The Commissioner of Labor and Industries (commissioner) set fiscal year 19834 wage rates for the Boston Housing Authority (BHA), pursuant to his authority under G. L. c. 121B, § 29, and G. L. c. 149, § 26. The BHA and the Cambridge Housing Authority (CHA) successfully challenged those rates in the Superior Court, which remanded the rates to the commissioner for redetermination. The commissioner redetermined the rates and then brought a separate action in the Superior Court to enforce them. That court consolidated the two cases, and, on motion of the commissioner, ordered summary judgment in his favor in the enforcement action. The BHA appeals from this judgment. The commissioner and the Massachusetts Laborers’ District Council appeal from the Superior Court’s original judgment remanding the rates for redetermination. We granted an application for direct appellate review. We hold that the judgment in the first action, remanding the rates to the commissioner for redetermination, was correct and should be affirmed. In the second action, we conclude that summary judgment should not have been entered in favor of the commissioner. Some rates must be determined once again because the commissioner failed to calculate them pursuant to standards prescribed by G. L. c. 149, § 26. As to the remaining rates, we remand the case to the Superior Court for further proceedings, because the BHA’s challenge to the commissioner’s method for assessing job comparability raised a disputed issue of material fact.

*52The essential facts are not in dispute. The BHA owns and operates over 18,000 apartments in sixty-seven housing developments, and employs approximately 350 workers to maintain them. The CHA owns and operates approximately 3,000 apartments in twenty-five housing developments, and employs seventy workers to maintain them. Both authorities are subject to collective bargaining agreements that set the wage rates for all maintenance employees at the levels determined by the commissioner under G. L. c. 121B, § 29.

In January, 1982, the BHA and the CHA requested the commissioner to set wage rates for fiscal year 1983.3 *5 The commissioner “mechanical[ly]” established wage rates for housing authority positions with counterparts in the construction industry (e.g., carpenters, electricians, plumbers, painters and laborers) at eighty per cent of the prevailing wage of similarly titled unionized workers in the construction industry. For housing authority positions with no construction industry analogue (e.g., appliance men, firemen, and auto mechanics), the commissioner set wage rates at eighty per cent of the prevailing wage for unionized construction industry laborers, plus various amounts.6

The BHA and the CHA complained that these rates were too high for the work performed by their employees and asked the commissioner to reconsider.7 When he declined to reconsider, the BHA brought suit. The CHA intervened as a plaintiff, and the Massachusetts Laborers District Council intervened as *53a defendant. The housing authorities argued primarily that the work performed by their maintenance workers was not comparable to work performed in the construction industry, and that the commissioner was required to adjust the wage rates accordingly.

The Superior Court judge enjoined enforcement of the new rates on August 6, 1982.8 On March 9, 1983, he held that the wage rates were arbitrary, and ordered the commissioner to redetermine them, finding that “the jobs performed by construction trade workers are vastly different from the jobs performed by the BHA[’s] and the CHA’s maintenance workers.” The judge held that the Legislature intended the eighty per cent figure to be applied only to comparable positions, and that “in order to determine the comparability of certain work it is necessary to look beyond a job title or description and to the entire milieu of the work environment which includes such factors as hazards, difficulty of tasks, physical effort, job security, frequency of tasks, continuity, and all forms of compensation and other perquisites.”9

*54The commissioner then conducted a job comparability study on which he based a new set of wage rates. For positions with analogues in the construction industry, the commissioner again based the new wage rates solely on collective bargaining agreements in the construction industry. For positions that had no analogues in the construction industry, the commissioner based the new wage rates on collective bargaining agreements outside the construction industry. The redetermined wage rates were issued in December, 1983, and, in most cases, were either the same or higher than the original rates. The Commonwealth brought suit thereafter to enforce the redetermined wage rates, and the judge granted its motion for summary judgment on August 17, 1984. The judge concluded that the wage rates were a “regulation,” and thus that he was required to uphold them if they were supported by a rational basis. The judge ruled that, although there were some methodological shortcomings in the commissioner’s job comparability study, it provided a sufficient rational basis for the determined wage rates.

1. The commissioner argues that, at least as to housing authority workers with counterparts in the construction industry, he is required under G. L. c. 121B, § 29, and G. L. c. 149, § 26, to base housing authority wage rates solely on the wages set in collective bargaining agreements between unionized workers and the private construction industry. The commissioner has misinterpreted the relevant provisions of G. L. c. 149, § 26, and has thereby ignored nonprivate and nonconstruction wage agreements on which the housing authority wage rates should be based.

General Laws c. 121B, § 29 (1984 ed.), provides that the commissioner shall set minimum wage rates for “architects, technical engineers, draftsmen, technicians, laborers and mechanics” employed by housing authorities, and that these wage rates shall be fixed “at no less than eighty per cent of the prevailing wage” as determined in accordance with G. L. c. 149, §§ 26 and 27. General Laws c. 149, § 26, which also governs generally the setting of wage rates for persons employed in the construction of public works, has four provisos *55for determining those rates.10 Interpreted in the context of this case, two are applicable.11 In accordance with the third proviso, wage rates for any trade or occupation may not be less than eighty per cent of wage rates that have been established by collective bargaining agreements “between organized labor and employers” in the municipality where the housing authority is located. By the terms of the fourth proviso, when no such rates have been established in the municipality where the housing authority is located, the wage rates may not be less than eighty per cent of wage rates paid to employees engaged in the same trade or occupation by “private employers engaged in the construction industry.”

The commissioner claims that, for housing authority positions with counterparts in the construction industry (i.e., carpenters, plumbers), the two statutes require that the “prevailing wage” be determined solely by reference to collective bargaining agreements in the private construction industry. This interpretation, however, contradicts the words of G. L. c. 149, *56§ 26, because it combines elements of the third and fourth provisos. By the third proviso, the commissioner must first refer to collective bargaining agreements “between organized labor and employers” (emphasis supplied). Only when “no such . . . rates have been . . . established,” is he to turn to the fourth proviso, where he is directed to consider wages paid “by private employers engaged in the construction industry” (emphasis supplied). These specific references in the fourth proviso show an intention that the generic word “employers” in the third proviso means something more than “private” employers or those “engaged in the construction industry.” By the terms of the third proviso, the commissioner must consider first all employers — both public and private, and both within and without the construction industry — who have reached collective bargaining agreements with organized trades or occupations.12

In this case the commissioner improperly combined one element of the third proviso of c. 149, § 26, — “organized labor” — with one element of the fourth proviso — “private employers engaged in the construction industry” — to create a hybrid standard for wage rates that § 26 does not contemplate. The commissioner erred by looking to the fourth proviso, and, even if it were applicable, by not considering nonunionized workers.

The interpretation we adopt leads to no harmful or anomalous result. The wage rates of housing authority maintenance workers are still linked to rates paid unionized workers, if there are any in their locality, thus helping to ensure that they receive a reasonable wage. The commissioner must also consider wages paid to laborers by the municipality in which the workers are employed and, if the circumstances of the third proviso *57apply, by public and private employers outside the construction industry. The commissioner is then authorized to fix a wage rate not less than eighty per cent of the prevailing wage so determined. Some showing of comparability of jobs is implied in the statute. See Commissioner of Labor & Indus. v. Boston Hous. Auth., 345 Mass. 406, 417 (1963). See also Commissioner of Labor & Indus. v. Worcester Hous. Auth., 8 Mass. App. Ct. 303, 309 (1979). The commissioner may, in his sound discretion, set wage rates higher than eighty per cent to reflect genuine differences in the employment environment, such as the skills required, the hazards, and the responsibilities. He must, of course, consider fringe benefits in comparing prevailing wages.

The commissioner contends that we should defer to his interpretation of the statute. While judicial deference in general is certainly warranted, “[t]he duty of statutory interpretation is for the courts.” Utility Workers Local 466 v. Labor Relations Comm’n, 389 Mass. 500, 504 (1983), quoting Cleary v. Cardullo’s, Inc., 347 Mass. 337, 344 (1964). “In no event . . . will an administrative interpretation be followed if it is contrary to ‘plain and unambiguous terms [in] a statute.’” Saccone v. State Ethics Comm’n, 395 Mass. 326, 335 n. 12 (1985), quoting School Comm. of Springfield v. Board of Educ., 362 Mass. 417, 441 n.22 (1972). We conclude, therefore, that all housing authority wage rates based on a “prevailing wage” in the construction industry must be remanded to the commissioner for redetermination consistent with this opinion.

2. In order to decide whether summary judgment for the commissioner was warranted as to positions for which there were no analogues in the construction industry, we must decide what standard of review should be applied when a housing authority challenges the rates determined by the commissioner. The motion judge applied the rational basis test applicable to the determination of the validity of a regulation (see, e.g., Borden, Inc. v. Commissioner of Pub. Health, 388 Mass. 707, 736, cert, denied sub nom. Formaldehyde Inst., Inc. v. Frechette, 464 U.S. 936 [1983]), and upheld the redetermined rates. Certainly the rates are not regulations *58as defined in § 1 of the State Administrative Procedure Act (G. L. c. 30A) because such a rate determination is not of “general application” (G. L. c. 30A, § 1 [5]). Associated Indus. v. Commissioner of Ins., 356 Mass. 279, 284 (1969). Nor is there a basis for treating the process as an adjudicatory proceeding under G. L. c. 30A. The Legislature has declared the process not to be an adjudicatory proceeding (G. L. c. 30A, §![!][/]» inserted by St. 1966, c. 497, referring to the predecessor of G. L. c. 121B, § 29) and, in any event, there is no statutory provision for a public hearing and no constitutional right to a public hearing in favor of a housing authority. Spence v. Boston Edison Co., 390 Mass. 604, 607-610 (1983). See Trustees of Worcester State Hosp. v. The Governor, 395 Mass. 377, 380 (1985).

We have no doubt that a housing authority properly may challenge the commissioner’s rate determination as being based on an error of law. That is what the housing authorities have done successfully in the first of these consolidated cases. Beyond errors of law, a housing authority should have the right to challenge the factual basis of a rate determination as being arbitrary or capricious, that is, as lacking a rational basis. See Assessors of Sandwich v. Commissioner of Revenue, 393 Mass. 580, 588 (1984); Greenleaf Fin. Co. v. Small Loans Regulatory Bd., 377 Mass. 282,293 (1979). Unlike a challenge to a regulation in which the court attributes any supporting rational basis for the regulation to the regulation’s author (see Arthur D. Little, Inc. v. Commissioner of Health & Hosps. of Cambridge, 395 Mass. 535, 553-554 [1985]), a challenge to a statutorily mandated determination of minimum rates cannot be rejected simply by imagining circumstances that would be supporting. The method by which the agency arrived at the rates must have had a rational foundation. The commissioner’s supporting data and his calculations and conclusions should not be upheld if they are illogical or irrational. The commissioner need not have followed the best possible course in collecting information and in arriving at the rates, but the resulting rates must be logical in relation to the statutory standard. Here, to succeeed, the housing authorities must ultimately demon*59strate that what the commissioner did in establishing the rates was not rational.

We reject the housing authorities’ contention that the appropriate standard for judicial review of the commissioner’s rates is the substantial evidence test. In this Commonwealth, the substantial evidence test involves a court’s assessment of a record developed in a trial-type agency hearing. See New Boston Garden Corp. v. Assessors of Boston, 383 Mass. 456, 466-467 (1981).13 Any attempt to apply a substantial evidence test to a trial court record established after the commissioner has made his decision would overlook the deference courts should give to agency fact-finding and decision-making. The substantial evidence test has no meaning when one attempts to apply it to a record made in court rather than before an agency. A court may choose to impose a higher standard of review than the rational basis test. A court may require that any agency record of some sort be made and that the agency explain its decision. A court may even require a trial-type hearing be held in particular circumstances, even if no statute so prescribes. See Massachusetts Medical Serv. v. Commissioner of Ins., 344 Mass. 335, 339 (1962). It is not feasible, however, to apply the traditional substantial evidence test, with appropriate deference to fact-finding of the administrative agency, to a factual record made in court.14

*603. We turn then to the question whether the summary judgment material before the motion judge presented a dispute of material fact concerning the existence of a rational or logical basis for the rates the commissioner established for positions not found in the construction industry. We conclude that the BHA raised sufficient doubt as to the rationality of the commissioner’s method for setting wages as to bar summary judgment for the commissioner.15

In the comparability study the commissioner conducted following the remand order in the first case, he recognized that certain housing authority positions had no comparable counterparts in the construction industry, and, thus, he undertook to find nonconstruction industry collective bargaining agreements that could serve as bases for his wage determinations for these positions. Such an approach was consistent with his statutory duties. The housing authorities contend, however, that the commissioner’s method for determining comparability was so deficient as to be irrational. They rely on an affidavit of an expert on job comparability that challenges the design, execution, and conclusions of the commissioner’s study.

*61A finding of reasonable comparability is essential if the commissioner is to base a housing authority wage rate on a particular trade’s or occupation’s prevailing wage. We have already held that the third proviso of G. L. c. 149, § 26, requires that the commissioner investigate bargaining agreements both inside and outside the construction industry, and that he may at times be forced to look only at nonconstruction industry analogues. “The statutory concepts of ‘prevailing wage’ and the ‘wage rate . . . established in certain trades and occupations’ only have meaning in the context of evaluating similar jobs. Implicit in both statutes is the requirement that the Commissioner make careful job comparisons.” Commissioner of Labor & Indus. v. Worcester Hous. Auth., 8 Mass. App. Ct. 303, 309 (1979). See Commissioner of Labor & Indus. v. Boston Hous. Auth., 345 Mass. 406, 417 (1963).

The commissioner argues that, even if comparability is required, his study establishes at least a rational foundation for concluding that the five positions still at issue are reasonably comparable to similarly titled trades and occupations outside the construction industry. The commissioner’s survey instruments were derived from definitions contained in the Federal Dictionary of Occupational Titles (D.O.T.), and asked, in substance, whether each housing authority employee with a particular title performed the tasks set out in the D.O.T. definition. The commissioner concedes that this methodology may have emphasized similarities with similarly-titled trades, but he contends that an expanded, broader-based study would be “merely a sociological survey of work performed.” The commissioner argues that the housing authorities’ assertion of a dispute of material fact collapses simply to a difference of opinion on the proper scope of such a comparability study.

The housing authorities respond with criticisms of all facets of the comparability study. Three of their complaints seem of particular significance in the context of housing authority positions with no construction industry analogues. In the first place, the authorities argue that the study is irrationally biased in favor of finding comparability. They note that the formal part of the survey instrument catalogues only the ways in which a *62housing authority position mimicked a particular trade; only a blank page, the responses from which were not collated, catalogued the ways in which a housing authority position and the trade in question differed. Since the questions on the formal survey instrument were always derived from the definition of the trade itself, the commissioner could scarcely fail to discover that, at least in some respects, overlap existed between the housing authority position and the similarly titled trade. Thus, the authorities argue, the commissioner’s finding of comparability is meaningless.

Second, the authorities argue that, on two of the central concerns of the study — hazards and fringe benefits — the commissioner’s methodology was explicitly biased. The commissioner openly stated that “[t]he purpose of th[e hazards] section [of the study] was to establish that a comparable level of hazard existed between the . . . trade and housing authority work” (emphasis supplied). The authorities contend that the commissioner asserted without any support that the vast array of employer-paid fringe benefits afforded housing authority personnel (but, ordinarily, not tradesmen) were approximately balanced by the twenty per cent differential between the prevailing wage and the wage rates set under G. L. c. 121B, § 29.

Finally, and perhaps most significantly, the authorities note that, even if the commissioner established comparability between a certain housing authority position and the abstract definition of a particular “trade” found in the D.O.T., the commissioner has not established — and the study does not purport to establish — comparability between the D.O.T. definition and the real-world trade from which the prevailing wage is derived. Without this latter comparison, the authorities argue, nothing can be said about the comparability of a housing authority position and a real-world trade or occupation.

In our opinion, these challenges raise genuine issues of fact about the rationality of the commissioner’s study. On the basis of the record before us, we cannot say that the rates established have an unquestionably rational basis.

4. We affirm the judgment of the Superior Court in the first case. We reverse the summary judgment for the commissioner *63in the second case, and remand that case for further proceedings consistent with this opinion.

So ordered.

(concurring). I applaud the court’s conclusion that “[u]nlike a challenge to a regulation in which the court attributes any supporting rational basis for the regulation to the regulation’s author, (see Arthur D. Little, Inc. v. Commissioner of Health & Hosps. of Cambridge, 395 Mass. 535, 553-554 [1985]), a challenge to a statutorily mandated determination of minimum rates cannot be rejected simply by imagining circumstances that would be supporting,” and that “{t]he commissioner’s . . . calculations and conclusions should not be upheld if they are illogical or irrational.” Ante at 58. I would, however, subject the commissioner’s action to the test of reasonableness rather than rationality. This court and the parties agree that the wage rates are, strictly speaking, neither a regulation nor an adjudication. When an administrative action is neither an adjudication nor the promulgation of a regulation but consists of rate setting, “our task is to determine ‘whether the commissioner has complied with the standards prescribed by the statute,’ although ‘we are not thereby authorized to substitute our judgment as to the reasonableness or adequacy of the [rates] for that of the commissioner. ’ ” Westland Hous. Corp. v. Commissioner of Ins., 352 Mass. 374, 384-385 (1967), quoting Massachusetts Bonding & Ins. Co. v. Commissioner of Ins., 329 Mass. 265, 273 (1952). In other rate setting contexts we determine whether the rates have reasonable support in the evidence, Westland Hous. Corp., supra at 385. I would, therefore, hold that the BHA may attempt to show that the wage rates established by the commissioner have no reasonable support. In applying this standard, I would be mindful of the deference due the commissioner’s specialized knowledge, technical competence, and experience regarding issues within the scope of his statutorily delegated authority. Workers’ Com*64pensation Rating & Inspection Bureau v. Commissioner of Ins., 391 Mass. 238, 246 (1984).

I am unsure if the reasonable support test I advocate would in this case compel a result any different from that adopted by the court. A test phrased in terms of reasonableness, however, would distinguish it from the traditional rational basis test which has been rejected in this case by the court and which I would abandon completely in the review of administrative decisions. See Arthur D. Little, Inc. v. Commissioner of Health & Hosps. of Cambridge, 395 Mass. 535, 557-563 (1985) (Lynch, L, dissenting). Although I see no real difference between the concepts of rational basis as the court now defines it, and reasonable support, reasonable support, unlike rational basis, is a term that has resulted in meaningful judicial review in other cases. I would reject any suggestion that the concept of rationality, as opposed to reasonableness, results in any greater deference to the administrative determination being considered. Since we have recently attempted to eliminate confusion by pointing out that there is no essential difference between a duty to look for reasonable support in the evidence and a duty to look for substantial evidence in the record, ante at note 13, the reasonable support test would, I believe, further that desirable purpose. The reasonable support test I suggest requires a familiar mode of judicial review. Any such test requires an examination of the basis for the administrative determination. I would follow the suggestion of the court, that a reviewing court may require that a record be made by the agency and that it explain its decision, or that a trial-type hearing be held in appropriate circumstances. Ante at 59. I would not eliminate the possibility, however, as the court has done, that some circumstances might exist that would make it appropriate for a court to develop the record upon which an administrative action is based. If, as in this case, there is no procedure mandated by statute for the development of a record justifying the rates, and if a reviewing court should be satisfied that the agency charged with the responsibility has either failed or refuses to develop such a record, it seems to me appropriate for the Superior Court to do so.