chapter 3

If a portion of people from a population are asked to complete an assessment, then the average score among that group of people would be considered a... A) sample mean B) population mean C) median split D) modal mean

A. Sample mean

A researcher measures the mean time (in seconds) it takes two groups of children to complete an activity task. She finds that Group A (M = 22 seconds) completed the task more quickly than Group B (M = 36 seconds). She then computes a weighted mean for both groups combined and calculates = 26. Based on the information provided, which group had a larger sample size? A) Group A B) Group B C) The sample size is equal in both groups. D) It is not possible to know this without knowing the sample size for each group

A. group A

Which type of mean is used to describe a portion of individuals in a given population? A) sample mean B) population mean C) restricted mean D) none of the above.

A. sample mean

A researcher records the following data for the number of different food items chosen by seven participants in a buffet-style setting: 1, 6, 2, 5, 4, 3, and 7. Is the mean equal to the median in this example? A) Yes. B) No; the median is larger than the mean. C) No; the mean is larger than the median. D) There is not enough information to answer this question.

A. yes

A researcher records the following data for the number of dreams recalled during a night of sleep for 10 college students: 3, 2, 4, 4, 3, 1, 1, 0, 2, and 0. Is the mean equal to the median in this example? A) Yes. B) No; the median is larger than the mean. C) No; the mean is larger than the median. D) There is not enough information to answer this question.

A. yes

What terms refer to each of the following measures, respectively: mean, median, and mode. A) middle, most, and average B) average, middle, and most C) average, most, and middle D) most, average, and middle

B. average, middle, most

The distribution of personal income for U.S. citizens is positively skewed. If the median annual income is $44,000, this implies that the mean annual income is... A) smaller B) larger C) the same D) There is not enough information to answer this question

B. larger

The ________ is the sum of all scores (in a sample or population) divided by the number of scores summed. A) mode B) median C) mean D) range.

C. mean

A professor grades 120 research papers and reports that the average score was an 80%. What do we know about the sum of the differences of these 120 scores from their mean of 80%? A) The sum of the differences is minimal. B) The sum of the differences is 80%, the same as the mean. C) The sum of the differences is equal to zero. D) It is impossible to know without knowing each of the 120 scores.

C. the sum of the differences is equal to zero

A researcher selects a sample of 6 males and 11 females. She asks participants to rate the likelihood they would do female-stereotyped jobs (such as nursing or school teaching) on a scale from 1 = not likely at all to 5 = very likely. Men indicated that they would be less likely to do these jobs (M = 2.1) compared with women (M = 4.3). What is the weighted mean for this entire sample of 17 participants? A) 2.1 B) 4.3 C) 3.2 D) 3.5

D. 3.5

The mean is an appropriate measure of central tendency for... A) data that are normally distributed B) data that are on an interval or ratio scale C) data in which the mean, median, and mode are equal D) all of the above

D. all of the above

A researcher reports, "the average patron (n = 22) in a local bar consumed more than twice the number of drinks (per day) on weekends (M = 5.4 drinks) compared to weekdays (M = 2.3 drinks)." Although not stated directly, how do we know that the patrons in this study constitute a sample, and not a population of patrons at this local bar? A) We can't know for sure because this was not stated directly. B) The notation for a sample mean was used. C) The notation for sample size was used. D) both B and C

D. both B and C