Psyc 10 Laboratory Assignment 2: Central Tendency & Variability(Be sure to put your names at the top of your syntax prior to saving as a PDF)

SPSS Application #1

A psychologist administered a stress inventory to 25 students at a freshman orientation session and obtained the following scores:

49 14 35 47 38 24 46 27 41 32 44 15 36 37 22 38 48 31 42 34 26 17 38 49 12 Enter this data in SPSS. Name the variable "stress" and give it a label.

Lab2Data Google Sheet- use this data to copy and paste into SPSS

Using SPSS calculate the mode, median, mean, variance, and standard deviation and report them below:

Mode = __________

Median = __________ Variance = __________

Mean = __________ Std Deviation = __________

Then, using the definitional formulas described in the text, determine the variance, and the standard deviationby handon a separate sheet of paper (attach the sheet to this lab) and report them below. Use the mean you calculated in SPSS in your variance calculation, do not calculate the mean by hand.

Variance = __________

Std Deviation = __________

Compare the results you obtain in SPSS to those you obtained by hand. Is there a difference? If there is a difference, why? If not, why not? Are the results you obtained in SPSS smaller, larger, or the same as those calculated by hand? Why?

Psyc10 1 Lab Assign 2

Names & Group # ___________________________________

Psyc 10 Laboratory Assignment 2: Central Tendency & Variability(Be sure to put your names at the top of your syntax prior to saving as a PDF)

SPSS Application #2

A psychologist administered a self-esteem inventory to 22 students in a statistics class and obtained the following scores (yes, this is the same data as App #1):

15 29 26 23 24 21 16 23 20 23 24 18 20 22 23 17 28 19 21 20 28 25 Enter this data in SPSS. Name the variable "slfesteem" and give it a label.

Using SPSS calculate the mode, median, mean, variance, and standard deviation and report them below:

Mode = __________

Median = __________ Variance = __________

Mean = __________ Std Deviation = __________

Then, using the definitional formulas described in the text, determine the variance, and the standard deviationby handon a separate sheet of paper (attach the sheet to this lab) and report them below. Use the mean you calculated in SPSS in your variance calculation, do not calculate the mean by hand.

Variance = __________

Std Deviation = __________

Compare the results you obtain in SPSS to those you obtained by hand. Is there a difference? If there is a difference, why? If not, why not? Are the results you obtained in SPSS smaller, larger, or the same as those calculated by hand? Why?

****** pls use this formula from our textbook****

****to calculate by hand

The mean is the most commonly used measure of central tendency of a distribution of scores.

The mean is the ordinary averagethe sum of the scores divided by the number of scores. In symbols, M = (X)/N. Other, less commonly used ways of describing the central tendency of a distribution of scores are the mode (the most common single value) and the median (the value of the middle score when all the scores are lined up from lowest to highest).

The variability of a group of scores can be described by the variance and the standard deviation. The variance is the average of the squared deviation of each score from the mean. In symbols, SD2=[(XM)2]/N The sum of squared deviations, (XM)2 , is also symbolized as SS. Thus SD2= SS/N . The standard deviation is the square root of the variance. In symbols, SD=SD2 . It is approximately the average amount that scores differ from the mean. There have always been a few psychologists who have warned against statistical methodology because in the process of creating averages, knowledge about the individual case is lost. Means and standard deviations are often given in research articles in the text or in tables.