Sta301 Quiz 3
1.
Consider
a large population with a mean of 160 and a standard deviation of 25. A random
sample of size 64 is taken from this population. What is the standard deviation
of the sample mean?
3.125….confirm
2.
In
sampling from a large population with 6=25. The size of the sample used is 10.
The value of the standard error will be
2
3.
In
general sample variance is a/an _______ estimator
Unbiased……confirm
4.
In
sampling from a large population with 6=60. The size of the sample used is 100
the value of the standard error will be
6
5.
If
the two populations are non-normal and both the sample sizes are large then the
sampling distribution of the difference of means will be
Normal
distribution
6.
The
larger the n the smaller the standard error and so the narrower the
Confidence interval…..confirm
7.
P 0
1 2 3 f(p) 1/20 9/20
9/20 1/20. The mean of the
sampling proportion will be
10/20
8.
The
sampling distribution of the mean becomes approximately normally distributed
only when the following conditions is met?
The sample size is
large……confirm
7. The standard error of the sampling
distribution of the sample mean when sampling is done with replacement is equal
to
9.
Which
one of the statement is true?
E(S2) is
not equal to s2
10. ________ is used
when we dealing with proportions to find the probabilities
Both z and t distribution
11.
A deserving player was not selected in the cricket team .it is an example of
Type-I error
12.
As sample size goes up, what tends to happen to 95 %confidence interval?
They become more precise and narrow
13.
A ………Is a range of number inferred from the sample that sample that has a certain
probability of including the population parameter over the long run.
Confidence interval
14.
A statistic whose standard error decreases with an increase in the sample
size will be…
consistent
15.
The precision of an estimator can be increased by decreasing the:
level of significance
16.
Conventionally, he probability of making a type-error is denoted by:
beta
17.
Sample mean is a .......... estimate of population mean.
Unbiased
18.
Conventionally, the probability of making a type-II error is denoted by:
Beta Lect
19.
Conventionally, the probability of making a type-I error is denoted by which of the
following symbol?
Alpha Lect
20.
Which of the following is most important and most widely used method in point
estimation?
The method of maximum likelihood
21.
If a statistic used as an estimator, has its expected value equal to the true value of
the population parameter being estimated then it is called........
Unbiased
22.
_________are equivalent
Type-I error and level of significance
23.
When sample size is to be considered large, population standard deviation
can be replaced by
Sample Standard Deviation
24.
A failed student was passed by the examiner”, is an example of:
Type-I error
25.
Sample mean is a .......... estimate of population mean.
Unbiased
26.
A standard deviation obtained from sampling distribution of sample statistics is
known as
Standard error
27.
A parameter is a____ quantity.
Variable
28.
How can we interpret 90% confidence interval for the mean of the normal
population?
There are 90%cahnces of falling true value of the parameter
29.
An industrial designer wants to determine the average amount of time it
taks an adult to assemble an “easy to assemble” toy. A sample of 16 times yielded an average time of 19.92 minutes, with a population standard deviation equal to 5.73 assuming
normality of assembly times. What is a 95%.
(17.1123, 22.7277)
30.
The larger the standard error, the ______ the confidence interval.
Wider
31.
Alpha is the probability of:
All of these
32.
A consistent estimator will always to a....
May or may not be unbiased estimator
33.
If var (TI) > Var (T2), where TI and T2 are two unbiased estimators, then:
TI is more consistent
34.
The mean of the sampling distribution of difference of means is represented by:
U1- u2
35.
Which of the following is not a criterion for a good problem situation?
It must be clearly structured and defined
36.
The method of maximum likelihood (ML) is used to find out:
Point estimates
37.
It is the probability of:
Reject HOI HO is true
38.
We can apply method of Maximum likelihood on:
Discrete as well as continuous variables
39.
To consider every possible value that the parameter might have, and for each
value, compute the probability and THAT value of the parameter for which the probability of a given sample is greatest, is chosen as an estimate.” This procedure is
known as
The method of maximum likelihood
40.
From which of the following methods we can obtain point estimate of the
population parameters:
All of the above
41.
The total number of samples when
sampling is done without replacement is equal to:
(N^n)
42.
The shape of the
Poisson distribution is:
Positively
43.
If mean of X2
distribution is k then variance will be:
2k
44.
If total
probability of joint probability distribution f(x, y) is ONE then what will be
the total probability of its marginal pdf h(y)?
One
45.
When we draw the
sample with replacement, the probability distribution to be used is:
Binomial & hypergeometric
46.
The proportion of
males in Pakistan is at least 0.48, the alternative hypothesis H1 is
P < 0.48
47.
Which of the
following is a measure of absolute dispersion?
Mean Deviation
48.
In sampling from
a large population with sigma = 35, the standard error of the mean is found to
be 4 next. The size of the sample used is:
56
49.
In hypothesis testing, suppose the critical value is |Z|
> 2.33. This value shows that the applied test is __________?
Two tailed test
50.
What factor
determines the shape of the t-distribution?
Degree
of freedom
51.
Which one is the
measure of central tendency:
Average
of the distribution
52.
Which statement
is true for a discrete Uniform distribution?
It
is absolutely symmetrical distribution.
53.
A good way to get
a small standard error is to use a __________.
Large
sample
54.
Value of harmonic
mean is lower than __________.
Both
arithmetic mean & geometric
55.
If a significance
level of 1% is used rather than 5%, the null hypothesis is:
More
likely to be rejected
56.
If P(X=x)=0, then
f(x) is a __________ probability function.
Discrete
57.
A fair coin is
tossed three times. What is the probability that at least one head appears?
44294
58.
Dividing mean
deviation by mean we get a pure number known as
Co-efficient
of mean deviation
59.
Suppose that a
sample space S consists of four simple events: A, B, C, and D. that is S = {A,
B, C, D}. If P(A) = .4, P(B) = .3, P© = .2, what is P(D)?
0.1
The
mean of the sampling distribution of x¯¯¯1−x¯¯¯2, denoted by μx¯¯¯1−x¯¯¯2is equal
to the difference between repective
PROPERTIES OF
THE SAMPLING
Which of the following statements is correct?
A point estimate is a single value estimate of the value of a
population parameter
In sampling without replacement; fpc is used when:
n=0.05N
The sampling distribution of the sample proportion, p^, will be
______ distributed if the sample size is large and p^ is not too close to 0 or
l:
Normal
Confidence interval is also known as
Margin of error
If P (6.2< ? <12.2) =0.95 then
95%
The relative efficiency of T1 compared to T2 where:
both T1 and T2 are unbiased estimators
As the sample size _____________ the variation of the sampling
distribution of the same means ______________:
Increases, remains the same
Thanks everone