Chapters 1 & 2
Identify the sample being studied... The number of hours a group of 12 children in Mrs. Smith's kindergarten class sleep in a day.
12 children selected
parameter
a numerical description of a population characteristic -usually unobservable (mean, median, standard deviation)
population
a particular group of interest -whole group -group we want to know about -characteristics are called parameters -parameters are usually unknown and fixed
meta-analysis
a study that compiles information from multiple previous studies
census
a study where data is obtained from every member of the population
sample
a subset of the population from which data are collected -part of the group -group we do know about -characteristics are called statistics -statistics are always known -statistics change with the sample
placebo
a substance that appears identical to the actual treatment but contains no intrinsic beneficial elements
Classify the following scenario as a meta-analysis or a case study... Your uncle checks the tires on his car every five days for signs of uneven wear and proper inflation.
case study
Select each member of the entire population. Simple Random Sampling Stratified Sampling Cluster Sampling Systematic Sampling Stratified Sampling Census
census
A market researcher interviews each member from each of the ten randomly chosen neighborhoods throughout a city. Simple Random Sampling Stratified Sampling Cluster Sampling Systematic Sampling Stratified Sampling Census
cluster sampling
When researchers assign participants to different groups, they are trying to control for _____________, which may affect the result of an experiment. response variables cross-sectional variables confounding variables longitudinal variables
cofounding variables
informed consent
completely disclosing to participants the goals and procedures involved in a study and obtaining their agreements to participate
In order to simplify data collection, a biologist hand-selects the first ten members to arrive to be studied in depth... Simple Random Sampling Stratified Sampling Cluster Sampling Systematic Sampling Stratified Sampling Census
convenience sampling
quantitative data
counts or measurements -numerical data ex: age, pulse, height
cross-sectional study
data is collected at a single point in time
case-control study
data is collected on past "exposures" from 2 groups: 1. cases who are known to have the disease of interest 2. controls who are similar but don't have the diseases
longitudal study
data is gathered by following a particular group over a period of time
A(n) ___________ is a subject who strays from the directions they were given for the study, yet they remain in the sample. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherents
nonadherents
If a respondent omits one or more questions when answering a survey, this is known as _______________. researcher bias response bias sampling bias nonresponse bias participation bias
nonresponse bias
sample statistics
numerical descriptions of sample characteristics
researcher bias
occurs when a researcher influences the results of a study
response bias
occurs when a researcher's behavior causes a participant to alter his or her response or when a participant gives an inaccurate response
sampling bias
occurs when the sample chosen does not accurately represent the population being studied
nonresponse bias
occurs when there is a lack of participation in a self-selected sample from certain segments of a population, when a person refuses to participate in a survey, or when a respondent omits questions when answering a survey
participation bias
occurs when there is a problem with the participation—or lack thereof—of those chosen for the study.
ordinal data
ordered categories ex: year in school (freshman, sophomore, junior, senior)
Places earned in various events by members of a track team at a meet Interval Ordinal Ratio Nominal
ordinal
dropouts
participants who begin a study but fail to complete it
nonadherents
participants who remain in the study until the end but stray from the directions they were given
When many participants in a study have strong opinions, _____________ could occur. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherents
participation bias
participants
people being studied in an experiment
subjects
people or things being studied in an experiment
Researchers are investigating a drug to help reduce gastrointestinal issues in individuals with a gluten sensitivity. There is a group that is given pills to take they are told will help, but the pills do not contain the drug. It is found that this group has seen an improvement with their symptoms. What could be causing this? placebo effect double-blind experiment single-blind experiment treatment group
placebo effect
The annual salaries of all the parents of your classmates population or sample?
population
Determine if the numerical value describes a population parameter or a sample statistic... The average price of a car at the new car dealership in town is $34,100
population parameter
Errors that appear when data are entered inattentively are examples of ___________. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherent(s)
processing errors
nominal data
qualitative data consisting of labels or names -categorical, names things
Classify the following data. Indicate whether the data is qualitative or quantitative, indicate whether the data is discrete, continuous, or neither, and indicate the level of measurement for the data... The lifetimes of 100 five volt batteries is recorded. qualitative or quantitative? discrete, continuous, or neither? nominal, ordinal, interval, or ratio?
quantitative continuous ratio
interval data
quantitative data that can be arranged in a meaningful order -doesn't have natural zero on scale
ratio data
quantitative data that can be ordered, zero point indicates absence of something
continuous data
quantitative data that can take on any value in a given interval and are usually measurements -uses decimal places ex: height
discrete data
quantitative data that can take on only particular values and are usually counts -has gaps ex: heart rate, shoe size
If a researcher influences the results of the study to favor a certain outcome, this is called. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherents
researcher bias
If a participant in a study does not give the correct answer to a question, this is known as ___________. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherent(s)
response bias
The final exam scores of 5 out of the 22 students in your chemistry class. population or sample?
sample
convenience sampling
sample is chosen because it is convenient for the researcher to select
Determine if the numerical value describes a parameter or a statistic... A recent poll of 533 students showed that the average number of hours they study per week is 6.8
sample statistic
If a study of all college students at a particular college resulted in only freshmen being sampled, this would be considered _________________. researcher bias response bias sampling bias nonresponse bias participation bias
sampling bias
treatment
some condition that is applied to a group of subjects in an experiment
A scientist chooses five students at random from each class... Simple Random Sampling Stratified Sampling Cluster Sampling Systematic Sampling Stratified Sampling Census
stratified sampling
single-blind experiment
subject do not know if they are in the control group or treatment group, but the people interacting with the subjects in the experiment know in which each group each subject has been placed
After a crime researcher has enumerated a sampling frame, he picks a random starting point and chooses every fiftieth member. Simple Random Sampling Stratified Sampling Cluster Sampling Systematic Sampling Stratified Sampling Census
systematic sampling
data
the counts, measurements, or observations gathered about a specific variable in a population in order to study it
statistics
the science of gathering, describing, and analyzing data OR the actual numerical descriptions of sample data
inferential statistics
uses descriptive statistics to estimate population parameters
variable
value/characteristic that changes among members of the population
explanatory variable
variable that causes the change in the response variable
response variable
variable that responds to the treatment
representative sample
has the same relevant characteristics as teh population and does not favor one group from the population over another
Classify the following data. Indicate whether the data is qualitative or quantitative, indicate whether the data is discrete, continuous, or neither, and indicate the level of measurement for the data... There are 5000 participants in a 10km run. Twenty participants are taken at random and their final standing in the race is recorded. qualitative or quantitative? discrete, continuous, or neither? nominal, ordinal, interval, or ratio?
Qualitative Neither Ordinal
Identify the population being studied... The overall exam scores of 10 out of the 40 students in your economics class.
All students in your economic class
If an outcome is favored over another, we call this _________. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherents
Bias
Indicate the level of measurement for the data set described... High temperatures (in degrees Fahrenheit) across the country for one day in July Ratio Interval Nominal Ordinal
Interval
Determine whether an observational or experimental study is appropriate to address the following statement.... A car wash operator wants to find out the average age of his clientele.
Observational
Identify the population being studied and the sample chosen... The number of times 15 out of 30 students on your floor order take-out in a week.
Population: The 30 students on your floor Sample: The 15 students selected on your floor
stratified sampling
a few members from each group are randomly chosen
institutional review board (IRB)
a group of people who review the design of a study to make sure that it is appropriate and that no unnecessary harm will come to the subject involved
control group
a group of subjects to which no treatment is applied in an experiment
treatment group
a group of subjects to which researchers apply a treatment in an experiment
cluster sampling
all members from a few random chosen groups are selected
Determine whether the statement describes a descriptive or inferential statistic... 59% of all students at the local university eat out more than twice a week.
descriptive statistic
In a ___________ experiment, neither examiners nor participants know whether the participant will receive a placebo.
double-blind experiment
If too many participants decide to _______________ of an experiment, then the sample may no longer represent the population. Bias Participation Bias Researcher Bias Processing Error(s) Dropout Nonadherent(s)
dropout
observational study
either observes data that already exists or observes what is naturally occurring with the subjects -researchers do not manipulate or assign conditions to the subjects
processing errors
errors that occur because of the date being processed, such as typos when data are being entered -can be fixed!
random sampling
every member of the population has an equal chance of being selected
systematic sampling
every nth member of the population is chosen
simple random sampling
every sample of the population has an equal chance of being selected
cofounding/lurking variables
factors other than the treatment that cause an effect on the subjects of an experiment
bias
favoring of a certain outcome in a study
descriptive statistics
gathers, sorts, summarizes and displays data -basically the summaries of the sample
experiment
generated data to help identify cause and effect relationships -the researchers assign conditions to the test subjects
biased
if not representative, the sample is said to be biased
Determine whether the statement describes a descriptive or inferential statistic A survey of 1478 people revealed that 52% eat while they drive; therefore it can be assumed that 52% of the U.S. population eats while they drive.
inferential statistic ??
____________________ is meant to ensure that participants understand the procedures of a study and any possible harm that might happen to them. Double-blind experiment Single-blind experiment Informed consent Case study Meta-analysis
informed consent
To perform a research study, you need to obtain approval from an ______________.
institutional review board
Indicate the level of measurement for the data set described... Release years of a list of 100 of the greatest rock albums of all time Ratio Interval Nominal Ordinal
interval
Determine if the numerical value describes a parameter or a statistic... A recent poll of 1373 corporate executives showed that the average price of their cars is $32,200.
it only refers to part of the group so it is a sample statistic
qualitative data
labels or descriptions of traits -categorical data ex: health rating, gender, exercise staus
case study
looks at multiple variables that affect a single event
double-blind experiment
neither the subjects nor the people interacting with the subjects know to which group each subject belongs
Religious preference specified from a survey (Christian, Hindu, Jewish, etc.) Interval Ordinal Ratio Nominal
nominal