Chp. 1 STATS

ratio scale

measurements that have a true zero and are distributed in equal units

data

(plural) a set of scores, measurements, or observations that are typically numeric

datum

(singular) a single measurement or observation, usually referred to as a score or raw score

A population can be ______ group of interest to a researcher. Question options: A. any B. only one C. only a small D. only a large

A

______ is the variable in an experiment that is manipulated between conditions being observed. Question options: A. Independent variable B. Quasi-independent variable C. Dependent variable

A

State the four scales of measurement in order from least informative to most informative. Question options: A. ordinal, nominal, interval, ratio B. nominal, ordinal, interval, ratio C. nominal, ordinal, ratio, interval D. ordinal, nominal, ratio, interval

B

Which of the following best describes a dependent variable? Question options: A. the sample variable B. the measured behavior C. the manipulated variable D. the population variable

B

__________ describe(s) characteristics in a population, whereas ____: A. Statistics; parameters B. Parameters; statistics C. Descriptive; inferential D. Inferential; descriptive

B

Σ x^2 +47 instructs you to... A. square each score and add 47 to it, then sum those numbers B. square each score, add up the squared scores, then add 47 to that sum C. add 47 to each score, square the result, and sum of those numbers D. add up the scores, square that sum, and add 47 to it

B

A psychologist wants to study a small population of 40 students in a local private school. If the researcher was interested in selecting the entire population of students for this study, then how many students must the psychologist include? A. None, because it is not possible to study an entire population in this case. B. At least half, because this would constitute the majority of the population. C. All 40 students, because all students constitute the population

C

A study assesses the optimal size (number of other members) for study groups. The variable "Size of group" is.... A. discrete and interval B. continuous and ordinal C. discrete and ratio D. continuous and interval

C

Statistical analysis allows researchers to ______. Question options: A. collect data B. claim that an observation is scientific C. evaluate scientific observations D. study physical phenomena but not behavior

C

A researcher is interested in the effect of amount of sleep on high school students exam scores. A group of 75 high school boys agree to participate in the study. The boys are.... A. a statistic B. a variable C. a parameter D. a sample

D

Descriptive statistics are procedures used to ______. Question options: A. summarize a set of scores or observations B. organize a set of scores or observations C. make sense of a set of scores or observations D. all of these

D

Researchers observed that students exam scores were higher the more sleep they had the night before. This study is... A. descriptive B. experimental comparison of groups C. non-experimental group comparison D. correlational

D

Three research methods common to research in the behavioral sciences are ______. Question options: A. experimental, transferable, and correlation B. experimental, variable, and correlational C. experimental, operational, and quasi-correlational D. experimental, quasi-experimental, and correlational

D

What are two characteristics of rating scales that allow researchers to use these values on an interval scale of measurement? Question options: A. Values on an interval scale have a true zero but are not equidistant. B. Values on an interval scale have differences and a true zero. C. Values on an interval scale are equidistant and have a true zero. D. Values on an interval scale are assumed to be equidistant but do not have a true zero.

D

All research methods can show cause-and-effect relationships. T/F

False

All research methods have an independent variable. T/F

False

Qualitative variables can be continuous or discrete. Question options: 1) False 2) True

False

Σ x^2= (Σx)^2 T/F

False

Quantitative Research

Research that provides data that can be expressed with numbers, such as ranks or scales.

(Σx) * (Σx)= (Σx)^2 T/F

True

A ratio scale variable can be continuous or discrete. Question options: 1) True 2) False

True

An experiment is the only method that can demonstrate cause-and-effect relationships between variables. Question options: 1) True 2) False

True

Inferential statistics are used to help the researcher infer the unknown parameters in a given population Question options: 1) True 2) False

True

Most research studies use data from samples. T/F

True

statistics

a branch of mathematics used to summarize, analyze, and interpret a group of numbers or observations.

population parameter

a characteristic (usually numeric, such as the mean or variance) that describes a population. The population characteristic typically of greatest interest to a researcher is the mean score.

sample statistic

a characteristic (usually numeric, such as the mean or variance) that describes a sample.

operational definition

a description of some observable event in terms of the specific process or manner by which it was observed or measured.

quasi-independent variable

a preexisting variable that is often a characteristic inherent to an individual, which differentiates the groups or conditions being compared in a research study.

random assignment

a random procedure used to ensure that participants in a study have an equal chance of being assigned to a particular group or condition.

correlational studies

a research method that examines how variables are naturally related in the real world, without any attempt by the researcher to alter them or assign causation between them

sample

a set of individuals, items, or data selected from a population of interest.

equidistant scale

a set of numbers distributed in equal units.

research method

a set of systematic techniques used to acquire, modify, and integrate knowledge concerning observable and measurable phenomena; also called scientific method.

quasi-experiment

a type of research design where a comparison is made, as in an experiment, but no random assignment of participants to groups occurs

continuous variable

a variable measured along a continuum at any place beyond the decimal point. A continuous variable can thus be measured in fractional units

A study that examines the relation between amount of studying and exam score. The number of hours students study for an exam and exam score are measured, then the relationship is observed. Is it an experiment, quasi-experiment, or correlational study?

correlational

A study that examines the effects of sugar consumption on attention. One group receives a sugary snack and the other group receives a non-sugary snack before class, then attention is measured for both groups. Is it an experiment, quasi-experiment, or correlational study?

experiment

scales of measurement

identify how the properties of numbers can change with different uses. Four scales of measurement are nominal, ordinal, interval, and ratio.

discrete variable

measured in whole units or categories that are not distributed along a continuum.

nominal scale

measurements in which a number is assigned to represent something or someone. Nominal variables are typically categorical variables that have been coded. (used to categorize or classify individuals)

interval scale

measurements that have no true zero and are distributed in equal units. Examples include scores, temperature, latitude, and longitude.

ordinal scale

measurements where values convey order or rank alone.

inferential statistics

procedures used that allow researchers to infer or generalize observations made with samples to the larger population from which they were selected. Examples include z tests, t tests, and F tests.

descriptive statistics

procedures used to summarize, organize, and make sense of a set of scores called data. Descriptive statistics are typically presented graphically, in tabular form (in tables), or as summary statistics (single values).

A study examines the effect of parenting style on engagement in juvenile delinquency by comparing youth delinquency rates across the three groups/kinds of parenting styles. Is it an experiment, quasi-experiment, or correlational study?

quasi-experiment

levels of the independent variable

specific conditions of the independent variable; also called the levels of the factor for groups in quasiexperiments and correlational research designs.

Coding

the procedure of converting a nominal or categorical variable to a numeric value

science

the study of phenomena, such as behavior, through strict observation, evaluation, interpretation, and theoretical explanation.

experiment

the use of methods and procedures to make observations in which the researcher fully controls the conditions and experiences of participants by applying three required elements of control (manipulation, randomization, and comparison/control) to isolate cause-and-effect relationships between variables

true zero

the value 0 truly indicates nothing or the absence of the phenomena being measured on a scale of measurement.

independent variable (IV).

the variable that is manipulated in an experiment. This variable remains unchanged (or "independent") between conditions being observed in an experiment. It is the "presumed cause," so to speak.

dependent variable (DV)

the variable that is measured in each group of a study and is believed to change in the presence of the independent variable. It is the "presumed effect," so to speak.

qualitative variable

varies by class. This is often represented as a label and describes nonnumeric aspects of phenomena.