True/False Questions

Question 11 pts Descriptive statistics involves characterizing the obtained data. True False   Question 21 pts True experiments involve the manipulation of variables by the investigator. True False   Question 31 pts The method of authority is opposed to the scientific method. True False   Question 41 pts Data are an indispensable part of scientific method. True False   Question 51 pts In an experiment conducted to determine the effect of testosterone on aggression, testosterone is the independent variable. True False   Question 61 pts When doing summation, the number above the summation sign indicates the term ending the summation and the number below indicates the beginning term. True False   Question 71 pts If IQ was measured on a ratio scale, and John had an IQ of 40 and Fred an IQ of 80, it would be correct to say that Fred was twice as intelligent as John. True False   Question 81 pts Measurement is always approximate with a continuous variable. True False   Question 91 pts In rounding, if the remainder beyond the last digit is greater than 1/2, add one to the last digit. If the remainder is less than 1/2, leave the last digit as it is. True False   Question 101 pts The number of students in a class is an example of a continuous variable. True False   Question 111 pts The real limits of a discrete variable are those values that are above and below the recorded value by one half of the smallest measuring unit of the scale. True False   Question 121 pts In grouping scores, the wider the intervals, the more information that is lost. True False   Question 131 pts Any percentile point for a distribution of scores must have a value equal to one of the scores. True False   Question 141 pts If a curve is negatively skewed, most of the scores occur at the higher values and the curve tails off toward the lower end of the horizontal axis. True False   Question 151 pts A frequency distribution of grouped scores is used for distributions that have relatively few scores to stretch them out. True False   Question 161 pts A stem and leaf diagram contains more information than a histogram. True False   Question 171 pts The median and the 50th percentile rank score will always have the same value. True False   Question 181 pts When calculating the population standard deviation, we use N  1 in the denominator. True False   Question 191 pts Central tendency describes the central location of the set of scores. True False   Question 201 pts If the number of raw scores is odd, the median is always the score in the middle position. True False   Question 211 pts In a bell-shaped distribution, the mean, median and mode will be equal. True False   Question 221 pts For data that are not normally distributed, the standard deviation will sometimes be negative. True False   Question 231 pts A z score designates how many standard deviations the raw score is above or below the mean. True False   Question 241 pts The normal curve reaches the horizontal axis in 4 standard deviations above and below the mean. True False   Question 251 pts It is impossible to have a z score of 30.2 True False   Question 261 pts The area beyond a z score of 1.12 is the same as the area beyond a z score of 1.12. True False   Question 271 pts A raw score that is 1 standard deviation above the mean of the raw score distribution will have a z score of 1. True False   Question 281 pts Correlation implies causation. True False   Question 291 pts The range of a correlation coefficient is 0 to +1. True False   Question 301 pts Pearson r requires that the data be of interval or ratio scaling. True False   Question 311 pts Rho is used where one or both variables are at least of interval scaling. True False   Question 321 pts In general, the regression line for predicting X given Y is the same as the regression line for predicting Y given X. True False   Question 331 pts An imperfect relationship generally yields exact prediction. True False   Question 341 pts Properly speaking, we should limit our predictions to the range of the base data. True False   Question 351 pts To do linear regression, there must be paired scores on two variables. True False   Question 361 pts If the correlation between two variables is 1.00, the standard error of estimate equals 0. True False   Question 371 pts When a sampled score is put back in the population before selecting the next score, this process is called sampling without replacement. True False   Question 381 pts Probability values range from 0 to 1. True False   Question 391 pts The Addition Rule concerns one of several possible events. True False   Question 401 pts When a variable is continuous, p(A) equals the area under the curve corresponding toA divided by the total area under the curve. True False   Question 411 pts If an event is certain to occur, its probability of occurrence equals 1.00. True False   Question 421 pts We always evaluate just the specific result obtained in the experiment. True False   Question 431 pts The sign test analyzes both the magnitude and direction of the data. True False   Question 441 pts If the result turns out to be in the direction opposite to a directional H1, we must conclude by retaining H0. True False   Question 451 pts It is impossible to prove with certainty the truth of H1 when using sample data. True False   Question 461 pts If alpha is made more stringent, beta increases. True False   Question 471 pts If H0 is true, as the power of the experiment increases, the probability of rejecting H0increases. True False   Question 481 pts Increasing N increases the probability of a Type II error. True False   Question 491 pts Other factors held constant, a one-tailed test is more powerful than a two-tailed test. True False   Question 501 pts High power is desirable in an experiment. True False   Question 511 pts Decreasing beta will generally cause  to increase. True False   Question 521 pts The degrees of freedom equal N  1 for the t test for single samples. True False   Question 531 pts The t test requires that the sampling distribution of t be normally distributed. True False   Question 541 pts Generally speaking, the more confidence we have that the interval contains the population mean, the larger is the interval. True False   Question 551 pts In general, if r = 0, then  = 0. True False