Robert A. Haaf

University of Toledo, Toledo, OH, United States

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Publications (19)16.5 Total impact

  • Anne L. Fulkerson, Robert A. Haaf
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    ABSTRACT: An experiment with 64 twelve-month-olds investigated the influence of object naming on their formation of novel object categories. Stimuli were constructed to represent 2 broad categories consisting of 3 narrow categories each. Objects representing the same narrow or broad category were presented with either a labelling or non-labelling phrase in a modified word extension procedure. Only infants in the narrow category-level condition who heard labelling phrases demonstrated categorization, and categorization performance in the narrow label condition was superior to that in the narrow no-label condition. Consistent with studies utilizing conventional objects, results indicate that object naming can facilitate infants' formation of novel object categories early in the process of lexical acquisition.
    First Language 01/2006; 26(4):347-361.
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    ABSTRACT: The present research investigated attention to and recognition of components in compound stimuli by infants and preschool children. A preliminary experiment was conducted with adults to develop stimulus components and to validate their structure. An experiment using an oddity task with preschoolers (N = 32) and one using the familiarization/novelty-preference task with infants (N = 64) demonstrated successful discrimination among the stimulus components on the basis of edge property information. Separate experiments using a matching task with preschoolers (N = 32) and an habituation task with infants (N = 32) demonstrated that preschoolers and infants are also able to direct attention to and recognize components of compound stimuli. Implications for structural-description theories of object recognition are discussed.
    Journal of Experimental Child Psychology 11/2003; 86(2):108-23. · 3.12 Impact Factor
  • Anne L. Fulkerson, Robert A. Haaf
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    ABSTRACT: This experiment examines the joint influence of auditory and social cues on infants' basic-level and global categorization. Nine- and fifteen-month-olds were familiarized to a series of category exemplars in an object-examining task. Objects were introduced with a labeling phrase, a non-labeling sound, or no sound, and auditory input was presented orally by the experimenter or played on a hidden voice recorder. Novel objects from the familiarized category and a contrasting category were then presented. Results of analyses performed on novelty preference scores indicated that infants demonstrated basic-level categorization in all conditions. However, infants at both age levels only demonstrated global categorization when labeling phrases were introduced. In addition, labels led to global categorization in 9-month-olds regardless of the source of those labels; however, labels only led to global categorization in 15-month-olds when the labels were presented orally by the experimenter.
    Infancy 01/2003; 4(3):349-369. · 1.73 Impact Factor
  • BRENDA L. LUNDY, JAY W. JACKSON, ROBERT A. HAAF
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    ABSTRACT: The present research explored 3-, 7-, and 10-yr.-old children's face recognition in a "paraphernalia-to-fool" paradigm in which angular size of the stimuli was manipulated. It was proposed that, given the attentional limitations of the two youngest age groups, facial information and irrelevant paraphernalia would be perceived as an undifferentiated whole in stimuli of small visual angles, resulting in decreased recognition. However, increasing angular size should enable the 7-yr.-olds to differentiate the two types of stimulus information more easily. Therefore, it was hypothesized that the influence of paraphernalia on 7-yr.-olds' performance would be moderated by the spatial size of the stimulus. The effect of angular size was also expected to interact with age group. As predicted, 10-yr.-olds were unaffected by the size manipulation, 7-yr.-olds' performance was moderated by angular size, and, although 3-yr.-olds' recognition improved with large stimuli, the increase was not significant. Results are discussed in relation to the influence of stimulus properties and age-related attentional limitations.
    Perceptual and Motor Skills 07/2001; 92(3 Pt 1):919-29. · 0.49 Impact Factor
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    J T Coldren, R A Haaf
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    ABSTRACT: Three experiments were performed to test whether infants show a bias for detecting the presence of a feature in a stimulus rather than its absence. In the 1st experiment, 24 16-week-old infants were given 3 paired-comparison problems, each of which included a 25-s familiarization phase followed by 2 test trials. Infants were familiarized to 1 member of a set of capital alphabetical letters (E-F; Q-O; B-R). Then they were given a paired-comparison recognition test under 1 of 2 conditions. In the feature-present condition, the familiar letter (e.g., F) was paired with a novel letter containing the addition of a distinguishing element (e.g., E). In the feature-absent condition, infants were presented with a familiar letter (e.g., E) paired with a novel letter in which 1 element was removed (e.g., F). Infants showed a novelty preference to the letter in which the distinguishing feature was present, but there was no preference for novelty in the feature-absent condition. The 2nd experiment showed that infants' fixation to the letter containing the presence of the feature was not due to a simple preference for the letter with the greater number of elements. Finally, to test whether infants' failure to discriminate the absence was due to insufficient encoding time, 36 infants were tested in a 3rd experiment in which familiarization time was varied. After 20 s of familiarization, no evidence of discrimination was observed in either the feature-present or feature-absent condition. After 30 s, however, infants could discriminate the novel letter in the feature-present condition but not in the feature-absent condition. The significance of these results is discussed in terms of theoretical explanations for the development of the feature-presence bias.
    The Journal of Genetic Psychology 01/2001; 161(4):420-34. · 0.83 Impact Factor
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    ABSTRACT: This study was undertaken to examine whether alleged child sexual abuse perpetrators are handled differently by the courts than other alleged felony perpetrators. Comparisons were made from the time of prosecutorial case acceptance through prosecution to sentencing, with emphasis on judicial and prosecutorial decision-making and plea-bargaining. Data were retrospectively abstracted on the entire defendant population of cases of sexual abuse of children and adolescents (ages 2-17) over a 5-year period. Using a case-flow analysis, comparisons were made between a child sexual abuse cohort and a cohort of matched felony cases from a single jurisdiction. Three important findings emerged. First, compared to other felons, abuse perpetrators were employed, had been married, were mostly European American, and were older than 30 years of age. Second, in the abuse cohort, as many as 14% had a previous sexual or violent record compared to 2% in the comparison group. Third, similar percentages of perpetrators in both groups were released on their own recognizance, had the charges against them dropped, and were found guilty. As well, no differences between groups were found in the proportion of individuals sentenced to jail, probation, counseling, or work release. Although the treatment of perpetrators of child sexual abuse was similar to the treatment of perpetrators of other felonies, the profile of the child abuse perpetrator was quite different. Knowledge about this profile may impact prosecution or treatment and recidivism rates, to the extent that recidivism is related to characteristics of the abuse perpetrator.
    Child Abuse & Neglect 05/2000; 24(4):569-77. · 2.47 Impact Factor
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    ABSTRACT: Objective: This study was undertaken to examine whether alleged child sexual abuse perpetrators are handled differently by the courts than other alleged felony perpetrators. Comparisons were made from the time of prosecutorial case acceptance through prosecution to sentencing, with emphasis on judicial and prosecutorial decision-making and plea-bargaining.Method: Data were retrospectively abstracted on the entire defendant population of cases of sexual abuse of children and adolescents (ages 2–17) over a 5-year period. Using a case-flow analysis, comparisons were made between a child sexual abuse cohort and a cohort of matched felony cases from a single jurisdiction.Results: Three important findings emerged. First, compared to other felons, abuse perpetrators were employed, had been married, were mostly European American, and were older than 30 years of age. Second, in the abuse cohort, as many as 14% had a previous sexual or violent record compared to 2% in the comparison group. Third, similar percentages of perpetrators in both groups were released on their own recognizance, had the charges against them dropped, and were found guilty. As well, no differences between groups were found in the proportion of individuals sentenced to jail, probation, counseling, or work release.Conclusions: Although the treatment of perpetrators of child sexual abuse was similar to the treatment of perpetrators of other felonies, the profile of the child abuse perpetrator was quite different. Knowledge about this profile may impact prosecution or treatment and recidivism rates, to the extent that recidivism is related to characteristics of the abuse perpetrator.
    Child Abuse & Neglect 04/2000; 24(4):569-577. · 2.47 Impact Factor
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    ABSTRACT: Recognition of a visual stimulus was assessed under two same- and two different-context conditions. Results indicate: (a) following brief familiarization, recognition of a visual stimulus is context-sensitive regardless of whether contextual cues are visual or auditory, and (b) recognition failure under different-context conditions results from change in context rather than from unfamiliar-cue distraction.
    Infant Behavior and Development 01/2000; · 1.67 Impact Factor
  • Robert A. Haaf
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    ABSTRACT: The present experiment was designed to investigate the priority with which 6-month-olds attend to stimuli containing both contextual and target information. The procedure involved a familiarization phase to a stimulus that contained a central target cue and a surrounding context followed by paired comparison novelty tests. Results indicate that when infants monitor the environment, background context cues receive attentional priority over target cues.
    Infant Behavior & Development - INFANT BEHAV DEVELOP. 01/1999; 22(1):131-135.
  • Anne L. Fulkerson, Robert A. Haaf
    Infant Behavior & Development - INFANT BEHAV DEVELOP. 01/1998; 21:419-419.
  • Infant Behavior & Development - INFANT BEHAV DEVELOP. 01/1998; 21:618-618.
  • Infant Behavior and Development 04/1996; 19:800-800. · 1.67 Impact Factor
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    ABSTRACT: Four experiments were conducted using stimuli that included a central stimulus cue and a background context pattern. At issue was how attention, encoding, and recognition are affected when these stimulus components are manipulated within habituation, familiarization, and recognition procedures. Results indicate that infants attend to and encode both stimulus components (cue, context pattern), and that these components are encoded interactively. That is, infants encode cue information in relation to the context (setting) in which it is experienced. Results also indicate that recognition is context dependent under some experimental conditions, with successful recognition exhibited only when encoding and retrieval contexts are identical. Nevertheless, factors that influence the deployment of attention to context patterns also determine whether cue recognition is cintext dependent or not. Results were discussed in terms of the importance of attentional processes in infants' monitoring of the visual world and in terms of theoretical issues related to attentional deployment in infants.
    Infant Behavior & Development - INFANT BEHAV DEVELOP. 01/1996; 19(1):93-106.
  • Jeffrey T. Coldren, Robert A. Haaf
    Infant Behavior & Development - INFANT BEHAV DEVELOP. 01/1996; 19:401-401.
  • Robert A Haaf
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    ABSTRACT: Three experiments were conducted to investigate the response of 10-week-old infants to the configuration of features in facelike patterns. In each experiment a series of preview trials was shown before. facelike patterns were presented on test trials. Preview stimuli were schematic drawings with non-facial configurations (Experiment 1), schematic drawings with facial configurations (Experiment 2), or photographs of men's and women's faces (Experiment 3). Test stimuli in all three experiments were facelike drawings that differed in the number and the configuration of their stimulus features.
    Visual Cognition 10/1994; 1(4):475-488. · 2.05 Impact Factor
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    ABSTRACT: Forty-eight pairs of observers recorded fixations during three test sessions. In each session an adult subject executed a predetermined sequence of fixations for 15 20-s trials. Three factors were investigated: Viewing Condition (live vs. videotaped subject). Number of Stimulus Apertures (1, 2, 4) and Subject Eye Color (blue, brown). Results indicated that training procedures which focus on observer agreement generally lead to acceptable levels of accuracy. However, certain procedural variations affect observer accuracy and observer agreement in different ways. Likewise, certain experimental procedures are particularly demanding in terms of observer accuracy.
    Infant Behavior and Development. 01/1989;
  • Robert A Haaf
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    ABSTRACT: The purpose of this experiment was to determine whether infants at 5 and at 10 weeks of age respond to facelike drawings on the basis of stimulus complexity or on the basis of degree of resemblance to the human face. Twenty-four Ss at each age were shown four patterns in which these two dimensions were varied orthogonally. Fixation time was recorded using the successive, single stimulus procedure. Results provided no evidence of response to the facial resemblance dimension at either age level. However, there was a significant complexity component in the responses of both groups. The 5-week-old infants preferred an intermediate level of stimulus complexity. Those at 10 weeks showed a linear preference for increasing levels of the complexity dimension.
    Journal of Experimental Child Psychology. 01/1974;
  • Source
    Stacey S Shull, Julie M Hupp, Robert A Haaf
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    ABSTRACT: Navon (1977) suggests that people extract global information before local information when looking at objects. This study evaluates how familiarity affects global-local processing. Participants were asked whether a target letter was present in various stimuli. This study gives further support that familiarity may dictate how people allocate their attention to stimuli. Introduction Navon (1977, 1981) suggests that people notice global information before local information when observing objects. For example, an object is noticed as a car before its individual features are noticed (e.g. wheels and doors). He asserted that all properties of the global and local features (i.e. complexity, salience, familiarity) must be controlled in order to find global precedence. Learning how these properties affect the global precedence hypothesis will help in understanding why global precedence occurs. Several researchers have explored how properties affect global precedence. For example, Kinchla & Wolfe (1979) studied the effect of stimulus size and the found that global precedence only occurs when the visual angle of a stimulus is smaller than 6-9°, therefore concluding that size matters. Also, hemispheric differences have been found to affect processing of global-local stimuli (Christman & Weiner, 1997) . Regan (1981) studied differences in performance when learning to name letters using both familiar stimuli (English letters) and unfamiliar stimuli (Armenian letters). Both large English and large Armenian letters delayed naming small letters, however there was no interference when the large letter was the same as the one to be named. Shull, Hupp, and Haaf (2002) found that familiarity affected how participants allocated their attention to stimuli. The current study strengthens this find by replicating with a shorter presentation duration. Method 24 adults viewed 10 stimuli, ten times each. Each stimulus consisted of small local elements that made up a larger global figure (see figure 1). Each stimulus was either familiar at both levels, familiar at local while novel at global, or novel at local while familiar at global. Participants sat with their chin in a chin rest, 60cm from the computer screen, viewing the stimulus from a 9° visual angle. They first heard a target letter, either an H or an F, then saw a stimulus for 100 msec. They were asked to respond as quickly and accurately as possible, by hitting a button if the target letter was located in the stimulus. This design was identical to Shull, Hupp, and Haaf (2002) except for a change in the presentation duration from 1000 msec to 100 msec. This decrease allows the results to be more comparable to the design of previous research in the area. The independent variables were the level of familiarity of the stimuli and whether the target was present or absent. The dependent variables were reaction time and the number of correct responses given.
  • Psychology Faculty Publications.

Publication Stats

106 Citations
16.50 Total Impact Points

Institutions

  • 1974–2003
    • University of Toledo
      • Department of Psychology
      Toledo, OH, United States
  • 2001
    • Youngstown State University
      • Department of Psychology
      Youngstown, OH, United States
    • Indiana University-Purdue University Fort Wayne
      • Department of Psychology
      Fort Wayne, IN, United States
  • 2000
    • Medical University of Ohio at Toledo
      Toledo, Ohio, United States