Distinguish between descriptive and inferential statistics. Use examples to illustrate the points you make. (Reference using APA)2. Specify independent variable, dependent variable, the sample, population, data, and the statistic.a. A physiologist wants to know whether a particular region of thebrain (hypothalamus) is involved in the regulation of eating. Anexperiment is performed in which 30 rats are selected from theuniversity vivarium and divided into 2 groups. One of the groupsreceives lesions produced in a neutral area. After recovery from theoperations, all animals are given free access to food for 2 weeks., and arecord is kept of the daily food intake of each animal. At the end ofthe 2 week period the mean daily food intake for each group isdetermined. Finally, these means are compared to see whether the lesionsin the hypothalamus have affected the amount eaten. b. Aclinical psychologist is interested in evaluating 3 methods of treatingdepression: medication, cognitive restructuring, and exercise. A fourthtreatment condition, a waiting-only treatment group, is included toprovide a baseline control group. Sixty depressed students are recruitedfrom the undergraduate student body at a large state university, andfifteen are assigned to each treatment method. Treatments areadministered for 6 months, after which each student is given aquestionnaire designed to measure the degree of depression. Thequestionnaire is scaled from 0 to 100, with higher scores indicating ahigher degree of depression. The mean depression values are thencomputed for the 4 treatments and compared to determine the relativeeffectiveness of each treatment. c. A sport psychologist usesvisualization in promoting enhanced performance in college athletes. Sheis interested in evaluating the relative effectiveness of visualizationalone versus visualization plus appropriate self-talk. An experiment isconducted with a college basketball team. Ten members of the team areselected. Five are assigned to a visualization alone group, and five areassigned to a visualization plus self-talk group. Both techniques aredesigned to increase foul shooting accuracy. Each group practices itstechnique for 1 month. The foul shooting accuracy of each player ismeasured before and 1 month after beginning practice of the technique.Difference scores are computed for each player, and the means of thedifference scores for each group are compared to determine the relativeeffectiveness of the 2 techniques. d. A typing teacher believesthat a different arrangement of the typing keys will promote fastertyping. Twenty secretarial trainees, selected from a large businessschool, participate in an experiment designed to test this belief. Tenof the trainees learn to type on the conventional keyboard. The otherten are trained using the new arrangement of keys. At the end of thetraining period, the typing speed in words per minute of each trainee ismeasured. The mean typing speeds are then calculated for both groupsand compared to determine whether the new arrangement has had aneffect. 3. Indicate which of the following represent a variable and which a constant: a. The number of letters in the alphabet b. Number of hours in a day c. time at which you eat dinner d. number of students who major in psychology at your university each year e. number of centimeters in a meter f. the amount of sleep you get each night g. the amount you weigh h. the volume of a liter4. Identify which of the following represent continuous variables and which are discrete variables: a. Time of day c. Number of bar presses by a rat in a Skinner box e. Number of words remembered f. Weight of food eaten3. Identify the scaling of each of the following variables:a. Anxiety over public speaking, scored on a scale of 0-100 (Assume thedifference in anxiety between adjacent units throughout the scale isnot the same). b. The time it takes to react to the sound of a tone. c.Ratings of professors by students on a 50-point scale (there is aninsufficient basis for assuming equal intervals between adjacentunits).
