Assignment #1 - PSYCHOLOGICAL STATISTICS

Assignment 1 Due Wednesday September 13 th , 2023 at 6:00pm - Please upload to WebCampus prior to class. Worth 30 points Q1 . (6 points) 75 72 66 72 75 46 55 98 43 78 63 96 73 71 86 92 52 56 85 100 84 90 79 56 For the exam scores listed above, use SPSS to create: A. Descriptive statistics table Descriptive Statistics N Minimum Maximum Mean Std. Deviation Exam Scores 24 43.00 100.00 73.4583 16.36268 Valid N (listwise) 24 B. A frequency distribution: Exam Scores Frequency Percent Valid Percent Cumulative Percent Vali d 43.00 1 4.2 4.2 4.2 46.00 1 4.2 4.2 8.3 52.00 1 4.2 4.2 12.5 55.00 1 4.2 4.2 16.7 56.00 2 8.3 8.3 25.0 63.00 1 4.2 4.2 29.2 66.00 1 4.2 4.2 33.3

71.00 1 4.2 4.2 37.5 72.00 2 8.3 8.3 45.8 73.00 1 4.2 4.2 50.0 75.00 2 8.3 8.3 58.3 78.00 1 4.2 4.2 62.5 79.00 1 4.2 4.2 66.7 84.00 1 4.2 4.2 70.8 85.00 1 4.2 4.2 75.0 86.00 1 4.2 4.2 79.2 90.00 1 4.2 4.2 83.3 92.00 1 4.2 4.2 87.5 96.00 1 4.2 4.2 91.7 98.00 1 4.2 4.2 95.8 100.0 0 1 4.2 4.2 100.0 Total 24 100.0 100.0 C. Histogram:

A. Mean: 104.9 B. Median: 105 C. Mode: 97, 105 Q3. (9 points total) Consider the following height (in inches) for five women: Height (Height - M) (Height - M) 2 65 1 1 71 7 49 63 -1 1 59 -5 25 62 -2 4 Sum = 320 0 80 Mean = 64 A. Fill in the table. B. What is the range of the heights? The range of the heights is 12. C. Calculate the standard deviation (imagine this is the entire population of women in a group). Standard deviation = √ 16 = 4. Q4: (4 points) Weinstein, McDermott, and Roediger (2010) conducted a study to evaluate the effectiveness of different studying strategies. The researchers asked participants to prepare for a test by reading a passage. Then, participants were split into two randomly assigned groups. In one, participants generated and answered questions after reading the passage. In the second group, students read the passage a second time. All students were

then given a test on the passage material and the researchers recorded the number of correct answers. A. Identify the dependent and independent variable for this study. Dependent value will always be the outcome whereas the independent value is what’s being manipulated to get the outcome. The independent variable in this experiment is the type of study strategy: some participants were required to read the article again while others generated and answered questions after reading the article once. The dependent variable would be considered as the exam results of each participant. B. What scale of measurement (nominal, ordinal, interval, or ratio) is used to measure the dependent variable? Although interval and ratio are similar they have characteristics that help figure out which one should be used at the appropriate time. Ratio would be the best to measure the dependent variable because it’s used when trying to measure objects like height, has an equal interval between variables, but most importantly because it has a true zero value (because of this, ratios between values can be calculated) Ratio actually has a meaning when it’s a value of zero. For example, if a participant got zero answers correct it would reflect on their grade and as a result it would hold a meaningful meaning. Q5: (2 points) In a result study, researchers collected data about the type of milk their children drank, weight, and height. The study showed that children who routinely drank reduced fat milk (1% or skim) were more likely to be overweight or obese at age 2 and age 4 compared to children who drank whole or 2% milk (Sharf, Demmer, & DBoer, 2013). Is this an example of an experimental or a correlational study? Explain. This is a correlational study because no independent variable is being manipulated as it would be if it were an experimental study. In this study, you’re simply studying the relationship the type of milk has with each child and these results would be shown on the effects the milk has on their body. Q6: (6 points total) Calculate sum of squares (SS), variance, and standard deviation for the following sample of n = 8 scores: 0, 4, 1, 3, 2, 1, 1, 4: SS = 16