The construction and validation of an instrument to measure classroom adjustment.

Thesis (Ed.D.)--Boston University.I. Problem: To construct a measure of classroom adjustment which would be easily administered and interpreted by the classroom teacher. II. Procedure: A. Two measures were developed; an 86 item Teacher Checklist and a 40 item Parent Rating Scale. 1. Classroom teachers were asked to submit situations which would give evidence of good classroom adjustment. Ten trait categories were established as follows: concentration, cooperation, courtesy, emotional stability, friendliness, health, initiative, responsib- ility, self-confidence and self-reliance. A list of 86 items, to check the child's performance in these trait areas was complied. i.e. "He is wiilling to lead Opening Exercises (initiative)." Any item which could not be objectively observed was discarded. For ease of checking, the 86 items were so arranged as to follow the routine of a normal classroom day. Each child was rated twice on the Checklist. In 12 classrooms, (299 children) the child was rated by his own teacher first, then by a second person. In 4 classrooms (101 children) the child's teacher did both ratings with a lapse of 4 weeks between the two. 2. The Parent Rating Scale again attempted to get evidence on the same ten traits. i.e. "He can shop by himself (Initiative)." The parents were asked to check each item as "Usually, Often or Occasionally." B. Four hundred first grade children who participated in the study were administered the following tests: 1. Otis Quick Scoring J.iental Ability Test. 2. The Teacher Checklist of Adjustment. 3. The Parent Rating Scale was filled out by parents of the children. 4. The Detroit Word Recognition Test and the Boston University Reading Tests were used to measure reading achievement. III. Major Findings and Conclusions: A. Teachers and parents found both measures were easily administered. B. Reliability was established as follows: 1. For the Teacher Checklist a. Correlation between 2 raters was .73. b. Correlation on same rater twice was .97. c. Split half reliability for whole test corrected by Spearman Brown Formula was .96. d. Item analysis revealed significant differences for 81 out of 86 items for high and low scorers. 2. For the Parent Rating Scale· a. Split half correlation on whole.test, corrected by Spearman Brown Formula, was .70. b. Item analysis revealed significant differences on 24 of the 40 items. c. The Parent Rating Scale did not correlate significantly with the Teacher Checklist (.16). C. Relation of Adjustment to Reading Achievement 1. Positive Correlations of .48 and ·57 were found between adjustment and reading achievement. 2. Children were divided on the basis of adjustment scores into three groups--high, middle and low. a. The means of these three groups on the Detroit Word Recognition Test were 25.76, 19.00 and 13.80, respectively. Means on the Boston University Test were 88.3, 52.0 and 40.5, respectively. The differenees in achievement were statistically significant between high and middle as well as between middle and low groups. b. The mean mental age for the high group was 90.5 months, for the middle 82.5 and for the low 80.0. c. The difference in mental age between the high and the middle group was very significant but the difference between the middle and low groups was not significant. d. The mean IQ's were 118, 107 and 105 for high, middle and low groups, respectively. The difference between the high and middle groups was statistically significant but this was not true between the middle and low groups

Superconducting proximity effect in interacting double-dot systems

We study subgap transport from a superconductor through a double quantum dot with large on-site Coulomb repulsion to two normal leads. Non-local superconducting correlations in the double dot are induced by the proximity to the superconducting lead, detectable in non-local Andreev transport that splits Cooper pairs in locally separated, spin-entangled electrons. We find that the $I$--$V$ characteristics are strongly asymmetric: for a large bias voltage of certain polarity, transport is blocked by populating the double dot with states whose spin symmetry is incompatible with the superconductor. Furthermore, by tuning gate voltages one has access to splitting of the Andreev excitation energies, which is visible in the differential conductance.Comment: 5 pages, 4 figure

Evaluating the impact of binary parameter uncertainty on stellar population properties

Binary stars have been shown to have a substantial impact on the integrated light of stellar populations, particularly at low metallicity and early ages - conditions prevalent in the distant Universe. But the fraction of stars in stellar multiples as a function of mass, their likely initial periods and distribution of mass ratios are all known empirically from observations only in the local Universe. Each has associated uncertainties. We explore the impact of these uncertainties in binary parameters on the properties of integrated stellar populations, considering which properties and timescales are most susceptible to uncertainty introduced by binary fractions and whether observations of the integrated light might be sufficient to determine binary parameters. We conclude that the effects of uncertainty in the empirical binary parameter distributions are likely smaller than those introduced by metallicity and stellar population age uncertainties for observational data. We identify emission in the He II 1640Å emission line and continuum colour in the ultraviolet-optical as potential indicators of a high mass binary presence, although poorly constrained metallicity, dust extinction and degeneracies in plausible star formation history are likely to swamp any measurable signal

Mud Pies

https://digitalcommons.library.umaine.edu/mmb-vp/4541/thumbnail.jp

Characterizing Supernova Progenitors via the Metallicities of their Host Galaxies, from Poor Dwarfs to Rich Spirals

We investigate how the different types of supernovae are relatively affected by the metallicity of their host galaxy. We match the SAI Supernova Catalog to the SDSS-DR4 catalog of star-forming galaxies with measured metallicities. These supernova host galaxies span a range of oxygen abundance from 12 + log(O/H) = 7.9 to 9.3 (~ 0.1 to 2.7 solar) and a range in absolute magnitude from MB = -15.2 to -22.2. To reduce the various observational biases, we select a subsample of well-characterized supernovae in the redshift range from 0.01 to 0.04, which leaves us with 58 SN II, 19 Ib/c, and 38 Ia. We find strong evidence that SN Ib/c are occurring in higher-metallicity host galaxies than SN II, while we see no effect for SN Ia relative to SN II. We note some extreme and interesting supernova-host pairs, including the metal-poor (~ 1/4 solar) host of the recent SN Ia 2007bk, where the supernova was found well outside of this dwarf galaxy. To extend the luminosity range of supernova hosts to even fainter galaxies, we also match all the historical supernovae with z < 0.3 to the SDSS-DR6 sky images, resulting in 1225 matches. This allows us to identify some even more extreme cases, such as the recent SN Ic 2007bg, where the likely host of this hypernova-like event has an absolute magnitude MB ~ -12, making it one of the least-luminous supernova hosts ever observed. This low-luminosity host is certain to be very metal poor (~ 1/20 solar), and therefore this supernova is an excellent candidate for association with an off-axis GRB. The two catalogs that we have constructed are available online and will be updated regularly. Finally, we discuss various implications of our findings for understanding supernova progenitors and their host galaxies.Comment: ApJ accepted, 26 pages, 5 figures, 1 table. Updated catalogs are available at http://www.astronomy.ohio-state.edu/~prieto/snhosts