Question 1

The standard normal distribution has a mean of zero and variance of one.

Accepted Answer

A) True 
 B)False

Question 2

When mating two heterozygotes for alleles in which one is dominant to the other, if the usual Mendelian segregation process is occurring, the ratio of the offspring phenotypes produced should be 3:1. The dominant phenotype would be more common than the recessive one. Imagine a situation in which two heterozygotes are mated and among their 200 offspring, 165 show the dominant phenotype while 35 show the recessive phenotype. What is the conclusion of a two-sided binomial test using the normal distribution to approximate the binomial?

Accepted Answer

A)  Fail to reject null hypothesis, we lack evidence that anything other than usual Mendelian segregation is occurring. 
B)  Fail to reject null hypothesis, we have evidence that something other than usual Mendelian segregation is occurring. 
C)  Reject null hypothesis, we lack evidence that anything other than usual Mendelian segregation is occurring. 
D)  Reject null hypothesis, we have evidence that something other than usual Mendelian segregation is occurring. 
A)  Fail to reject null hypothesis, we lack evidence that anything other than usual Mendelian segregation is occurring. 
B)  Fail to reject null hypothesis, we have evidence that something other than usual Mendelian segregation is occurring. 
C)  Reject null hypothesis, we lack evidence that anything other than usual Mendelian segregation is occurring. 
D)  Reject null hypothesis, we have evidence that something other than usual Mendelian segregation is occurring.

Question 3

The term for the observation that the medical conditions of patients often improve when they are given inactive chemical substances is called which of the following?

Accepted Answer

A)  Confidence-based improvement 
B)  Dose response improvement 
C)  Placebo effect 
D)  Positive feedback 
A)  Confidence-based improvement 
B)  Dose response improvement 
C)  Placebo effect 
D)  Positive feedback

Question 4

To calculate probabilities using the normal probability distribution, we look at the area under the curve between the values we are interested in.

Accepted Answer

A) True 
 B)False

Question 5

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are between 58 and 65?

Accepted Answer

A)  502 
B)  509 
C)  519 
D)  529 
A)  502 
B)  509 
C)  519 
D)  529

Question 6

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are greater than 54?

Accepted Answer

A)  1,140 
B)  1,150 
C)  1,160 
D)  1,170 
A)  1,140 
B)  1,150 
C)  1,160 
D)  1,170

Question 7

When mating two heterozygotes for alleles in which one is dominant to the other, if the usual Mendelian segregation process is occurring, the ratio of the offspring phenotypes produced should be 3:1. The dominant phenotype would be more common than the recessive one. Imagine a situation in which two heterozygotes are mated and among their 200 offspring, 165 show the dominant phenotype while 35 show the recessive phenotype. What is the P-value of a two-sided binomial test using the normal distribution to approximate the binomial?

Accepted Answer

A)  0.018 
B)  0.036 
C)  0.054 
D)  0.072 
A)  0.018 
B)  0.036 
C)  0.054 
D)  0.072

Question 8

The Declaration of Helsinki states that when testing a new treatment, control patients _______.

Accepted Answer

A)  must be compensated financially to prevent abuse. 
B)  should receive an inactive yet safe chemical. 
C)  should receive no chemicals or drugs at all. 
D)  should receive the best current treatment. 
A)  must be compensated financially to prevent abuse. 
B)  should receive an inactive yet safe chemical. 
C)  should receive no chemicals or drugs at all. 
D)  should receive the best current treatment.

Question 9

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. What value below is closest to the value larger than exactly 55% of the population?

Accepted Answer

A)  90.6 
B)  90.8 
C)  91.0 
D)  91.2 
A)  90.6 
B)  90.8 
C)  91.0 
D)  91.2

Question 10

Crossbill finches have beaks that overlap with the top beak to one side or the other of the lower beak. Most populations have 50:50 ratios of "right-handed" and "left-handed" beaks, and the handedness of the beaks is thought to be randomly determined, so we expect to see equal numbers of right-beak and left-beak finches. Consider a survey of 140 crossbill finches, which reveals 84 with right beaks and 56 with left beaks. What is the conclusion of a two-sided binomial test using the normal distribution to approximate the binomial?

Accepted Answer

A)  Fail to reject null hypothesis, we lack evidence that the handedness of the beaks is non-random. 
B)  Fail to reject null hypothesis, we have evidence that the handedness of the beaks is non-random. 
C)  Reject null hypothesis, we lack evidence that the handedness of the beaks is non-random. 
D)  Reject null hypothesis, we have evidence that the handedness of the beaks is non-random. 
A)  Fail to reject null hypothesis, we lack evidence that the handedness of the beaks is non-random. 
B)  Fail to reject null hypothesis, we have evidence that the handedness of the beaks is non-random. 
C)  Reject null hypothesis, we lack evidence that the handedness of the beaks is non-random. 
D)  Reject null hypothesis, we have evidence that the handedness of the beaks is non-random.

Question 11

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are less than 62?

Accepted Answer

A)  599 
B)  898 
C)  1,103 
D)  1,314 
A)  599 
B)  898 
C)  1,103 
D)  1,314

Question 12

Carlos says that he thinks that while humans are more right-handed than left-handed, the same probably isn't true for gorillas. Luis disagrees and says they probably are asymmetric too, but maybe they're more left-handed. Imagine they collect handedness data for 60 gorillas based on videos of the gorillas eating and 37 of the gorillas appear to be right-handed. Use the normal distribution to approximate the binomial distribution to answer this question. Does the data support Carlos or Luis? As part of your answer, present the test statistic and the P-value it corresponds to.

Accepted Answer

To determine whether the data supports C

Question 13

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. The 75th percentile most closely corresponds to which value of Z?

Accepted Answer

A)  65.0 
B)  65.2 
C)  65.4 
D)  65.6 
A)  65.0 
B)  65.2 
C)  65.4 
D)  65.6

Question 14

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. What proportion of values are larger than 78?

Accepted Answer

A)  0.0228 
B)  0.8666 
C)  0.9772 
D)  0.9975 
A)  0.0228 
B)  0.8666 
C)  0.9772 
D)  0.9975

Question 15

Which equation shown is correct for a normal distribution with a median of 25 and a standard deviation of 5?

Accepted Answer

A)  $f(x)=\frac{1}{\sqrt{10 \pi}} e^{\frac{-(x-25)^{2}}{25}}$ 
B)  $f(x)=\frac{1}{\sqrt{25 \pi}} e^{\frac{-(x-25)^{2}}{25}}$ 
C)  $f(x)=\frac{1}{\sqrt{50 \pi}} e^{\frac{-(x-25)^{2}}{50}}$ 
D)  $f(x)=\frac{1}{\sqrt{100 \pi}} e^{\frac{-(x-100)^{2}}{50}}$ 
A)  $f(x)=\frac{1}{\sqrt{10 \pi}} e^{\frac{-(x-25)^{2}}{25}}$ 
B)  $f(x)=\frac{1}{\sqrt{25 \pi}} e^{\frac{-(x-25)^{2}}{25}}$ 
C)  $f(x)=\frac{1}{\sqrt{50 \pi}} e^{\frac{-(x-25)^{2}}{50}}$ 
D)  $f(x)=\frac{1}{\sqrt{100 \pi}} e^{\frac{-(x-100)^{2}}{50}}$

Question 16

Using the normal approximation to the binomial distribution is most accurate when the proportion is closest to 0.5.

Accepted Answer

A) True 
 B)False

Question 17

The equation for a normal distribution with a mean of 30 and a variance of 20 is
 $f(x)=\frac{1}{\sqrt{40 \pi}} e^{\frac{-(x-30)^{2}}{40}}$

Accepted Answer

A) True 
 B)False

Question 18

Crossbill finches have beaks that overlap with the top beak to one side or the other of the lower beak. Most populations have 50:50 ratios of "right-handed" and "left-handed" beaks, and the handedness of the beaks is thought to be randomly determined, so we expect to see equal numbers of right-beak and left-beak finches. Consider a survey of 140 crossbill finches, which reveals 82 with right beaks and 58 with left beaks. What is the P-value of a two-sided binomial test using the normal distribution to approximate the binomial?

Accepted Answer

A)  0.026 
B)  0.052 
C)  0.078 
D)  0.104 
A)  0.026 
B)  0.052 
C)  0.078 
D)  0.104

Question 19

Imagine that your friend comes down with a cold and after being sick for a few days takes a supplement called "essence of wormroot" and gets better soon afterward. She then credits the supplement for her recovery. Based on what you know about the likely mechanism of how placebos work, what is the likely explanation for her recovery?

Accepted Answer

The likely explanation for her recovery

Question 20

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. Which value below is closest to the IQR?

Accepted Answer

A)  8.1 
B)  8.3 
C)  8.5 
D)  8.7 
A)  8.1 
B)  8.3 
C)  8.5 
D)  8.7

The standard normal distribution has a mean of zero and variance of one.

The term for the observation that the medical conditions of patients often improve when they are given inactive chemical substances is called which of the following?

To calculate probabilities using the normal probability distribution, we look at the area under the curve between the values we are interested in.

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are between 58 and 65?

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are greater than 54?

The Declaration of Helsinki states that when testing a new treatment, control patients _______.

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. What value below is closest to the value larger than exactly 55% of the population?

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are less than 62?

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. The 75th percentile most closely corresponds to which value of Z?

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. What proportion of values are larger than 78?

Which equation shown is correct for a normal distribution with a median of 25 and a standard deviation of 5?

Using the normal approximation to the binomial distribution is most accurate when the proportion is closest to 0.5.

The equation for a normal distribution with a mean of 30 and a variance of 20 is $f(x)=\frac{1}{\sqrt{40 \pi}} e^{\frac{-(x-30)^{2}}{40}}$

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. Which value below is closest to the IQR?

Statistics and Samples

Displaying Data

Describing Data

Estimating With Uncertainty

Probability

Hypothesis Testing

Analyzing Proportions

Fitting Probability Models to Frequency Data

Contingency Analysis: Associations Between

Inference for a Normal Population

Comparing Two Means

Handling Violations of Assumptions

Designing Experiments

Comparing Means of More Than Two Groups

Correlation Between Numerical Variables

Regression

Multiple Explanatory Variables

Computer-Intensive Methods

Likelihood

Meta-Analysis: Combining Information From

Filters

Exam 10: The Normal Distribution

The standard normal distribution has a mean of zero and variance of one.

The term for the observation that the medical conditions of patients often improve when they are given inactive chemical substances is called which of the following?

To calculate probabilities using the normal probability distribution, we look at the area under the curve between the values we are interested in.

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are between 58 and 65?

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are greater than 54?

The Declaration of Helsinki states that when testing a new treatment, control patients _______.

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. What value below is closest to the value larger than exactly 55% of the population?

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. To the closest integer, how many values in the population are less than 62?

Imagine a population consisting of 1,500 values that are normally distributed around a mean of 60, which exhibits a standard deviation of 8. The 75th percentile most closely corresponds to which value of Z?

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. What proportion of values are larger than 78?

Which equation shown is correct for a normal distribution with a median of 25 and a standard deviation of 5?

Using the normal approximation to the binomial distribution is most accurate when the proportion is closest to 0.5.

The equation for a normal distribution with a mean of 30 and a variance of 20 is f(x)=140πe−(x−30)240f(x)=\frac{1}{\sqrt{40 \pi}} e^{\frac{-(x-30)^{2}}{40}}f(x)=40π​1​e40−(x−30)2​

Consider a population of 900 values that are normally distributed with a mean of 90 and standard deviation of 6. Which value below is closest to the IQR?

Statistics and Samples

Displaying Data

Describing Data

Estimating With Uncertainty

Probability

Hypothesis Testing

Analyzing Proportions

Fitting Probability Models to Frequency Data

Contingency Analysis: Associations Between

Inference for a Normal Population

Comparing Two Means

Handling Violations of Assumptions

Designing Experiments

Comparing Means of More Than Two Groups

Correlation Between Numerical Variables

Regression

Multiple Explanatory Variables

Computer-Intensive Methods

Likelihood

Meta-Analysis: Combining Information From

Filters

The equation for a normal distribution with a mean of 30 and a variance of 20 is $f(x)=\frac{1}{\sqrt{40 \pi}} e^{\frac{-(x-30)^{2}}{40}}$