301 Final Term Solved Subjective by Moaaz

Solved Subjective · From Final term Papers · Feb 16,2013 · PSMD01

1A sample of size n=3 drawn without replacement experiment from a population N=5 items whose values 0,2,3,6,7 draw possible samples

Sample without replacement = N n (0,2,3), (0,2,6), (0,2,7), (0,3,6), (0,3,7), (0,6,7), (2,3,6), (2,3,7), (2,6,7), (3,6,7).

2- Calculate sampling error if sample mean is 102 and population mean is 100

Answer: (Page 14) X

3- Define Unbiased estimator

Answer: (Page 258) An estimator is defined to be unbiased if the statistic used as an estimator has its expected value equal to the true value of the population parameter being estimated. E 

4- Quartile deviation

Answer: (Page 84) The quartile deviation is defined as half of the difference between the third and first quartiles. Q Q Q D

Q1. decribe about significance level

Answer: The significance level is the criterion used for rejecting the null hypothesis. It show you how likely a result is due to chance. The most frequently used values of α, the significance level, are 0.05 and 0.01, i.e. 5 percent and 1 percent.

Q2. discuss about center limit theorem

Answer: (Page 243) “If a variable X from a population has mean μ and finite variance σ/2, then the sampling distribution of the sample mean⎯X approaches a normal distribution with mean μ and variance σ2/n as the sample size n approaches infinity.”

Q3. What is difference between constant and random variable

Answer: A variable whose value cannot be changed once it has been assigned a value while those variable whose values changes when we assign value to it.

Q: Define an Un-Biased estimator? 2 Marks

Answer: Rep

Q: Briefly Explain an experiment design? 2 Marks

Answer: (Page 320) By an experimental design, we mean a plan used to collect the data relevant to the problem under study in such a way as to provide a basis for valid and objective inference about the stated problem.

Q: Define an independent and dependent variable in regression? 2 Marks

Answer: (Page 121) In regression Y represents the dependent variable and X represents the independent variable

What is the difference between an outcome and an event? (2)

Answer: (Page 145) An outcome is a result of a single trial of an experiment while an event is an individual outcome or any number of outcomes.

The mean of a Poisson distribution is 5 while its standard deviation is 4. Comment on it (2)

Answer: (Page 223) In Poisson distribution mean and variance are always equal but this statement is not satisfying this property of Poisson distribution.

If an automobile is driven on the average no more than 16000 Km per year, then formulate the null and alternative hypothesis. (2)

Answer: 16000 16000 H H

Q: Discuss three properties of normal distribution? 3 Marks

Answer: (Page 227) Normal distribution is absolutely symmetrical, hence ,  the third moment about the mean is zero The normal curve is asymptotic to the x-axis as x → ± ∞. For the normal distribution, it can be mathematically proved that

Q: The 90% confidence interval for the population mean is 11 to 20, interpret this result? 3 Marks

Answer: We are 90% sure that our Population mean lie between 11 – 20.

Q: Define LSD test? 3 Marks

Answer: (Page 330) According to this procedure, we compute the smallest difference that would be judged significant, and compare the absolute values of all differences of means with it. This smallest difference is called the least significant difference or LSD. And is given by

v MSE LSD t r