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The benefit to using a sample that utilizes narrow sampling criteria is that there is increased a. control of extraneous variables. b. generalizability. c. heterogenicity. d. range of values and scores.

ANS: A A sample that is narrowly defined is more homogeneous and has greater control of extraneous variables. The narrower the sample, the less generalizable it is. A narrow sample is homogeneous, not heterogeneous. A narrow sample will have a smaller range of values and scores.

A researcher wishes to study the effects of a nursing intervention on children with cancer and obtains a sample of school-age children hospitalized for cancer treatment in a local hospital. This sample represents the a. accessible population. b. general population. c. target population. d. theoretical population.

ANS: A An accessible population is the portion of the target population to which the researcher has reasonable access. The sample is obtained from the accessible population. A general population is the population, not just those meeting eligibility criteria. The target population is the entire set of individuals who meet the sampling criteria. The theoretical population is the same as the target population, which is the entire set of individuals who meet the sampling criteria.

Which is a type of probability sampling? a. Cluster b. Convenience c. Network d. Quota

ANS: A Cluster sampling is a type of probability sampling. Convenience, network, and quota sampling are all types of nonprobability sampling.

When conducting a study in which it is not possible to determine the true number of subjects who meet eligibility criteria and obtaining a random sample would be time consuming and expensive, the researcher will use which sampling method? a. Cluster sampling b. Simple random sampling c. Stratified random sampling d. Systematic sampling

ANS: A Cluster sampling is often used when the researcher is unable to identify the individual elements making up the population and when obtaining a random sample is time consuming or expensive. Simple random sampling is the most basic random sampling technique and is usually used when the population is clearly identifiable. Stratified random sampling is used when the researcher knows some of the variables in the population that are critical for achieving representativeness. Systematic sampling is used when an ordered list of all members of the population is available and involves selecting every kth individual on the list.

Which of the following is true about convenience sampling? a. It tends to be less expensive and easier to conduct. b. It requires fewer subjects to achieve a representative sample. c. It is used more often in quantitative research. d. It allows the researcher greater control over extraneous variables.

ANS: A Convenience sampling is less expensive and a relatively easy method of obtaining subjects. The number of subjects needed is not determined by sampling technique but by the type of data collected. Convenience sampling is not used less often in qualitative research. Convenience sampling offers less control over extraneous variables.

A nurse conducts a study to examine the effects of a new intervention on FEV1 levels in patients with COPD and uses all patients admitted to a hospital during a 2-month period. This is an example of which type of sampling method? a. Convenience b. Network c. Quota d. Random

ANS: A In convenience sampling, the researcher uses subjects as they are available until the desired sample size is reached. Network sampling uses social networks to obtain subjects who might not be readily accessible otherwise. Quota sampling involves convenience sampling but adds techniques to ensure that certain subject types are represented. Random sampling attempts to ensure that all potential subjects have equal, random chances to participate.

A researcher plans to utilize a systematic random sampling method from a population of 5000 eligible subjects, using a sample of 200 subjects. Beginning at a randomly selected point on the list of subjects, what is the gap between elements? a. 25 b. 50 c. 100 d. 200

ANS: A In systematic sampling, the researcher selects every kth individual on a list, beginning at a randomly selected starting point. The population size is divided by the desired sample size to give the gap between elements. 5000/200 = 25. A gap of 50 between elements would be correct for a sample size of 100 subjects. A gap of 100 between elements would be correct for a sample size of 50 subjects. A gap of 200 between elements would be correct for a sample size of 25 subjects.

In a qualitative study, a sample may be too small if a. the depth of information is low. b. the effect size is too large. c. the saturation of information is high. d. the scope of the study is narrow.

ANS: A Information gained in a qualitative study must be in depth and of high quality to be meaningful. If the depth or quality is low, the sample size should be increased. The effect size is related to the effects of the independent variables on the dependent variables and is a measure of quantitative studies. When saturation of information levels is low, the sample size is too low. A narrow scope means that a smaller sample may be used.

Which is a type of nonprobability sampling? a. Purposeful b. Simple random c. Stratified random d. Systematic

ANS: A Purposeful sampling is a type of nonprobability sampling. Simple random, stratified random, and systematic sampling are all types of probability sampling.

The goal of appropriate sampling in research is to a. accurately reflect the characteristics of the target population. b. completely define the traits of the accessible population. c. identify all attributes of the sample population. d. study an entire population

ANS: A Sampling involves selecting a group of people, events, behaviors, or other elements with which to conduct a study. Samples are expected to represent a target population of subjects who meet eligibility criteria for inclusion in the study. The accessible population are those people who are available for participation in the study. The accessible population may not be representative of the target population. The aim of sampling is to represent the target population, not to merely identify characteristics of the sample population. The goal of sampling is to study a representative sample of the larger population on which conclusions about the larger population may be drawn.

A researcher conducting a qualitative study knows that saturation of information has occurred when a. additional sampling reveals redundant information. b. data collected confirms theoretical models. c. subjects participating are representative of the general population. d. the desired sample size has been reached

ANS: A Saturation of information occurs when additional sampling provides no new information, only redundancy of previously collected data. Verification of information occurs when theoretical models or hunches are confirmed. Stratified and quota sampling seek participants who are representative of the general population. Achieving the desired sample size helps to improve the power of the study and improve the significance of findings.

A pilot study reveals a wide variation in measurement values among subjects with an overall mean value that is higher than among the general population. By increasing the sample size in a subsequent study, the researcher expects to a. decrease the variation of scores among subjects. b. increase the variation of scores among subjects. c. decrease the mean value of scores among subjects. d. increase the mean value of scores among subjects.

ANS: A The random variation of scores is the expected difference in values that occurs when different subjects from the same sample are examined. As sample size is increased, this variation decreases. The systematic variation is related to selecting subjects whose measurement values differ from those of the population. Increasing the sample size has no effect on mean scores.

Which of the following are accurate statements about the research setting when conducting research? Select all that apply. a. Three common settings for conducting nursing studies are natural, partially controlled, and highly controlled. b. All studies are strengthened by having more than one setting, making the sample more representative of the accessible population. c. The selection of a setting in quantitative and qualitative research is based on the purpose of the study, accessibility of the setting or sites, and number and types of participants available in the setting. d. Laboratories are considered a highly controlled setting in which experimental studies often are conducted. e. Conducting a study in a natural setting means that the researcher manipulates or changes the environment for the study.

ANS: A, C, D The research setting is the site or location used to conduct a study. Three common settings for conducting nursing studies are natural, partially controlled, and highly controlled. The selection of a setting in quantitative and qualitative research is based on the purpose of the study, accessibility of the setting or sites, and number and types of participants available in the setting. The setting needs to be clearly described in the research report, with a rationale for selecting it. Laboratories, research or experimental centers, and test units in hospitals or other healthcare agencies are highly controlled settings in which experimental studies often are conducted. Some studies are strengthened by having more than one setting, making the sample more representative of the target population. Conducting a study in a natural setting means that the researcher does not manipulate or change the environment for the study.

Which of the following are true statements about representativeness of a sample in quantitative research? Select all that apply. a. In quantitative research, you need to evaluate representativeness in terms of the setting, characteristics of the subjects, and distribution of values on variables measured. b. Representativeness means that the sample, accessible population, and target population are different in as many ways as possible. c. The setting identified in a study does not influence the representativeness of the sample. d. Researchers who gather data from subjects across a variety of settings have a more representative sample of the target population than those limiting the study to a single setting. e. Studies that obtain data from large databases have less representative samples. f. A sample must be representative in terms of characteristics such as age, gender, ethnicity, income, and education, which often influence study variables.

ANS: A, D, F In quantitative research, you need to evaluate representativeness in terms of the setting, characteristics of the subjects, and distribution of values on variables measured. Researchers who gather data from subjects across a variety of settings have a more representative sample of the target population than those limiting the study to a single setting. A sample must be representative in terms of characteristics such as age, gender, ethnicity, income, and education, which often influence study variables. Representativeness means that the sample, accessible population, and target population are alike in as many ways as possible. The setting identified in a study does influence the representativeness of the sample. Studies that obtain data from large databases have more representative samples.

ANS: D A partially controlled setting is an environment that is manipulated or modified in some way by the researcher. A hospital unit allows researchers control over the environment in this way. A controlled setting is an artificially controlled environment that allows a high level of control by the researcher and usually involves research centers or laboratories. A natural, or field, setting occurs naturally, without control by the researcher.

ANS: B A research sleep lab is a special unit designed to conduct research or to collect data and allows the most control by the researcher. A nursing home unit and an intensive care unit allow for partial control. A school-based clinic allows for the least control.

Which type of research study tends to require a larger sample size than the others? a. Case study b. Descriptive study c. Experimental study d. Quasi-experimental study

ANS: B Descriptive studies often require very large samples. Multiple variables may be examined, and extraneous variables are likely to affect subject response(s) to the variables under study. Case studies are, by definition, composed of a very small sample, possibly even just one individual. Experimental studies often have fewer subjects than a descriptive or correlational study. Quasi-experimental studies often have fewer subjects than a descriptive or correlational study.

In a study of patients who have dementia, a researcher wishes to examine the effects of moderate exercise on patients' abilities to perform self-care. The researcher decides to use subjects between 70 and 80 years of age who have been diagnosed with dementia for less than 1 year. A patient who is 65 years old meets a. eligibility criteria. b. exclusion criteria. c. inclusion criteria. d. sampling criteria.

ANS: B Exclusion criteria are characteristics that the researcher does not want in the elements or subjects of the study. Inclusion criteria, eligibility criteria, and sampling criteria are those characteristics that the subject or element must possess to be part of the target population.

In qualitative research, the sampling plan is developed to a. decrease systematic bias. b. increase the representativeness of the findings related to the phenomena. c. minimize the need for discussion of cultural elements of the study. d. reduce sampling error.

ANS: B In qualitative research, a sampling plan is developed to increase representativeness of the findings related to the phenomenon, processes, or cultural elements being studied. Decreasing systematic bias and reducing sampling error are the goals of sampling in quantitative research. Decreasing systematic bias and reducing sampling error are the goals of sampling in quantitative research. The cultural elements of the study are unrelated to sample size.

Which of the following is true about sample size in a qualitative study? a. It is determined by the sensitivity of the measurement tools. b. It is considered adequate when the researcher detects no new knowledge. c. It is influenced by the expected effect size and the probability of a type II error. d. It is determined by the number of variables and data analysis techniques.

ANS: B In qualitative research, the researcher looks for data saturation, which is reached when no new information is being discovered from additional subjects. Quantitative research sample size is influenced by the sensitivity of the measurement tools, effect size, probability of a type II error, number of variables, and data analysis techniques.

The goal of sampling theory is to a. clearly define sample types used in research studies. b. determine the best way to achieve representative samples. c. develop methods for collecting data more efficiently. d. provide frameworks for data analysis.

ANS: B Sampling theory was developed to determine the best way to acquire a sample that accurately reflects the population under study. Part of sampling theory is defining sample types, but this is not the goal of sampling theory. Part of sampling theory is developing methods for collecting data, but this is not the goal of sampling theory. Sampling theory does not provide frameworks for data analysis

A researcher wishes to evaluate the management of chemotherapy side effects in children with acute lymphocytic leukemia (ALL). Children with ALL in this study are an example of which of the following? a. Accessible population b. Element of the population c. Sample population d. Target population

ANS: D The target population is the entire set of individuals who meet the sampling criteria. The accessible population is that portion of the entire population that the researcher can use. An element is an individual unit in a study. A sample is a subset of the population that represents that population.

A researcher enters a list of subjects from a sampling frame into a computer and the computer randomly assigns subjects to control or treatment groups. This is an example of a. cluster sampling. b. simple random sampling. c. stratified random sampling. d. systematic sampling.

ANS: B Simple random sampling is the most basic of the probability sampling plans and is achieved by randomly selecting elements from the sampling frame. It can be done by computer, as in this case. Cluster sampling occurs when the researcher selects subjects from groups of subjects within the larger population, as with groups from specific regions or cities. Stratified random sampling occurs by ensuring that the proportions of characteristics among the population are represented in both the control and experimental groups. Systematic sampling is used when an ordered list of all members of the population is available and involves selecting every kth individual on the list.

A researcher begins a study with 250 subjects, and 50 subjects drop out before the study is concluded. The researcher will declare 20% as the sample a. acceptance rate. b. attrition rate. c. refusal rate. d. retention rate.

ANS: B The sample attrition rate is the percentage of subjects who withdraw from a study after the study has begun. The acceptance rate is the percentage of subjects who meet eligibility requirements who consent to participate. The refusal rate is the percentage of subjects who meet eligibility requirements who refuse to participate. The retention rate is the percentage of subjects who remain in the study after the study has begun.

Which of these sampling techniques is least likely to produce findings that are generalizable to a larger population? a. Cluster b. Convenience c. Quota d. Systematic

ANS: B There is little opportunity to control for bias in a convenience sample. Cluster sampling is a type of random sampling and is much stronger than convenience sampling. Quota provides for a more representative sample than convenience sampling, so it is stronger. Systematic sampling is a type of random sampling and is much stronger than convenience sampling.

A researcher conducts a survey of patients seen in an inner-city ambulatory clinic to determine barriers to receiving health care. The target population includes African-American, Hispanic, and Somali immigrant patients, as well as a variety of foreign-born students from a nearby university. The researcher chooses subjects from the African-American, Hispanic, and Somali immigrant populations to participate. This is which type of sampling? a. Network b. Purposive c. Quota d. Theoretical

ANS: B With purposive sampling, the researcher consciously selects certain participants to include in the study and may or may not include all typical subject types. Network sampling takes advantage of social networks and the fact that friends tend to have characteristics in common. Quota sampling involves techniques to ensure that certain subject types are represented to improve the representativeness of the total population. Theoretical sampling is used in qualitative research to develop a selected theory and subjects are selected based on their ability to provide relevant, varied, and rich information for theory generation.

During a study about nurses' ability to teach lifestyle changes in patients with coronary artery disease, the researcher discovers that many nurses have negative attitudes about obesity. The researcher develops a survey to examine these attitudes. This is an example of a. grounded theory research. b. intraproject sampling. c. saturation of information. d. verification of information.

ANS: B Intraproject sampling is done during data collection and analysis when new information is needed to gain insight into a phenomenon or concept that arises during the study. Grounded theory research is concerned with development of theories. Saturation of information occurs when additional sampling provides no new information, only redundancy of previously collected data. Verification of information occurs when researchers are further able to confirm hunches or theories.

Which type of setting is most commonly used in qualitative research? a. Controlled b. Multiple c. Natural d. Partially controlled

ANS: C A natural, or field, setting is a real-life, uncontrolled environment and is often used for descriptive and correlational quantitative research and in qualitative studies. Controlled and partially controlled settings are more commonly used in quantitative research. Researchers may choose to conduct a study using multiple settings, but this is not as common as using natural settings in qualitative research

A researcher tests a measurement tool in a pilot study and notes a wide variance in scores. To improve the significance of the study's findings in subsequent studies, the researcher will a. apply quota sampling techniques. b. decrease the sample size. c. increase the sample size. d. use cluster sampling techniques.

ANS: C As variance in instrument scores increases, the sample size needed to obtain significance increases, so the researcher should increase the sample size in subsequent studies. Quota and cluster sampling techniques help to increase the representativeness of the sample but do not affect the significance of the measurement findings.

A researcher wishes to identify all school-age children who have type 2 diabetes mellitus in a local community to develop a sampling methodology for a study of this population. Which might serve as a barrier to obtaining this information? a. Affordable Care Act (ACA) b. Consolidated Omnibus Budget Reconciliation Act (COBRA) c. Health Insurance Portability and Accountability Act (HIPAA) d. Institutional Review Board (IRB)

ANS: C HIPAA contains guidelines about sharing patient information and may serve as a barrier to obtaining names of potential subjects. The ACA does not address the sharing of patient information. COBRA is concerned with healthcare coverage after termination of coverage. IRBs govern the use of human subjects in research.

A researcher will conduct a qualitative study about partners of patients diagnosed with sexually transmitted diseases. This researcher will use which sampling technique to achieve the best representation of this population? a. Accidental sampling b. Cluster sampling c. Network sampling d. Simple random sampling

ANS: C Network sampling is useful for locating samples that are difficult or impossible to obtain in other ways. Network sampling takes advantage of social networks and the fact that friends tend to have characteristics in common. Accidental or convenience sampling would not be likely to yield an adequate sample of individuals with sexually transmitted diseases. Cluster sampling would not be the best method for finding the desired sample in this case. Simple random sampling would not work well because the researcher is looking for a specific subgroup of the general population.

A researcher wishes to examine whether a teaching program for parents increases adherence to a drug regimen among children with seizure disorders. A convenience sample of children in a large teaching hospital is proposed. To prevent confounding of the results by socioeconomic status and type of health insurance, the researcher will utilize which additional sampling technique? a. Cluster b. Network c. Quota d. Theoretical

ANS: C Quota sampling involves convenience sampling but adds techniques to ensure that certain subject types are represented. Cluster sampling occurs when the researcher selects subjects from groups of subjects within the larger population, as with groups from specific regions or cities. Network sampling uses social networks to obtain subjects who might not be readily accessible otherwise. Theoretical sampling is used in qualitative research to develop a selected theory. Subjects are selected based on their ability to provide relevant, varied, and rich information for theory generation.

The type of nonprobability design that is most likely to yield a representative sample is a. convenience sampling. b. accidental sampling. c. quota sampling. d. network sampling.

ANS: C Quota sampling involves convenience sampling but adds techniques to ensure that certain subject types are represented. Convenience sampling, also called accidental sampling, is a relatively weak approach because it provides little opportunity to control for biases. Network sampling uses social networks to obtain subjects who might not be readily accessible otherwise.

To decrease the probability of systematic variation in a study to evaluate the effects of a teaching program on disease management, the researcher will use which sampling process? a. Cluster sampling b. Convenience sampling c. Random sampling d. Systematic sampling

ANS: C Random sampling decreases the probability of systematic bias. Cluster, convenience, and systematic sampling increase the risk that the sample population has attributes that differ from the general population.

A researcher begins with a registry of all patients with HIV in the United States. The researcher uses a computer to generate a random sample from the list, and then those individuals agree to participate in a study. What kind of sample has been created? a. Cluster b. Convenience c. Simple random d. Stratified random

ANS: C Simple random sampling is when every member of the population has an equal chance of selection for the sample. Cluster sampling occurs when a researcher develops a sampling frame that consists of a larger division than the one desired and it is chosen randomly; then subjects from the chosen subsets are selected randomly. A convenience sample is based on any member of the target population that is easily accessible to the researcher. In a stratified sample, knowledge about characteristics of the population is used to create a sample that is representative of the larger population.

In a study investigating type 2 diabetic patients' ability to make lifestyle changes, the researcher randomly selects a sample from a list of all patients diagnosed with type 2 diabetes in the United States. The researcher also selects the sample by randomly selecting patients diagnosed for 3 years or longer and those who are newly diagnosed. What sampling technique is used in this study? a. Cluster b. Quota c. Stratified random d. Systematic

ANS: C Stratified random sampling is used when certain characteristics of the group are identified and then proportionately included in the randomly chosen sample. In cluster sampling, a researcher develops a sampling frame that includes a list of all the possible elements of the identified population, and those are randomly selected. Then the sample is randomly selected from those groups. Quota sampling is a type of convenience sampling in which a predetermined number of subjects is drawn from groups within the population to ensure appropriate representation. Systematic sampling is selecting every kth individual from a listing of the population

A researcher who wishes to study the effects of a prenatal breastfeeding education program on the length of time African-American inner-city women breastfeed infants learns that 70% of women in the target population are unmarried. To achieve stratified random sampling in a sample of 50 subjects, the researcher will a. conduct the study using unmarried subjects only. b. randomly assign all subjects to control versus experimental groups. c. select a random sample of 35 unmarried and 15 married subjects. d. select 25 subjects who are married and 25 who are not married.

ANS: C Stratified random sampling is used when the researcher knows some of the variables in the population that are critical for achieving representativeness, such as marital status. In this case, subjects are randomly selected, but stratification by marital status to match the target population proportions helps to improve generalizability of the findings. Using only married subjects makes the results ungeneralizable to unmarried subjects. Randomly assigning subjects without stratification does not make the groups representative. Having equal numbers from each group is possible if subjects are randomly assigned and not selected.

Which statement is true about systematic sampling? a. A nonrandom starting point is used when selecting subjects. b. It can be used when the desired sample size is unknown. c. It provides a random chance for inclusion as a subject. d. Subjects have an equal chance for inclusion in the study.

ANS: C Systematic sampling provides a random but not equal chance for inclusion. A random starting point is used in this type of sampling. Systematic sampling is used when the desired sample size is known. Subjects do not have an equal chance for inclusion.

Which statement is true about effect size? a. There is one type of effect size measure used in research studies. b. The effect size is the extent to which the null or statistical hypothesis is true. c. The effect size is the extent to which the null or statistical hypothesis is false. d. When the effect size is small, detecting it is easier and can be done with a smaller sample.

ANS: C The effect size is the extent to which the null or statistical hypothesis is false. In other words, the strength of the expected relationship between two variables or differences between two groups. There are different types of effect size measures and each corresponds to the type of statistic computed. When the effect size is large, detecting it is easier and can be done with a smaller sample

Prior to initiating a research study, a researcher conducts a power analysis to determine the sample size necessary for a power level of 0.8 and an alpha of 0.05. The researcher will a. apply a quota sampling technique to improve generalizability. b. decrease the sample size to minimize costs. c. increase the sample size to avoid a type II error. d. use stratified random sampling to minimize error.

ANS: C The minimum acceptable level of power for a study is 0.8, which results in a 20% chance of a type II error. This study has a 40% chance of such an error and is unacceptable. To increase the power, the researcher should increase the sample size. Quota sampling and stratified random sampling do not necessarily affect a study's power.

A researcher wishes to conduct a survey of attitudes about illness among young adults with cystic fibrosis. The researcher contacts a nearby regional medical cystic fibrosis clinic, where 250 young adults who have cystic fibrosis are seen. A group of 50 young adults are selected to complete the survey. These 50 people are the a. accessible population. b. elements of the population. c. sample population. d. target population.

ANS: C A sample is that group of people who are representing the entire population and participating in the study. Samples are expected to represent an entire population. The accessible population is that portion of the entire population that the researcher can use; which, in this case, would be the 250 patients at this medical center. The target population is the entire set of individuals who meet the sampling criteria. An element is an individual unit of a study population.

A nurse researcher compares the outcomes of administration of a bronchodilator either via nebulizer or by metered-dose inhaler and collects data on subjects in a pediatric inpatient hospital unit. This is an example of which type of setting? a. Controlled b. Field c. Natural d. Partially controlled

ANS: D A partially controlled setting is an environment that is manipulated or modified in some way by the researcher. A hospital unit allows researchers control over the environment in this way. A controlled setting is an artificially controlled environment that allows a high level of control by the researcher and usually involves research centers or laboratories. A natural, or field, setting occurs naturally, without control by the researcher.

To decrease the time needed to achieve saturation in information in a qualitative study, the researcher will a. broaden the scope of the study. b. increase the number of theoretical concepts. c. keep definitions of concepts vague. d. narrow the study's scope.

ANS: D If a topic is difficult to define and has a broad scope, it will take more subjects to obtain quality data. To decrease the time needed for data collection, the researcher will narrow the scope of the study. Increasing the number of concepts, using vague definitions, and broadening the scope of the study will all result in increased time needed to collect data.

researcher uses a sample whose members have characteristics like those of the population from which it is drawn. This is an example of a a. cluster sample. b. purposive sample. c. random sample. d. representative sample.

ANS: D Representativeness means that the sample, accessible population, and target populations are alike in as many ways as possible. Knowing a sample as a cluster sample, purposive sample, or random sample tells how it was created but does not define a representative sample.

A researcher conducts a pilot study using a convenience sample of children with seizure disorders. A reviewer of this study's manuscript may conclude that the findings of this study a. are generalizable to most children with seizures. b. have little credibility; they are extremely biased. c. provide no useful information. d. should be replicated using a wider population.

ANS: D Representativeness of the sample is a concern in convenience sampling, and generalizability is therefore limited. In a convenience sample, representativeness of the sample is a concern, and generalizability is therefore limited. Not all studies with a convenience sample are more biased than studies with other sampling methods. Intervention studies with a convenience sample can certainly provide useful information, even though further testing might be needed to be able to apply the findings to a large population.

A researcher wishes to conduct a study to determine the effects of an intervention on high school students. In this study, high school students represent the a. accessible population. b. elements of the population. c. sample population. d. target population.

ANS: D The target population is the entire set of individuals who meet the sampling criteria. An accessible population is the portion of the target population to which the researcher has reasonable access. An element is an individual unit of a study population. A sample is that group of people who are representing the entire population and participating in the study. Samples are expected to represent an entire population.

During the data collection phase of a qualitative study, the researcher notes previously untheorized links among concepts. The researcher will continue to collect data until a. a quota of each subject type is achieved. b. saturation of information is noted. c. the desired sample size is attained. d. verification of information occurs.

ANS: D Verification of information occurs when theoretical models or hunches are confirmed. When new links are noted during the study, data collection should continue until verification of this information has occurred. Quota sampling seeks participants who are representative of the general population. Saturation of information occurs when additional sampling provides no new information, only redundancy of previously collected data. Achieving the desired sample size helps to improve the power of the study and improve the significance of findings.

When using stratified random sampling, the researcher can a. achieve greater control over subject selection. b. avoid discussion of the effects of extraneous variables. c. lower the costs associated with sampling. d. use a smaller sample size.

ANS: D With stratification, the researcher can use a smaller sample size and achieve the same degree of representativeness in relation to the stratified variable as a large sample acquired through simple random sampling. The researcher does not achieve greater control of subject selection, since random selection is still used. Discussion of extraneous variables should always occur, even with stratified random sampling techniques. There is no guarantee that costs will be less with this type of sampling technique.