Research Test Bank Chapter 16: Data Analysis Descriptive and Inferential Statistics

Standard Deviation

(Most freq used) Average deviation of scores from mean the larger is is, the more variability you have

What are examples of Bivariate Analysis?

(purpose: to compare differences or test relationships between the dependent variable) - t-test - chisquare - correlations

Normal Distribution

(theoretical concept) interval or ratio data group themselves about a midpoint in a distribution closely approximating the normal curve

What 6 considerations do the task of Interpretation have?

- credibility (results) - precision (estimate of effects) - Magnitude (effects and importance) - Meaning (of results) - Generalizability (results) - Implications (of the results for practice, theory, policy, further research. Interpreting research results involves making a series of inferences. We infer from study results to "truth in the real world.")

what are exampls Univariate Analysis?

- frequencies - means - standard deviations (when reporting demographic information about the sample - ie. % of males versus % of females)

What is the probability of making a type 1 error?

0.05 (called a false positive) (The researcher is willing to accept the fact that if the study was done 100 times, the decision to reject the null hypothesis would be wrong 5% of the time.) (Can also select 0.01 meaning 1% meaning 1 out of 100 trials.)

The nurse researcher opts to group frequency data using large interval widths in a research study. Which problem may be encountered by using this type of interval widths? a. Overlap can occur. b. Patterns can be obscured. c. Means cannot be determined. d. Some data may not fit into any category.

ANS: B

The nurse researcher opts to use interval-level data. The researcher's primary concern will be what? a. Categories must be mutually exclusive. b. Intervals between data categories must be equal. c. The rank of zero (0) represents the absence of the measured variable. d. Variance between assigned categories is qualitative rather than quantitative.

ANS: B

Which term represents the most frequent score in a frequency distribution? a. Mean b. Mode c. Median d. Percentile

ANS: B

The nurse researcher finds that the data include a score reported to be in the 75th percentile. The researcher interprets this to mean what? a. The score is at the median. b. The score has exceeded the mode. c. The score is exceeded by only 25% of the cases. d. The score represents the average of all scores measured at this time.

ANS: C

The nurse researcher is interested in using nominal level data. The object or event that could be used if nominal-level data are of primary interest is what? a. Test scores b. Education level c. Marital status d. Weight

ANS: C

The nurse researcher opts to use a measure of variability. Which measure of variability does the researcher recognize as being most unstable? a. Mean b. Median c. Range d. Semiquartile range

ANS: C

The nurse researcher opts to use ratio-level data. The researcher's primary concern will be what? a. Categories must be mutually exclusive. b. Intervals between data categories must be equal. c. The rank of zero (0) represents the absence of the measured variable. d. Variance between assigned categories is qualitative rather than quantitative.

ANS: C

​In a study of nurses' willingness to care for patients with a contagious disease, it was found that the greater the nurses' spirituality, the greater the willingness to provide care. This finding represents what? a. No correlation b. Perfect correlation c. Positive correlation d. Negative correlation

ANS: C

Which statements regarding measures of central tendency are accurate? (Select all that apply.) a. This classification of levels of measurement is scientifically inaccurate. b. Having the mean, mode, and median exactly the same indicates the measures have been correctly applied. c. They have great flexibility with regard to the amount of mathematical manipulation possible. d. They vary from sample to sample,even when the same trait or characteristic is measured.

ANS: C, D

​Which characteristic is an essential criterion for categorizing an object, event, or fact as nominal level data? (Select all that apply.) a. The degree of the characteristic must be positively related to the number assigned. b. Rank orders must be calculated for meaningful interpretation. c. Categories must be mutually exclusive. d. Category ranges cannot overlap

ANS: C, D

A nurse researcher would opt to use measures of central tendency in which case? a. When there is a need to describe how reliably the findings can be generalized b. When there is a need to describe how much dispersion is in the sample c. When there is a need to describe the accuracy of predictions made d. When there is a need to describe the average member of the sample

ANS: D

The alpha level that is interpreted by the nurse researcher as a highly statistically significant result is what? a. p = 0.20 b. p = 0.02 c. p = 0.002 d. p = 0.0002

ANS: D

The nurse researcher is interested in describing the assignment of numbers to objects or events. This is best achieved in which way? a. Through use of prediction b. Through use of dispersion c. Through use of variability d. Through use of measurement

ANS: D

The nurse researcher is interested in having the greatest flexibility possible in choosing statistical procedures. The level of measurement used to achieve this is what? a. Nominal b. Ordinal c. Interval d. Ratio

ANS: D

The nurse researcher should report the mean, mode, and median of a variable in a research study in which case? a. When the distribution is uneven. b. When the distribution is wide. c. When the distribution is narrow. d. When the distribution is symmetrical.

ANS: D

​The nurse researcher is using respiratory rate as a variable in a research study. The level of measurement most appropriate in this case is what? a. Nominal b. Ordinal c. Interval d. Ratio

ANS: D

What is the most unstable measure of variability?

RANGE

Assign the corrent definitions with the correct Level of Measurement: ____________ equal distances between score units; there is a rational, meaningful zero) ________________ ranking objects based on their relative standing on an attribute _____________________assigning numbers to classify characteristics into categories ______________________ objects ordered on a scale that has equal distances between points on the scale

Ratio, Ordinal, Nominal, Interva

Causation Warning

be careful - esp. when the study is nonexperimental and cross sectional

Type 2 Error

accept the null hypothesis when it is false

_____________ groups are sometimes created to investigate the frequencies of certain data

cohort

Multiple regression: LINeAR

continuous (interval or ratio level) dependent variable

True or False The statistical results of a study, in and of themselves, communicate great meaning.

false (The statistical results of a study, in and of themselves, do not communicate much meaning. Statistical results must be interpreted to be of use to clinicians and other researchers.)

platykurtosis

flatter than normal

If the results are credible and of sufficient precision and importance, then__________must be made about what they mean.

inferences

Precision and Magnitude -Results should be interpreted in:

light of the precision of the estimates (often communicated through confidence intervals) and magnitude of effects (effect sizes). considered especially important to clinical decision-making

Central Tendency

mean, median, mode (summarizes the middle of the group.) (Each measure has specific uses and is most appropriate to select types of distribution and measurement)

The larger the standard deviation, the ________________variability you have in your sample

more

___________ : used to determine what variables contribute to change in the dependent variable and to what degree

multiple regression

Skewness

not all data follow a normal cure - positive skew = low range of mean - negative = high range of mean

Operational definition of a variabe

provides a tool for quantification and measurement of a variable

Confidence Intervals

provides measure of certainty about findings (95% is most common, meaning over time, 95% of the time, the findings will fall within the range of values given as the C1.)

Type 1 Error

reject the null hypothesis when it is actually true

Variability or Dispersion

relates to spread of data - enables you to evaluate homogeneity or heterogeneity

what does the findings often indicate?

results, conclusions, interpretations, recommendations, generalizations, and implications for future research

Which measure of variability is the most frequenctly used?

standard deviation

Conceptual Definition of a variable

theoretical meaning of a value (grades, etc)

Multivariate analysis

to compare differences or test erlationships between dependent variable while controlling for confounding variables (Linear/logistic regression)

Interpreting research results involves making a series of inferences. We infer from study results to find the "__________________________"

truth in real world

Odds ratio

used in harm studies to estimate if a subject has been harmed by being exposed to a particular event (divide the odds in the treatment or exposed group by the odds of the control group_) (Those who drink coffee after 6:00 pm are 15x more likely to have poor sleep quality than those who abstain from coffee after 6:00 pm. ex. OR = 15.02; 95%; C1= 13-16))

A ___________ confidence interval often means poor sampling methods; the sample is not representative

wide

Kurtosis

A measure of if the data are peaked or flat relative to a normal distribution

Frequency Distribution

A summary chart, showing how frequently each of the various scores in a set of data occurs

The nurse researcher is interested in estimating how reliably data can be used to generalize the findings of a study. In order for this to occur, the researcher should use what? a. Inferential statistics b. Descriptive statistics c. Nonparametric statistics d. Mathematical statistics

ANS: A

The nurse researcher is using a nursing degree as a variable in a research study. The level of measurement most appropriate in this case is what? a. Nominal b. Ordinal c. Interval d. Ratio

ANS: A

The nurse researcher is using a research study that involved categories of patient weights. The level of measurement that would be most appropriate in this study is what? a. Nominal b. Ordinal c. Interval d. Ratio

ANS: A

The nurse researcher's data contain extremes of high and low scores. The measure of central tendency that should be used in order to be least affected by extremes of high and low scores is what? a. Mean b. Mode c. Median d. Percentile

ANS: A

Which data measurement scales typically use nonparametric tests of significance? (Select all that apply.) a. Nominal b. Ordinal c. Interval d. Ratio

ANS: A, B

Which measures of central tendency allow for relative rankings? (Select all that apply.)a. Mode b. Range c. Median d. Mean e. Semiquartile range f. Percentile g. SD

ANS: A, C

Which measures of central tendency allow for rank ordering with equal intervals? (Select all that apply.) a. Mode b. Range c. Mediand. Mean e. Semiquartile range f. Percentile g. SD

ANS: A, C, D

A nurse researcher determines the assignment of a number to an object for measurement by verifying what? a. The objects vary within a narrow range to meet category requirements. b. All objects assigned a specific measurement number are similar to all other objects assigned the same number. c. The objects assigned to one specific number are positively related to the dependent variable of the study. d. The objects assigned to one specific number are positivelyrelated to the independent variable of the study.

ANS: B

A nurse researcher would opt to use factor analysis in which case? a. To control statistically for a variable and measure differences among group means b. To take a large number of variables and group them into a smaller number of factors c. To test the relationship between two variables measured at interval or ratio level data d. To measure the relationship between one outcome or dependent variable and several dependent variables

ANS: B

The nurse researcher is interested in describing and summarizing the characteristics of the sample used in the research study. In order for this to occur, the researcher should use what? a. Inferential statistics b. Descriptive statistics c. Nonparametric statistics d. Mathematical statistics

ANS: B

The nurse researcher is using the percentage of nurses holding various nursing degrees as a variable in a research study. Which type of statistics is most appropriate in this case? a. Inferential statistics b. Descriptive statistics c. Nonparametric statistics d. Mathematical statistics

ANS: B

Multiple regression

a statistical technique that computes the relationship between a predictor variable and a criterion variable, controlling for other predictor variables - one dependent variable - multiple independent variables

What is Probability?

An event's long-run relative frequency in repeated trials under similar conditions (a number that decribes how likely the event will occur in similar conditions)

Are the results of each hypothesis included? Are the results concise and sequentially presented? Are the tests used for analysis presented? Are the results objectively presented? Do the tables and figures enhance the text? Are the results interpreted in the context of the hypotheses, framework, and process? If data are supported, is there a discussion of how the theoretical framework is supported? If data are not supported, is there a discussion of the study's weaknesses and strengths? Is the study's clinical relevance discussed? Are generalizations within the scope of the findings? Are recommendations made? What is the study's strength of evidence? these are all part of what process?

Critiquing

What does the result section have?

Data-bound section Both descriptive and inferential statistical results of testing are reported Exact tests, specific test value, and probability level achieved are reported All data presented whether supported or not supported

True or false Interpreting non-significant results, serendipitous significant results, and mixed results is very easy

False (Greatest challenges relate to to interpreting non-significant results, serendipitous significant results, mixed results)

Screening and cleaning of the data set include what tasks?

To treat missing data Determine outliers Detect data entry errors Determine normality/linearity

Multiple regression: LOGISTIC

dichotomous dependent variable

Leptokurtosis

steeper than normal