Stats 1-4

If you were to graph the following data, which of the following series of labels would produce a graph that best represents the data? Hours Studied Exam Score 1 70 2 79 3 86 5 98

1, 2, 3, 4, 5 on the X axis; 70, 80, 90, 100 on the Y axis

If we perform a square transformation on the numbers 3, 6, 9, 12, and 15, we get

9, 36, 81, 144, and 225

An instructor investigates whether the end of the chapter questions aid test performance by randomly assigning participants to one of two groups. One group completes half the questions, and another completes all the questions. Performance on a test is measured. The instructor should ask the question:

Are there consistent changes in test performance as a function of number of questions answered?

Statistics are represented by _____, and parameters are represented by _____.

English letters; Greek letters

Which of the following statements is inferential?

If recycling efforts continue as they have, energy costs will drop by 16%.

Quantitative variables measure _____ and qualitative variables measure _____.

amount; classification

If your final answer should contain two decimal places, then in the intermediate steps you should

carry at least three decimal places.

Suppose you are interested in how participants perform under different temperature conditions. You randomly select 30 participants and randomly assign them to work in one of three rooms. The rooms differ only with respect to temperature. You instruct all participants to solve the same jigsaw puzzle, and then you measure how long it takes each one to finish. In this research, temperature serves as the

condition.

Participants' income, categorized as "below poverty level" or "above poverty level," would be considered a(n)

continuous variable.

Empirical research involves measurement. Such measurement results in numbers or scores. These scores usually are referred to as

data.

A researcher investigates whether there is a relationship between gender and color discrimination by randomly selecting 50 males and 50 females and asking them to discriminate between colors. The variable measuring accuracy in color discrimination is a

dependent variable.

Descriptive statistics are always applied to

dependent variables.

The _____ is (are) the overall variable(s) the researcher is investigating, whereas the _____ is (are) the specific category(ies) under which the participant is tested.

independent variable; conditions of an independent variable

The term _____ refers to the fact that no two individuals are identical.

individual differences

In order to make statements about the population from information obtained from a sample, we must use

inferential statistics.

Which measurement scale shows how one individual is qualitatively different from another?

nominal.

A decimal number between 0 and 1 that indicates a fraction of the total is called a

proportion.

Technically, behavior-influencing variables that an experimenter cannot change by doing something to participants are called a(n)

quasi-independent variable.

Although researchers discuss the population of individuals, in statistics we sometimes talk of the population of

scores.

We study laws of nature by studying the relationship between our

scores.

Suppose you randomly select 40 participants, measure the length of each one's index finger, and also administer an IQ test to each. In this, you are investigating whether

there is a relationship between length of index finger and IQ score.

A researcher investigates whether there is a relationship between hours spent watching television and children's vocabulary by asking 40 randomly selected 11-year-olds how many hours of television they watch per week and then having them take a vocabulary test. What is the independent variable in this study?

there is no independent variable; the study is correlational

In behavioral science research, statistics is used

to answer research questions.

A researcher investigates whether there is a relationship between type of background music being listened to and responses to a mood inventory by having 60 randomly selected participants complete the mood inventory, with 20 randomly assigned to each of three rooms. In one room classical music is played in the background, in another hard rock music, and in a third country music. The type of background music variable is a(n)

true independent variable.