Question 1

Random samples provide ________ estimates of population averages if the samples have small ________.

Accepted Answer

Random samples provide good estimates of population averages if the samples have small standard deviations, because smaller standard deviations indicate that the sample data points are closer to the mean, thus more accurately reflecting the population average.

Question 2

The average price for different brands of toothpaste could be visually displayed in a(n)

Accepted Answer

A bar graph is the best choice for visually displaying the average price for different brands of toothpaste because it allows for easy comparison of the prices between the different brands. A normal curve would not be appropriate as it is typically used to display data that follows a specific distribution, such as a bell curve. Extrapolation and standard deviation are statistical concepts that are not necessary for displaying this type of data.

Question 3

Mrs.Smith is measuring the height of all the children in her class and notices that the scores form a symmetrical,bell-shaped distribution.This is also known as the

Accepted Answer

A symmetrical, bell-shaped distribution is characteristic of a normal curve.

Question 4

When an arithmetic average is reported in the news,it is most important for readers to

Accepted Answer

It is important to consider whether the arithmetic average is distorted by a few extreme cases because outliers can significantly skew the average and paint an inaccurate picture of the data.

Question 5

A lopsided distribution of scores in which the mean is much larger than both the mode and median is said to be

Accepted Answer

A lopsided distribution of scores in which the mean is much larger than both the mode and median is said to be skewed. This is because the distribution is not symmetrical around the mean and is skewed towards the larger values. Option A is incorrect because statistical significance refers to the likelihood of the results occurring by chance. Option B is incorrect because extrapolation is the process of estimating values beyond the observed range of data. Option C is incorrect because standard deviation is a measure of the spread of data around the mean.

Question 6

Which measure of central tendency is used to calculate the average of your school grades?

Accepted Answer

The mean is used to calculate the average of a set of grades by summing all the grades and dividing by the number of grades.

Question 7

The most frequently occurring score in a distribution of scores is the

Accepted Answer

The most frequently occurring score is known as the mode.

Question 8

Seven members of a Girl Scout troop report the following individual earnings from their sale of candy: $4,$1,$7,$6,$8,$2,and $7.In this distribution of individual earnings

Accepted Answer

The answer of Seven members of a Girl Scout troop...

Question 9

When you read a bar graph,it is most important for you to

Accepted Answer

When reading a bar graph, it is important to note the range and size of the scale values in order to accurately interpret and understand the data being presented. This includes paying attention to the intervals on the scale and ensuring they are consistent throughout the graph. While identifying the correct measure of central tendency can also be important, it is not as crucial as understanding the scale values. Transforming the data into a normal curve and identifying the standard deviation are not necessary when reading a bar graph.

Question 10

The mean of a distribution of scores is the

Accepted Answer

The mean of a distribution is the arithmetic average of all the scores.

Question 11

The maximum height of a normal curve corresponds to the ________ of a normal distribution.

Accepted Answer

The maximum height of a normal curve corresponds to the mean of a normal distribution. This is because the mean is the central value around which the distribution is symmetrically centered. The range and standard deviation do not have a direct relationship with the maximum height of a normal curve, and statistical significance is a measure of how likely it is that a result has occurred by chance, which is not directly related to the shape of the distribution.

Question 12

The median of a distribution of scores is the

Accepted Answer

The median is the middle score in a distribution of scores, meaning half of the scores are above it and half are below it. It is not related to the most frequent score (mode), the range of scores, or the arithmetic average (mean).

Question 13

Central tendency is to variation as ________ is to ________.

Accepted Answer

Central tendency measures, such as mean and median, provide information about the center or typical value of a distribution, while measures of variation, such as standard deviation, provide information about the spread or dispersion of the distribution. Therefore, mean (or median) is to central tendency as standard deviation is to variation.

Question 14

When Mr.Adams calculated his students' algebra test scores,he noticed that two students had extremely low scores.Which measure of central tendency is affected most by the scores of these two students?

Accepted Answer

The mean is the average of all the scores and is heavily affected by extreme scores, which in this case are the extremely low scores of the two students. The median isn't affected because it only takes the middle value, while the mode represents the most common score and isn't affected by two low scores. The standard deviation measures how much the scores vary from the mean, but it's not the most affected measure of central tendency in this case. Therefore, the best choice is A) mean.

Question 15

Median is to range as central tendency is to ________.

Accepted Answer

Range and variation both deal with the spread of data, while median and central tendency both deal with representing the typical value within a dataset. Therefore, the appropriate analogy would be between range and variation, and between median and central tendency.

Question 16

For which of the following distributions of scores would the median most clearly be a more appropriate measure of central tendency than the mean?

Accepted Answer

The answer of For which of the following distributions of...

Question 17

In a group of five individuals,two report annual incomes of $10,000,and the other three report incomes of $14,000,$15,000,and $31,000,respectively.The mode of this group's distribution of annual incomes is

Accepted Answer

The mode is the value that appears most frequently in a data set. In this case, $10,000 is reported twice, more than any other value, making it the mode.

Question 18

Seven members of a boys' club reported the following individual earnings from their sale of cookies: $2,$9,$8,$10,$4,$9,and $7.In this distribution of individual earnings

Accepted Answer

To find the median, we need to first arrange the values in order: $2,$4,$7,$8,$9,$9,$10. The median is the middle value, which is $8$.
To find the mean, we can add up all the values and divide by the number of values: 
$(2+4+7+8+9+9+10)/7 = 7.14$
To find the mode, we look for the value that appears most frequently. In this case, there are two modes: $9$ appears twice. 
Therefore, the median is greater than the mean ($8 > 7.14$) and less than the mode ($9$). So the best choice is C.

Question 19

One person in a 10-person group is 10 times older than anyone else in the group.With respect to age,it is most likely that the majority of group members are younger than the group's

Accepted Answer

Given one person is significantly older, this outlier increases the mean age more than the median or mode, making the majority younger than the mean.

Question 20

Differences between two samples are LEAST likely to be statistically significant if the samples are _______ and the standard deviations of the samples are _______.

Accepted Answer

When the samples are small, the differences between the samples are less likely to be statistically significant as the sample size is small. When the standard deviations of the samples are large, it means that the data is spread out and more dispersed, making the differences between the samples more likely to be statistically significant. Therefore, when the samples are small and the standard deviations of the samples are large, the differences between the samples are most likely to be statistically significant. The other options (A, B, D) do not fit this pattern.

Quiz 3: Research Strategies: How Psychologists Ask and Answer Questions

Random samples provide estimates of population averages if the samples have small .