Ohio University Psych Statistic Experimental Methods Exam Practice
1] If Madeline wanted to know whether or not her sample results could be generalized to the population, she would use ______ statistics. If she were summarizing the data from her sample, she would use ______ statistics. inferential; descriptivedescriptive; inferentialinferential; quantitativequantitative; descriptiveProfessor Baker provided a set of in-depth instructional materials for half of the students (randomly determined) taking her experimental methods course. She then compared their test scores against those of the other half of the students who did not receive a set of instructional materials. What is the dependent variable in the study? the total number of studentsthe test scores of the studentswhether or not students got a set of instructional materialsthe difficulty of the testDr. Trebeck is testing adults to determine the effects of 3 different music tempos on how quickly the adults are able to respond in a Jeopardy-style task. The independent variable in this study is ___________.different music temposadults vs. childrentime of responding (i.e., how quickly they are able to respond)gender of the subjectsIdentify the scale of measurement for eye color (blue, black, brown, green, etc.)IntervalOrdinalRatioNominalIdentify the scale of measurement for the amount of money donated to charity in the previous tax year by one particular family.NominalOrdinalIntervalRatioIdentify the scale of measurement for the rankings of the five top-winning horses in the Kentucky Derby (i.e., 1st place, 2nd place, 3rd place, 4th place, and 5th place).NominalOrdinalRatioIntervalIdentify this variable as either measurement (quantitative) or categorical (qualitative):Brand of microwave ownedMeasurement (quantitative)Categorical (qualitative)Identify this variable as either measurement (quantitative) or categorical (qualitative): Total daily intake of caloriesMeasurement (quantitative)Categorical (qualitative)Is this variable discrete or continuous?Total time spent in sleep last nightContinuousDiscreteIs this variable discrete or continuous?GenderContinuousDiscrete"How many days per week do you sleep for a minimum of 8 hours per day? Circle Only One Number: 0 1 2 3 4 5 6 7" This type of question is an example of ___________. a closed-ended questionan open-ended questiona meta analysisa factorial analysisI am selecting people to call for jury duty. It's a small county, so I place the names of everyone who is eligible in a large hat. After mixing thoroughly, I draw 37 people to call. The sampling plan that I used is ________.systematic random samplingstratified samplingcluster samplingsimple random samplingToday, Angelica took a written test designed to measure her IQ level. Her IQ score today was 125. Last week, her IQ score on the same test was 72. This particular IQ test appears to lack _____________. reliabilityvaliditygeneralizabilitybiasWhat is the margin of error?the mistakes made by an experimenter during the sampling stagethe mistakes made by a researcher during the experimental stagethe overall measure of accuracy for an experimentthe measure of accuracy of a sample survey or pollA sample made up of volunteers may be biased because ______. the control group and the experimental group can never be equated (the margin of error is too great between the control group and the experimental group)using volunteers is often not economicalvolunteers may not be representative of the populationthe control group and the experimental group are too similarThe following type of survey question is an example of _______________. "For this survey question, please write two sentences describing your first pet." an closed-ended survey questionan open-ended survey questiona common pitfall when asking survey questionsan experiment that lacks reliability and validityDifficulties -- as well as disasters -- can occur in sampling. Which of the following is NOT an example of either a difficulty or a disaster in sampling? using the wrong sampling framenot being able to contact the individuals who have been selected for the samplegetting no response or getting a volunteer response all of the above are examples of either difficulties or disasters in samplingIdentify one of the seven pitfalls of conducting surveys for the following survey question: "Shouldn't former drug dealers be allowed to not vote in elections if they didn't sell drugs to children and they were in prison for less than 25 years or they sold drugs to adults for more than 10 years, if they expressed remorse (or if they didn't express remorse)?Asking the uninformedUnnecessary complexityOrdering of questionsConfidentiality and anonymityValidity is best described as ___________________.a measurement that is systematically off the mark in one directiona measurement that is systematically off the mark in both directionsa measurement that actually measures what it purports to measure a measurement that will give you the same consistent result time after timeIdentify one of the seven pitfalls when conducting surveys for the following survey question: "Do you agree with the experimenter of this study that capital punishment should be outlawed?" Deliberate biasConfidentiality and anonymityAsking the uninformedUnnecessary complexityUse the following set of SAMPLE data: -2 -1 2 4 5 5What is the standard deviation of this sample data set (i.e., the square root of the variance)?2.712.793.069.37Use the following set of SAMPLE data: -2 -1 2 3 6 8What is the mean of this data set? (rounded)3.672.67-3.673.17Use the following set of SAMPLE data: -2 -1 2 4 5 5What is the median?2.003.003.504.00Use the following set of SAMPLE data: -2 -1 2 4 6 9What is the range?57911Use the following set of SAMPLE data: -2 -1 2 4 5 5What is the Interquartile Range?3467Construct a Stem and Leaf plot (stemplot) using the data below. The sum (total) of the numbers that comprise the leaf in the first row is ____:11 25 22 19 23 21 17 27 21 21 23 28 10 2911171929Using the following data (which are sample exam scores), construct a Grouped Frequency Distribution on your scrap paper. 11 25 22 19 23 21 17 27 21 21 23 28 10 29 Intervals Real Limits Midpoint f cf r% c% 10 - 13 14 - 17 18 - 21 22 - 25 26 - 29What score is associated with the 50th percentile?18 - 2119.521.523Use the Grouped Frequency Distribution that you constructed on your scrap paper in the previous question to answer the following: What percentage of people scored between (and including) 26 and 29?14.29%19.72%21.43%28.57%Assume that verbal SAT scores constitute a normal distribution with a mean of 600 and a standard deviation of 100. What SAT score corresponds to the 30.85th percentile?425450550600Assume that verbal SAT scores constitute a normal distribution, with a mean of 500 and a standard deviation of 100.What percentage of scores are between 535 and 625?46.88%36.32%32.36%25.76%The scores on a PSY 1110 exam were negatively skewed. Jody scored the mean, Marcia scored the median, and Greg scored the mode. Who had the lowest score? JodyMarciaGregAll three had the same scoreThe Interquartile Range contains the middle-most _____________:1/4 of the cases1/2 of the cases3/4 of the cases9/10 of the casesWhich one of the following statements is false?The variance is the standard deviation squared, and the standard deviation is the square root of the variance.The variance can never be greater than the standard deviation.The variance is always a positive number, because it is derived by calculating the squared raw data values. The variance is a measurement of the spread between numbers in a data set. The variance measures how far each number in the set is from the mean.The following defines the normal curve:The normal curve is always unimodal; it is never bi-modal.mean = median = mode (i.e., the mean, median, and mode are all approximately the same value)The normal curve is always symmetrical.all of the aboveTransforming X values (i.e., raw data scores) into z-scores NEVER changes the shape of the distribution. True or false?TrueFalseA positive z-score always corresponds to an X value (i.e., a raw data score) that is above the mean. True or false?TrueFalseA z-score transformation is a useful statistical tool because it enables statisticians to _____:determine which scores are the best scores in a distributioncompare two or more distributions' skewnessmore easily determine the highest and lowest scores in a distributioncompare and interpret scores from virtually any distributionAssume that the µ (population mean) for a test was 50 and the σ (population standard deviation) was 4.5. Lisa scored 56 on the test, Jill had a z-score of +1.5, and Ellianna scored at the 75th percentile. Who did the best on the test (in other words, who had the highest score)? JillLisaElliannaThe performance of all three was identicalA distribution of z-scores always has a mean of _____ and a standard deviation of _____. 0, 11, 01, 10, 0Which of the following is the best interpretation of what the 65th percentile of a distribution means?65% of the scores fall equal to or above the 65th percentile65% of the scores fall equal to or below the 65th percentile65% of the scores are equal to, or fall at, the 65th percentile65% of the scores fall at the 65th percentile about 65% of the timeWhich of the following sets of correlations correctly orders the highest to lowest degree of relationship between two variables (i.e., the highest degree of relationship between two variables to the lowest degree of relationship between two variables)? -0.96, +0.72, +0.10, -0.03-0.03, +0.10, +0.72, -0.96+0.72, -0.96, +0.10, -0.03+0.72, +0.10, -0.03, -0.96Suppose a correlation between height (X) and weight (Y) for adults is +0.89. What percentage of the variability in the data is due to the relationship between height and weight? 89%67%79%25%We know that college GPA is positively correlated with salary after college. If we use knowledge of a student's GPA to predict his or her salary, the predictor variable is _______ and the criterion variable is _______. GPA; salarysalary; GPAsalary; the correlation between GPA and salaryGPA; the correlation between GPA and salaryThe following data have to do with the relationship between maternal smoking (# of cigarettes smoked per day,which is variable X) and infant birth weight (which is variable Y). (∑X, ∑X2, ∑Y, ∑Y2, and ∑XY have already beencalculated for you and are shown below in red font.)Cigarettes Per Day (X) X2 Infant Birth Weight (Y) Y2 XY2 4 7.5 56.25 15.06 36 7.2 51.84 43.210 100 6.9 47.61 69.012 144 6.2 38.44 74.414 196 5.8 33.64 81.2∑X = 44 ∑X2 = 480 ∑Y = 33.6 ∑Y2 = 227.78 ∑XY = 282.8What is COVxy (the covariance)? -1.70+1.70-2.30+2.30-3.22+3.22The following data have to do with the relationship between maternal smoking (# of cigarettes smoked per day,which is variable X) and infant birth weight (which is variable Y). (∑X, ∑X2, ∑Y, ∑Y2, and ∑XY have already beencalculated for you and are shown below in red font.)Cigarettes Per Day (X) X2 Infant Birth Weight (Y) Y2 XY2 4 7.5 56.25 15.06 36 7.2 51.84 43.210 100 6.9 47.61 69.012 144 6.2 38.44 74.414 196 5.8 33.64 81.2∑X = 44 ∑X2 = 480 ∑Y = 33.6 ∑Y2 = 227.78 ∑XY = 282.8 What is Sy (the standard deviation of Y)? In other words, the square root of the variance of the Y variable. 0.310.554.4419.670.4970.70The following data have to do with the relationship between maternal smoking (# of cigarettes smoked per day,which is variable X) and infant birth weight (which is variable Y). (∑X, ∑X2, ∑Y, ∑Y2, and ∑XY have already beencalculated for you and are shown below in red font.)Cigarettes Per Day (X) X2 Infant Birth Weight (Y) Y2 XY2 4 7.5 56.25 15.06 36 7.2 51.84 43.210 100 6.9 47.61 69.012 144 6.2 38.44 74.414 196 5.8 33.64 81.2∑X = 44 ∑X2 = 480 ∑Y = 33.6 ∑Y2 = 227.78 ∑XY = 282.8 The Pearson Correlation Coefficient (r) is: r = -0.90r = +0.90r = +0.79r = -0.79r = -0.95r = +0.95The following data have to do with the relationship between maternal smoking (# of cigarettes smoked per day,which is variable X) and infant birth weight (which is variable Y). (∑X, ∑X2, ∑Y, ∑Y2, and ∑XY have already beencalculated for you and are shown below in red font.)Cigarettes Per Day (X) X2 Infant Birth Weight (Y) Y2 XY2 4 7.5 56.25 15.06 36 7.2 51.84 43.210 100 6.9 47.61 69.012 144 6.2 38.44 74.414 196 5.8 33.64 81.2∑X = 44 ∑X2 = 480 ∑Y = 33.6 ∑Y2 = 227.78 ∑XY = 282.8 What is the slope (b)? -0.01-2.304.44-0.1419.673.22The following data have to do with the relationship between maternal smoking (# of cigarettes smoked per day,which is variable X) and infant birth weight (which is variable Y). (∑X, ∑X2, ∑Y, ∑Y2, and ∑XY have already beencalculated for you and are shown below in red font.)Cigarettes Per Day (X) X2 Infant Birth Weight (Y) Y2 XY2 4 7.5 56.25 15.06 36 7.2 51.84 43.210 100 6.9 47.61 69.012 144 6.2 38.44 74.414 196 5.8 33.64 81.2∑X = 44 ∑X2 = 480 ∑Y = 33.6 ∑Y2 = 227.78 ∑XY = 282.8 What is the y-intercept (a) for this data?6.056.677.958.3357.905.49The following data have to do with the relationship between maternal smoking (# of cigarettes smoked per day,which is variable X) and infant birth weight (which is variable Y). (∑X, ∑X2, ∑Y, ∑Y2, and ∑XY have already beencalculated for you and are shown below in red font.)Cigarettes Per Day (X) X2 Infant Birth Weight (Y) Y2 XY2 4 7.5 56.25 15.06 36 7.2 51.84 43.210 100 6.9 47.61 69.012 144 6.2 38.44 74.414 196 5.8 33.64 81.2∑X = 44 ∑X2 = 480 ∑Y = 33.6 ∑Y2 = 227.78 ∑XY = 282.8 What is the regression equation for this data?ŷ = 7.85X + (-0.12)ŷ = 8.33X + (-2.30)ŷ = 4.44X + 8.33ŷ = -0.12X + 7.85ŷ = -0.14X + 7.95ŷ = 5.49X + (-0.14)A psychologist studied self-esteem scores and found the sample data set of 57 people to be normally distributed, with a mean of 105 and a standard deviation of 6. What is the median of this distribution? 657105The median cannot be determined from the limited information given INSTRUCTIONS FOR THE following questions belowIf the question requires computation, do the calculations and then give or select the correct values using the following rule:Keep at least 4 decimal places at intermediate steps of a calculation, and round your final answer to 2 decimal places, unless otherwise noted. For example: 16.6667 would become 16.67 after roundingA survey of Ohio University students was conducted to determine if there was a particular Green that was desired by students to live on. A sample of students responses are reproduced below. Do students prefer a particular Green? Use critical value = 5.99. Use the numbers below for this question only! West Green South Green East Green 36 57 75 What is the calculated chi-squared value? A survey of Ohio University students was conducted to determine if there was a particular Green that was desired by students to live on. A sample of students responses are reproduced below. Do students prefer a particular Green? Use critical value = 5.99. Use the numbers below for this question only! West Green South Green East Green 26 66 115 What would the expected value for the West Green be? A local sports bar wanted to determine whether Ohio University students prefer a particular type of food in their establishment. A sample of students responses are reproduced below. Do students prefer a particular type of bar food? Use critical value = 6.58. Use the numbers below for this question only! Nachos Pizza Chicken Wings Cheese Sticks 31 40 37 47 What would the expected value for Cheese Sticks be? A local sports bar wanted to determine whether Ohio University students prefer a particular type of food in their establishment. A sample of students responses are reproduced below. Do students prefer a particular type of bar food? Use critical value = 6.58. Use the numbers below for this question only! Nachos Pizza Chicken Wings Cheese Sticks 40 37 39 44 What is the calculated chi-squared value? Using a critical value of 6.58, was there a significant preference for what students eat in a sports bar based on the obtained chi-square value in Question 5? Yes NoIn a study of binge drinking among undergraduates at Ohio University, a researcher was interested in gender differences as related to binge drinking and to drinking-related arrests. She wanted to know two things: (a) Is there a significant relationship between gender and binge drinking (as defined by 5 or more drinks at one sitting), and (b) Is there a significant relationship between gender and drinking-related arrests? A random sample of males and females were asked about their experiences with binge drinking and with drinking-related arrests. Use the numbers below for this question only! Binge Drinking? YES NO Male 215 270 Female 216 235 What would the expected value for the "male-yes" cell be? In a study of binge drinking among undergraduates at Ohio University, a researcher was interested in gender differences as related to binge drinking and to drinking-related arrests. She wanted to know two things: (a) Is there a significant relationship between gender and binge drinking (as defined by 5 or more drinks at one sitting), and (b) Is there a significant relationship between gender and drinking-related arrests? A random sample of males and females were asked about their experiences with binge drinking and with drinking-related arrests. Use the numbers below for this question only! Binge Drinking? YES NO Male 256 224 Female 272 235 What would the expected value for the "female-no" cell be? In a study of binge drinking among undergraduates at Ohio University, a researcher was interested in gender differences as related to binge drinking and to drinking-related arrests. She wanted to know two things: (a) Is there a significant relationship between gender and binge drinking (as defined by 5 or more drinks at one sitting), and (b) Is there a significant relationship between gender and drinking-related arrests? A random sample of males and females were asked about their experiences with binge drinking and with drinking-related arrests. Test for a relationship in the following data: Use the numbers below for this question only! Binge Drinking? YES NO Male 44 27 Female 24 49 What is the calculated chi-squared value? Using a critical value of 3.84, and based on the obtained chi-square value in Question 9, is there a significant relationship between gender and binge drinking? Yes NoIn a study of binge drinking among undergraduates at Ohio University, a researcher was interested in gender differences as related to binge drinking and to drinking-related arrests. She wanted to know two things: (a) Is there a significant relationship between gender and binge drinking (as defined by 5 or more drinks at one sitting), and (b) Is there a significant relationship between gender and drinking-related arrests? A random sample of males and females were asked about their experiences with binge drinking and with drinking-related arrests.Use the numbers below for this question only! Experience Alcohol-related Arrest? YES NO Male 219 278 Female 229 232What would the expected value for the "male-no" cell be?In a study of binge drinking among undergraduates at Ohio University, a researcher was interested in gender differences as related to binge drinking and to drinking-related arrests. She wanted to know two things: (a) Is there a significant relationship between gender and binge drinking (as defined by 5 or more drinks at one sitting), and (b) Is there a significant relationship between gender and drinking-related arrests? A random sample of males and females were asked about their experiences with binge drinking and with drinking-related arrests. Use the numbers below for this question only! Experience Alcohol-related Arrest? YES NO Male 201 235 Female 263 261 What would the expected value for the "female-yes" cell be? In a study of binge drinking among undergraduates at Ohio University, a researcher was interested in gender differences as related to binge drinking and to drinking-related arrests. She wanted to know two things: (a) Is there a significant relationship between gender and binge drinking (as defined by 5 or more drinks at one sitting), and (b) Is there a significant relationship between gender and drinking-related arrests? A random sample of males and females were asked about their experiences with binge drinking and with drinking-related arrests. Test for a relationship in the following data: Use the numbers below for this question only! Experience Alcohol-related Arrest? YES NO Male 45 23 Female 25 51 What is the calculated chi-squared value? Using a critical value of 3.84, and based on the obtained chi-square value in Question 13, is there a significant relationship between gender and alcohol-related arrests? Yes NoWhich of the following is not a true statement about bar graphs?The horizontal axis does not need to be labeled for a bar graph.Bar graphs show percentages or frequencies in various categories.Bar graphs represent categorical data.Pictograms are similar to bar graphs except they use pictures related to the topic.Papa Johns conducted a survey of 100 nursing students taking statistics to determine what toppings they preferred on their pizza. Data handlers converted students' responses into a pie (no pun intended) chart to display the results clearly to upper management. Did the data handlers do a good job in constructing a quality statistical picture? Examine the statistical picture below and if you see a feature that is problematic (e.g., inaccurate or misleading), place your cursor over that feature and click. If you change your mind, click on the clear button on the bottom left and you can begin again. If you decide the statistical picture contains no problematic features, click just above the word "cheese." (Hint: Check out the components of a well-designed statistical picture that are listed on page 7 of the Module 6 course notes, such as appropriate Title, correct Source, etc.)If you are having problems getting your choice to register and save, then you are probably not using the Firefox browser. Switching to the Firefox browser should remedy the problem. If the problem persists, let your moderator know what your choice is BEFORE THE ASSIGNMENT DEADLINE!