Author Question: A researcher is attempting to decide whether to hire a statistician to assist with the statistical ... (Read 47 times)

darbym82 · **on:** Jul 8, 2018

A researcher is attempting to decide whether to hire a statistician to assist with the statistical aspects of the study. If the researcher cannot perform which of the following for a quantitative study, a statistician should be contacted?

(Select all that apply.)
a. Provide sample demographics using descriptive statistics.
b. Perform reliability testing of the study instruments.
c. Design and perform analyses to answer research questions and test hypotheses.
d. Design and perform an exploratory analysis of the data.
e. Hand-compute all statistical calculations.
f. Prepare the data for analysis.
g. Perform a power analysis.
h. Interpret the results obtained by all statistical computations.

Question 2

A measured value is within two standard deviations of the mean but not within one standard deviation, and it is greater than the mean. The distribution is very close to a normal distribution. What does this signify? (Select all that apply.)

a. This particular value is not an outlier.
b. In the data set, almost 2/3 of the values are closer to the mean than this one is.
c. The data point falls within the majority of the measured values, in terms of its closeness to the mean.
d. In the data set, at least 4 of the values are further from the mean than this particular value is.
e. In this data set, between 65 and 95 of the values are smaller in value than this one is.

catron30 · **Reply #1 on:** Jul 8, 2018

Answer to Question 1

ANS: A, B, C, D, F, G, H
To perform statistical analysis of data from a quantitative study, one must be able to (1) determine the necessary sample size to adequately power your study, (2) prepare the data for analysis, (3) describe the sample, (4) test the reliability of measures used in the study, (5) perform exploratory analyses of the data, (6) perform analyses guided by the study objectives, questions, or hypotheses, and (7) interpret the results of statistical procedures. If the researcher is not able to do all of these, a statistician is consulted. Descriptions of the sample demographics are made statistically.

Answer to Question 2

ANS: A, B, D, E
The range, standard deviation, and variance are statistics that describe the extent to which the values in the sample vary from one another. The most common of these statistics to be reported in the literature is the standard deviation, because of its direct association with the normal curve. If the frequency distribution of any given variable is approximately normal, knowing the standard deviation of that variable allows the reader to know what percentages of subjects' values on that variable fall between +1 and 1 standard deviation. In a normal distribution, when a standard deviation is calculated, 34.13 of the values are between the mean score and 1 standard deviation above the mean. Similarly, 34.13 of the values are between the mean score and 1 standard deviation below the mean. The middle 95.44 of the subjects' scores are between +2 standard deviations and 2 standard deviations.