What will be the 't value' when 'between-groups variance' and 'within-groups variance' is 200 and 50 respectively ?
2
4
8
16
Difficulty Level: 1
Positive Marks: 1.00
Negative Marks: 0.33
Consider a set of 18 samples from a standard normal distribution. We square each sample and sum all the squares. The number of degrees of freedom for a Chi Square distribution will be?
17
18
19
20
Difficulty Level: 1
Positive Marks: 1.00
Negative Marks: 0.33
What is the expected value of the binomial distribution where n = 16 and p = 0.85 ?
6
7.4
12.4
13.6
Difficulty Level: 1
Positive Marks: 1.00
Negative Marks: 0.33
Consider a random variable X that takes values +1 and −1 with probability 0.5 each. The values of the cumulative distribution function F(x) at x = −1 and +1 are
0 and 0.5
0 and 1
0.5 and 1
0.25 and 0.75
Difficulty Level: 1
Positive Marks: 1.00
Negative Marks: 0.33
If A and B are two events such that P(A⋃B) = 5/6, P(A⋂B) = 1/3, P(B) = ½, then the events A and B are
dependent
Independent
Mutually exclusive
none of the above
Difficulty Level: 1
Positive Marks: 1.00
Negative Marks: 0.33
Suppose that X is a continuous random variable with probability density function given by:

3
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
In a tree, there are hundreds of apples. You are randomly choosing 46 apples with a mean of 86 and a standard deviation of 6.2. Determine that the apples are big enough.
((84.21,87.79))
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
A certain drug is to be rated either effective or ineffective. Suppose lab results indicate that 75% of the time the drug increases the lifespan of a patient by 5 years (effective) and 25% of the time the drug causes a complication which decreases the lifespan of a patient by 1 year (ineffective). As part of a study you administer the drug to 10000 patients.

Choose the correct options:

Expected value of change in lifespan of a single patient is 5.5.
Standard deviation of change in lifespan of a single patient is 0.026
Only B is correct.
None is correct.
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
If the mean value for the weight of 25 men was calculated to be 90 kg with a standard deviation of 10 kg, what would the 95% confidence interval for the mean weight be approximately?
84 to 96
86 to 94
80 to 100
70 to 110
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.66
Suppose 30% of the women in a class received an A on the test and 25% of the men received an A. The class is 60% women. Given that a person chosen at random received an A, what is the probability this person is a women? Give answer round to two decimal places.
0.64
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
Sarah and Bob draw 13 cards each from a standard deck of 52.

A: Sarah has exactly two aces, what is the probability that Bob has exactly one ace?

B: Bob has exactly one ace.

Choose the correct option(s).

P(B | A) = 2*C(37,12)/C(39,13)
P(B) can not be calculated.
All options are correct.
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
A total of 500 married couples are polled about their salaries with the following results

[MSQ]

P( husband earns less than $25K) = 0.49
P( wife makes > $25K | husband makes > $25K ) = 0.31
P( wife makes > $25K | husband makes < $25K ) = 0.145
All options are correct.
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
An urn has 5 blue balls and 8 red balls. Each ball that is selected is returned to the urn along with an additional ball of the same color. Suppose that 3 balls are drawn in this way.

Choose the correct option(s).

P( all three balls are blue) = 0.077
P( all three balls are blue) = 0.023
P(Only 1 ball is blue) = 0.395
P(Only 1 ball is blue) = 0.493
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00

Color blindness is a sex-linked condition, and 5% of men and 0.25% of women are color blind. The population of the United States is 51% female. What is the probability that a color-blind American is a man? (Round of upto two decimals)

0.95
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00
A blood test indicates the presence of Amyotrophic lateral sclerosis (ALS) 95% of the time when ALS is actually present. The same test indicates the presence of ALS 0.5% of the time when the disease is not actually present. One percent of the population actually has ALS. Calculate the probability that a person actually has ALS given that the test indicates the presence of ALS. (Round off upto 2 decimals)
0.65
Difficulty Level: 1
Positive Marks: 2.00
Negative Marks: 0.00