Comp Prac - Point Estimates & Parameters

Question 1

Point Estimate (p with a hat)
A sample of the population

Parameter (the hat-less p)
The true and entire population

Sample size (n)

Bias = under or over estimate of the true population value

Question 2

In an experiment, subjects are considered independent if they are not aware of which group (control vs. treatment) they are assigned to.

Answer 2

False

Question 3

Bias: a systematic tendency to over- or under-estimate the true population value.

Answer 3

True

Question 4

All else being equal, the success-failure condition is more likely to be satisfied when the sample size is large (rather than small).

Answer 4

True

Question 5

Observations from a simple random sample can be considered independent.

Answer 5

True

Question 6

In a poll of 1000 UK residents, 78% described themselves as being in good health; 78% represents a population parameter.

Answer 6

False

Question 7

The term ‘standard error’ denotes systematic tendency (bias) in estimating the true population value.

Answer 7

False

Question 8

The standard deviation of a sampling distribution decreases as the sample size increases.

Answer 8

True

Question 9

Central Limit Theorem: when observations are independent and the sample size is sufficiently small, the sample proportion p^ will be equal to the corresponding parameter of interest.

Answer 9

False

Question 10

In a poll of 1000 UK residents, 78% described themselves as being in good health; 78% represents a population parameter.

Answer 10

False

Question 11

A sampling distribution represents the distribution of a point estimate based on samples of fixed size from a certain population.

Answer 11

True

Question 12

In the 2011 UK census, 81% of residents described themselves as being in good health; 81% represents a point estimate.

Answer 12

False

Question 13

Observations from a simple random sample can be considered independent.

Answer 13

True

Question 14

Sampling error: a systematic tendency to over- or under-estimate the true population value.

Answer 14

False

Question 15

Bias: a systematic tendency to over- or under-estimate the true population value.

Answer 15

True

Question 16

The standard error of a sampling distribution decreases as the sample size increases.

Answer 16

True

Question 17

A sampling distribution represents the distribution of a parameter based on samples of different size.

Answer 17

False

Question 18

The standard error of a sampling distribution increases as the sample size increases.

Answer 18

False

Question 19

All else being equal, the success-failure condition is more likely to be satisfied when the sample size is large (rather than small).

Answer 19

True

Question 20

The standard deviation of a sampling distribution decreases as the sample size increases.

Answer 20

True

Question 21

The term ‘standard error’ denotes the standard deviation of a sampling distribution.

Answer 21

True

Question 22

Observations from a simple random sample can be considered independent.

Answer 22

True

Question 23

Bias: how much an estimate will tend to vary from one sample to the next.

Answer 23

False

Question 24

The standard deviation of a sampling distribution increases as the sample size increases.

Answer 24

False

Question 25

The term ‘standard error’ denotes the standard deviation of a sampling distribution.

Answer 25

True

Question 26

In an experiment, subjects are considered independent if they undergo random assignment to the treatment groups.

Answer 26

True

Question 27

All else being equal, the success-failure condition is more likely to be satisfied when the sample size is large (rather than small).

Answer 27

True

Question 28

The term ‘standard error’ denotes the standard deviation of a sampling distribution.

Answer 28

True

Question 29

Central Limit Theorem: when observations are independent and the sample size is sufficiently large, the sample proportion p^ will tend to follow a normal distribution.

Answer 29

True

Question 30

Observations from a simple random sample cannot be independent.

Answer 30

False

Question 31

In the 2011 UK census, 81% of residents described themselves as being in good health; 81% represents a point estimate.

Answer 31

False

Question 32

An observation equal to the mean is always at the 50th percentile.

Answer 32

True

Question 33

The absolute value of an observation’s Z-score quantifies how unusual the observation is.

Answer 33

True

Question 34

The probability of a random observation falling within 2 standard deviations of the mean is roughly 95%.

Answer 34

True

Question 35

The probability of a random observation falling within 1 standard deviations of the mean is roughly 68%

Answer 35

True

Question 36

Sampling error: how much an estimate will tend to vary from one sample to the next.
True
Bias: how much an estimate will tend to vary from one sample to the next.
False
In the 2011 UK census, 81% of residents described themselves as being in good health; 81% represents a point estimate.
False
In a poll of 1000 UK residents, 78% described themselves as being in good health; 78% represents a point estimate.
True
The standard error of a sampling distribution increases as the sample size increases.
False