Problem Set 2: Research Scenario:  The Davidson Trauma Scale (DTS) (Davidson, 1997) is a self-report instrument that indicates the presence and severity of trauma symptoms. It is often used to detect PTSD, with scores ranging from 0 to 136, and a mean in the general population of 11 (Davidson et al., 2002). A clinical psychologist is interested in measuring trauma in a sample of paramedics at the hospital where she works. Using the data in the table below, set up your data file in SPSS and conduct a one-sample t test to determine whether this sample scores higher than general population on the DTS. Create a histogram to display the distribution of the sample’s DTS scores. DTS Scores 23 69 45 13 19 57 78 59 68 83 32 41 12 19 27 10   what is the SPSS output of the t test ?

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...